Impact of dairy products and dietary calcium on bone-mineral content in children: results of a meta-analysis

Production, Composition and Nutritional Properties of Organic Milk: A Critical Review

Milk is one of the most valuable products in the food industry with most milk production throughout the world being carried out using conventional management, which includes intensive and traditional systems. The intensive use of fertilizers, antibiotics, pesticides and concerns regarding animal health and the environment have given increasing importance to organic dairy and dairy products in the last two decades. This review aims to compare the production, nutritional, and compositional properties of milk produced by conventional and organic dairy management systems. We also shed light on the health benefits of milk and the worldwide scenario of the organic dairy production system. Most reports suggest milk has beneficial health effects with very few, if any, adverse effects reported. Organic milk is reported to confer additional benefits due to its lower omega-6-omega-3 ratio, which is due to the difference in feeding practices, with organic cows predominantly pasture fed. Despite the testified animal, host, and environmental benefits, organic milk production is difficult in several regions due to the cost-intensive process and geographical conditions. Finally, we offer perspectives for a better future and highlight knowledge gaps in the organic dairy management system.

Dairy product consumption, eating habits, sedentary behaviour and physical activity association with bone mineral density among adolescent boys: a cross-sectional observational study

BACKGROUND

During childhood and adolescence, skeletal microarchitecture and bone mineral density (BMD) undergo significant changes. Peak bone mass is built and its level significantly affects the condition of bones in later years of life. Understanding the modifiable factors that improve bone parameters at an early age is necessary to early prevent osteoporosis. To identify these modifiable factors we analysed the relationship between dairy product consumption, eating habits, sedentary behaviour, and level of physical activity with BMD in 115 young boys (14-17 years).

METHODS

Bone parameters were measured by dual energy x-ray absorptiometry using paediatric specific software to compile the data. Dairy product consumption and eating habits were assessed by means of a dietary interview. Sedentary behaviour and physical activity was assessed in a face-to-face interview conducted using the International Physical Activity Questionnaire. Data collection on total physical activity level was performed by collecting information on the number of days and the duration of vigorous and moderate intensity (MVPA) and average daily time spent in sitting (SIT time).

RESULTS

The strongest relationships with BMD in distal part of forearm were found for moderate plus vigorous activity, sit time, and intake of dairy products, intake of calcium, protein, vitamin D, phosphorus from diet. Relationships between BMD, bone mineral content (BMC) in the distal and proximal part of the forearm and PA, sit time and eating parameters were evaluated using the multiple forward stepwise regression. The presented model explained 48-67% (adjusted R2 = 0.48-0.67; p < 0.001) of the variance in bone parameters. The predictor of interactions of three variables: protein intake (g/person/day), vitamin D intake (µg/day) and phosphorus intake (mg/day) was significant for BMD dis (adjusted R2 = 0.59; p < 0.001). The predictor of interactions of two variables: SIT time (h/day) and dairy products (n/day) was significant for BMD prox (adjusted R2 = 0.48; p < 0.001). Furthermore, the predictor of interactions dairy products (n/day), protein intake (g/person/day) and phosphorus intake (mg/day) was significant for BMC prox and dis (adjusted R2 = 0.63-0.67; p < 0.001).

CONCLUSIONS

High physical activity and optimal eating habits especially adequate intake of important dietary components for bone health such as calcium, protein, vitamin D and phosphorus affect the mineralization of forearm bones.

Calcium - a scoping review for Nordic Nutrition Recommendations 2023

The aim of this scoping review was to conduct evidence-based documentations between calcium (Ca) intake and health outcomes for updating dietary reference values (DRVs) and food-based dietary guidelines (FBDGs) in the sixth edition of Nordic Nutrient Recommendations (NNR2023). The systematic literature search was limited to reviews on human data published between 2011 and June 2021. Systematic reviews (SRs) and original publications of relevance for this scoping review were included. A common practice of designing studies on health outcomes related to Ca supplement intake is to examine combined Ca and vitamin D, and therefore, a combination of Ca with vitamin D (CaD) was included in this review. In total, 27 studies addressing the association between dietary or supplemental Ca on bone health, bone mineral density (BMD), pregnancy-related outcomes, cardiovascular diseases (CVD), cancers, obesity, and mortality were reviewed. SRs showed that both dietary and supplemental Ca intakes were positively associated with BMD, but evidence did not support the benefit in fracture prevention. Current evidence did not support that Ca or CaD supplementation increases risk of coronary heart disease or all-cause mortality in older adults, but that Ca may be beneficial for hypertension, especially in young people. Increasing Ca intake may be beneficial during pregnancy, especially for those at high risk of pre-eclampsia due to ethnicity, age, high BMI, and those with low baseline Ca intake. The associations between high Ca intake and cancers were varied, with strong evidence that high consumption of dairy products is protective against colorectal cancer and limited-suggestive evidence that dairy products and diets high in Ca might also be protective against breast cancer. Moreover, there is limited-suggestive evidence that dairy products and diets high in Ca increase the risk of prostate cancer. Based on current evidence, Ca intake is beneficial or neutral in relation to most of the outcomes evaluated in this review. Data from the Nordic countries show that average Ca intake is around the same as previously recommended by NNR. However, the average Ca intake in the Baltic countries is below the recommendations.

Musculoskeletal health in children and adolescents

The purpose of this narrative review was to investigate the key determinants of musculoskeletal health in childhood and adolescence, with particular attention to the role of physical activity. First, we examined the importance of bone modeling and remodeling in maintaining the bone health and the integrity and mechanical characteristic of the skeleton. In addition, we reported the evidence on an appropriate calcium and vitamin D intake, as well as local load variation in achieving proper peak bone mass. Proteomic and transcriptomic studies identified the skeletal muscle "secretoma", consisting of several myokines involved in endocrine and paracrine functions. Among these, we explored the role of irisin, a myokine involved in the muscle-bone crosstalk, and in the regulation of metabolic pathways. It is known that physical activity during growing positively impacts on skeleton and can protect by bone loss in adulthood. However, there are still concerns about the optimal interval duration and exercise intensity, particularly at the pubertal growth spurt which represents a window of opportunity to increase skeletal strength. We reported data from clinical trials performed in the last 5 years analyzing the impact of the type and timing of physical activity during childhood on skeletal development. Finally, we reported recent data on the significance of physical activity in some rare diseases.

The Impact of Whole Egg Consumption on Bone Accrual in Healthy Children: A Randomized Controlled Trial

Dietary interventions designed to examine the role of nutrition on childhood bone accrual have often focused on the role of individual micronutrients (eg, calcium, vitamin D, and zinc) and macronutrients (eg, protein). The osteogenic benefits of whole foods, such as eggs, are not well understood despite eggs being a source of high-quality nutrients and bioactive compounds known to positively influence bone. A significant positive cross-sectional association between whole egg consumption and tibia cortical bone mass has recently been shown in young children; however, randomized controlled trials (RCTs) have not been conducted. This study is a double-blind RCT in male and female children ages 9-13 years of different ancestries, designed to determine if consuming food products with whole eggs (equivalent to 8-10 eggs/wk) versus foods with milk or gelatin (placebo) over a 9-month period will improve measures of bone strength. Total body less head (TBLH) and lumbar spine bone mineral content (BMC) and areal bone mineral density (aBMD) were assessed using dual-energy X-ray absorptiometry (DXA). DXA Z-scores were computed using published pediatric growth charts and were adjusted for height-for-age Z-score (HAZ). Mid-tibia cortical volumetric BMD, BMC, cortical area, total bone area, cortical thickness, and strength strain index were measured using peripheral quantitative computed tomography. Overall, there were no significant intervention effects for any bone outcomes. The increase in spine BMCHAZ Z-score in the egg group versus the gelatin group approached significance (p = 0.07). Significant time effects in TBLH aBMDHAZ Z-score occurred as all groups decreased over 9 months (p < 0.03). Most tibia cortical bone outcomes increased over time (all p < 0.02), but changes did not differ across intervention groups. Whole eggs provide important nutritional benefits for children, but the bone responses to consumption of 8-10 eggs/wk over a period of 9 months in children entering the early stages of puberty were small. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Types of dairy foods and risk of fragility fracture in the prospective Nurses' Health Study cohort

BACKGROUND

Fragility fractures present enormous health challenges for women. Dairy products provide many bone-beneficial nutrients, such as calcium and vitamin D. Individual dairy foods may exert different effects on bone health.

OBJECTIVES

The aim of this study was to investigate the associations between total dairy, yogurt, milk, and cheese and fragility fracture risk among females in the prospective Nurses' Health Study (NHS) conducted in the United States.

METHODS

In the current analysis, 103,003 females with mean age of 48 y were followed from 1980-2004. Proportional hazards models were used to estimate risk of first fracture (of the wrist, hip, or vertebrae) by intakes of dairy foods (total dairy, milk, yogurt, or cheese) obtained from a food frequency questionnaire. Fractures that were caused by high-trauma events were not included. We relied on self-reported data for wrist and hip fractures whereas for vertebral fractures, medical records were used to confirm cases.

RESULTS

A total of 5495 incident fracture cases were documented during follow-up. After controlling for relevant confounding variables, consumption of ≥2 servings/d of total dairy (compared with <1 serving/d) was associated with lower fracture risk (hazard ratio [HR]: 0.74; 95% confidence interval [CI]: 0.61, 0.89). More than 2 servings of milk per day (compared with <1 serving/d) were associated with a lower fracture risk (HR: 0.85; 95% CI: 0.77, 0.94). Intakes of calcium, vitamin D, and protein from nondairy sources did not modify the effects of total dairy or milk on fracture risk. There was no association between yogurt intake and fracture risk. Intake of cheese (≥1 servings/d compared with <1 serving/wk) was weakly associated with lower fracture risk (HR: 0.89; 95% CI: 0.79, 0.99).

CONCLUSIONS

Higher total dairy, milk, and cheese intakes are associated with lower risks of fracture in females in the NHS.

Determinants of bone parameters in young paediatric cancer survivors: the iBoneFIT project

BACKGROUND

Bone health is remarkably affected by endocrine side effects due to paediatric cancer treatments and the disease itself. We aimed to provide novel insights into the contribution of independent predictors of bone health in young paediatric cancer survivors.

METHODS

This cross-sectional multicentre study was carried out within the iBoneFIT framework in which 116 young paediatric cancer survivors (12.1 ± 3.3 years old; 43% female) were recruited. The independent predictors were sex, years from peak height velocity (PHV), time from treatment completion, radiotherapy exposure, region-specific lean and fat mass, musculoskeletal fitness, moderate-vigorous physical activity and past bone-specific physical activity.

RESULTS

Region-specific lean mass was the strongest significant predictor of most areal bone mineral density (aBMD), all hip geometry parameters and Trabecular Bone Score (β = 0.400-0.775, p ≤ 0.05). Years from PHV was positively associated with total body less head, legs and arms aBMD, and time from treatment completion was also positively associated with total hip and femoral neck aBMD parameters and narrow neck cross-sectional area (β = 0.327-0.398, p ≤ 0.05; β = 0.135-0.221, p ≤ 0.05), respectively.

CONCLUSION

Region-specific lean mass was consistently the most important positive determinant of all bone parameters, except for total hip aBMD, all Hip Structural Analysis parameters and Trabecular Bone Score.

IMPACT

The findings of this study indicate that region-specific lean mass is consistently the most important positive determinant of bone health in young paediatric cancer survivors. Randomised clinical trials focused on improving bone parameters of this population should target at region-specific lean mass due to the site-specific adaptations of the skeleton to external loading following paediatric cancer treatment. After paediatric cancer diagnosis, years from peak height velocity (somatic maturity) is critical for bone development.

The Effects of Dairy Product Supplementation on Bone Health Indices in Children Aged 3 to 18 Years: A Meta-Analysis of Randomized Controlled Trials

Childhood and adolescence are critical periods for optimizing skeletal growth. Dairy products are valuable sources of bone-beneficial nutrients, particularly calcium and protein. A random-effects meta-analysis of published randomized controlled trials was performed to quantitatively assess the effects of dairy supplementation on bone health indices in children and adolescents. The PubMed and Web of Science databases were searched. Dairy supplementation increased whole-body bone mineral content (BMC) (+25.37 g) and areal bone mineral density (aBMD) (+0.016 g/cm2), total hip BMC (+0.49 g) and aBMD (+0.013 g/cm2), femoral neck BMC (+0.06 g) and aBMD (+0.030 g/cm2), lumbar spine BMC (+0.85 g) and aBMD (+0.019 g/cm2), and height (0.21 cm). When expressed as a percentage difference, whole-body BMC was increased by 3.0%, total hip BMC by 3.3%, femoral neck BMC by 4.0%, lumbar spine BMC by 4.1%, whole-body aBMD by 1.8%, total hip aBMD by 1.2%, femoral neck aBMD by 1.5%, and lumbar spine aBMD by 2.6%. Dairy supplementation increased serum insulin-like growth factor I concentrations (19.89 nmol/L) and reduced concentrations of urinary deoxypyridinoline (-1.78 nmol/mmol creatinine) and serum parathyroid hormone (-10.46 pg/mL) but did not significantly affect the serum concentrations of osteocalcin, bone alkaline phosphatase, and C-terminal telopeptide of type 1 collagen. Serum 25-hydroxyvitamin D concentrations (+4.98 ng/mL) increased with vitamin D-fortified dairy supplementation. The positive effects on bone mineral mass parameters and height were generally consistent across subgroups defined by sex, geographical region, baseline calcium intake, calcium from the supplementation, trial duration, and Tanner stages. In summary, dairy supplementation during growth leads to a small but significant increase in bone mineral mass parameters, and these findings are generally supported by the changes in several biochemical parameters related to bone health.

Formula Milk Supplementation and Bone Acquisition in 4-6 Years Chinese Children: A 12-Month Cluster-Randomized Controlled Trial

Dairy foods are crucial for adequate calcium intake in young children, but scarce data are available on the effects of formula milk on bone acquisition. This cluster-randomized controlled trial investigated the effects of the supplementation of formula milk on bone health in rural children accustomed to a low-calcium diet between September 2021 and September 2022. We recruited 196 healthy children aged 4-6 years from two kindergartens in Huining County, Northwest China. A class-based randomization was used to assign them to receive 60 g of formula milk powder containing 720 mg calcium and 4.5 µg vitamin D or 20-30 g of bread per day for 12 months, respectively. Bone mineral density (BMD) and bone mineral content (BMC) at the left forearm and calcaneus, bone biomarkers, bone-related hormones/growth factors, and body measures were determined at baseline, 6, and 12 months. A total of 174 children completed the trial and were included in the analysis. Compared with the control group, formula milk intervention showed significant extra increments in BMD (3.77% and 6.66%) and BMC (4.55% and 5.76%) at the left forearm at 6th and 12th months post-intervention (all p < 0.001), respectively. Similar trends were observed in BMD (2.83%) and BMC (2.38%) in the left calcaneus at 6 months (p < 0.05). The milk intervention (vs. control) also showed significant changes in the serum concentrations of osteocalcin level (-7.59%, p = 0.012), 25-hydroxy-vitamin-D (+5.54%, p = 0.001), parathyroid hormone concentration (-15.22%, p = 0.003), and insulin-like growth factor 1 (+8.36%, p = 0.014). The percentage increases in height were 0.34%, 0.45%, and 0.42% higher in the milk group than in the control group after 3-, 6-, and 9-month intervention, respectively (p < 0.05). In summary, formula milk supplementation enhances bone acquisition at the left forearm in young Chinese children.

Effect of soluble corn fibre and calcium supplementation on bone mineral content and bone mineral density in preadolescent Malaysian children-a double-blind randomised controlled trial (PREBONE-Kids Study)

Soluble corn fibre (SCF) with calcium did not improve bone indices after 1 year in preadolescent children.

INTRODUCTION

SCF has been reported to improve calcium absorption. We investigated the long-term effect of SCF and calcium on bone indices of healthy preadolescent children aged 9-11 years old.

METHODS

In a double-blind, randomised, parallel arm study, 243 participants were randomised into four groups: placebo, 12-g SCF, 600-mg calcium lactate gluconate (Ca) and 12-g SCF + 600-mg calcium lactate gluconate (SCF + Ca). Total body bone mineral content (TBBMC) and total body bone mineral density (TBBMD) were measured using dual-energy X-ray absorptiometry at baseline, 6 and 12 months.

RESULTS

At 6 months, SCF + Ca had a significant increase in TBBMC from baseline (27.14 ± 6.10 g, p = 0.001). At 12 months, there was a significant increase in TBBMC from baseline in the SCF + Ca (40.28 ± 9.03 g, p = 0.001) and SCF groups (27.34 ± 7.93 g, p = 0.037). At 6 months, the change in TBBMD in the SCF + Ca (0.019 ± 0.003 g/cm²) and Ca (0.014 ± 0.003 g/cm²) groups was significantly different (p < 0.05) from SCF (0.004 ± 0.002 g/cm²) and placebo (0.002 ± 0.003 g/cm²). However, the changes in TBBMD and TBBMC were not significantly different among groups at 12 months.

CONCLUSION

SCF did not increase TBBMC and TBBMD in Malaysian children after 1 year although calcium supplementation increased TBBMD at 6 months. Further work is needed to fully understand the mechanism and health benefits of prebiotics in this study population.

CLINICAL TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT03864172.

Effect of Circadian Rhythm Disturbance on the Human Musculoskeletal System and the Importance of Nutritional Strategies

The circadian system in the human body responds to daily environmental changes to optimise behaviour according to the biological clock and also influences various physiological processes. The suprachiasmatic nuclei are located in the anterior hypothalamus of the brain, and they synchronise to the 24 h light/dark cycle. Human physiological functions are highly dependent on the regulation of the internal circadian clock. Skeletal muscles comprise the largest collection of peripheral clocks in the human body. Both central and peripheral clocks regulate the interaction between the musculoskeletal system and energy metabolism. The skeletal muscle circadian clock plays a vital role in lipid and glucose metabolism. The pathogenesis of osteoporosis is related to an alteration in the circadian rhythm. In the present review, we discuss the disturbance of the circadian rhythm and its resultant effect on the musculoskeletal system. We also discuss the nutritional strategies that are potentially effective in maintaining the system's homeostasis. Active collaborations between nutritionists and physiologists in the field of chronobiological and chrononutrition will further clarify these interactions. This review may be necessary for successful interventions in reducing morbidity and mortality resulting from musculoskeletal disturbances.

Calcium status assessment at the population level: Candidate approaches and challenges

Inadequate dietary calcium intake is a global public health problem that disproportionately affects low- and middle-income countries. However, the calcium status of a population is challenging to measure, and there are no standard methods to identify high-risk communities even in settings with an elevated prevalence of a disease caused or exacerbated by low calcium intake (e.g., rickets). The calcium status of a population depends on numerous factors, including intake of calcium-rich foods; the bioavailability of the types of calcium consumed in foods and supplements; and population characteristics, including age, sex, vitamin D status, and genetic attributes that influence calcium retention and absorption. The aim of this narrative review was to assess candidate indicators of population-level calcium status based on a range of biomarkers and measurement methods, including dietary assessment, calcium balance studies, hormonal factors related to calcium, and health outcomes associated with low calcium status. Several promising approaches were identified, but there was insufficient evidence of the suitability of any single indicator to assess population calcium status. Further research is required to develop and validate specific indicators of calcium status that could be derived from the analysis of data or samples that are feasibly collected in population-based surveys.

The effect of calcium supplementation in people under 35 years old: A systematic review and meta-analysis of randomized controlled trials

Background:

The effect of calcium supplementation on bone mineral accretion in people under 35 years old is inconclusive. To comprehensively summarize the evidence for the effect of calcium supplementation on bone mineral accretion in young populations (≤35 years).

Methods:

This is a systematic review and meta-analysis. The Pubmed, Embase, ProQuest, CENTRAL, WHO Global Index Medicus, Clinical Trials.gov, WHO ICTRP, China National Knowledge Infrastructure (CNKI), and Wanfang Data databases were systematically searched from database inception to April 25, 2021. Randomized clinical trials assessing the effects of calcium supplementation on bone mineral density (BMD) or bone mineral content (BMC) in people under 35 years old.

Results:

This systematic review and meta-analysis identified 43 studies involving 7,382 subjects. Moderate certainty of evidence showed that calcium supplementation was associated with the accretion of BMD and BMC, especially on femoral neck (standardized mean difference [SMD] 0.627, 95% confidence interval [CI] 0.338–0.915; SMD 0.364, 95% CI 0.134–0.595; respectively) and total body (SMD 0.330, 95% CI 0.163–0.496; SMD 0.149, 95% CI 0.006–0.291), also with a slight improvement effect on lumbar spine BMC (SMD 0.163, 95% CI 0.008–0.317), no effects on total hip BMD and BMC and lumbar spine BMD were observed. Very interestingly, subgroup analyses suggested that the improvement of bone at femoral neck was more pronounced in the peripeak bone mass (PBM) population (20–35 years) than the pre-PBM population (<20 years).

Conclusions:

Our findings provided novel insights and evidence in calcium supplementation, which showed that calcium supplementation significantly improves bone mass, implying that preventive calcium supplementation before or around achieving PBM may be a shift in the window of intervention for osteoporosis.

Funding:

This work was supported by Wenzhou Medical University grant [89219029].

Osteoporosis and bone fractures are common problems among older people, particularly older women. These conditions cause disability and reduce quality of life. Progressive loss of bone mineral density is usually the culprit. So far, strategies to prevent bone weakening with age have produced disappointing results. For example, taking calcium supplements in later life only slightly reduces the risk of osteoporosis or fracture. New approaches are needed.

Bone mass increases gradually early in life and peaks and plateaus around 20-35 years of age. After that period, bone mass slowly declines. Some scientists suspect that increasing calcium intake during this period of peak bone mass may reduce osteoporosis or fracture risk later in life.

A meta-analysis by Liu, Le et al. shows that boosting calcium intake in young adulthood strengthens bones. The researchers analyzed data from 43 randomized controlled trials that enrolled 7,382 participants. About half the studies looked at the effects of taking calcium supplements and the other half analyzed the effects of a high calcium diet. Boosting calcium intake in people younger than age 35 improved bone mineral density throughout the body. It also increased bone mineral density at the femoral neck, where most hip fractures occur. Calcium supplementation produced larger effects in individuals between the ages of 20 and 35 than in people younger than 20.

Both high calcium diets and calcium supplements with doses less than 1000 mg/d boosted bone strength. Higher dose calcium supplements did not provide any extra benefits. The analysis suggests people should pay more attention to bone health during early adulthood. Large randomized clinical trials are needed to confirm the long-term benefits of boosting calcium intake during early adulthood. But if the results are validated, taking calcium supplements, or eating more calcium-rich foods between the ages of 20 and 35 may help individuals build healthier bones and prevent fractures and osteoporosis later in life.

A population based case-control study of association between dietary calcium intake and ulcerative colitis in adults

Limited data are available on the association of dietary calcium intake and ulcerative colitis (UC). We aimed to investigate the relation between dietary calcium intake and UC prevalence in Iranian adults. In this population-based case-control study, diagnosed patients with UC by gastroenterologists that were registered in the Iranian inflammatory bowel disease registry were included as cases. Age and sex-matched healthy controls were selected from Study on the Epidemiology of Psychological, Alimentary Health and Nutrition (SEPAHAN) dataset. Dietary calcium intakes of participants were examined through a validated food frequency questionnaire. We included 327 middle-aged participants (109 cases and 218 controls) in the analysis; 52.1% of them were females. After adjustments for potential confounders, individuals in the third tertile of dietary calcium intake had 92% lower odds of UC, compared to those in the first tertile (OR = 0.08, 95% CI 0.02-0.27). Our analysis based on recommended dietary allowances (RDAs) intake showed that dietary Ca intake deficiency was related to increased odds of UC (OR = 9.5, 95% CI 2.98-30.91). Stratified analysis by gender revealed that these associations were significant in both genders; although the results were stronger in the male population. A Significant decreasing trend was observed for odds of UC in tertiles of dietary calcium intakes, in both males and females. Higher dietary calcium intake was associated with lower UC prevalence in Iranian adults. Inadequate dietary calcium intake was also linked to elevated odds of UC. Further prospective investigations are needed to affirm these findings.

Lactose Malabsorption and Presumed Related Disorders: A Review of Current Evidence

Background. Lactose malabsorption (LM) is a frequent clinical problem associated with several digestive and extra-digestive diseases. The aim of this manuscript was to clarify the real clinical impact of LM on these disorders. Methods. A literature search for digestive and extra-digestive disorders related to LM was carried out using PubMed, Medline and Cochrane. Results. A transient lactase deficiency is present in celiac disease (CD) on a normal diet. The persistence of symptoms in CD on a gluten-free diet may be instead, in part, attributed to a primary LM. Similar circumstances are present in inflammatory bowel diseases (IBD), in which LM can be responsible for a part of persistent symptoms in IBD on clinical remission. LM and irritable bowel syndrome (IBS) are instead independent conditions. On the other hand, a lactose-restricted diet may be useful for some IBS patients. A reduced lactose intake can lead to low bone mass and limited risk of fragility fractures. Finally, the absorption of levothyroxine could be conditioned by LM. Conclusions. LM can be responsible for persistent symptoms in CD and IBD. The association with IBS seems to be casual. Bone mass and levothyroxine absorption can be affected by LM.

Prevalence of lactose intolerance and malabsorption among children of two ethnic groups from the urban areas of Malaysia and its relation to calcium intake and bone health status

Lactase insufficiency could develop into lactose intolerance (LI) and disrupt the intake of calcium, which is a core nutrient for bone development in children. However, data regarding the prevalence of LI and bone health status (BHS) among Malaysian children are scarcely reported.

PURPOSE

This study aimed to determine the prevalence of LI and lactose malabsorption (LM) in Malay and Chinese children and examine its relationship with calcium intake (CI) and BHS.

METHODS

A total of 400 children participated in this study. The prevalence of lactose tolerance (LT) was assessed using hydrogen breath test, LT test, and visual analogue scales. Assessment of CI was performed using a 24-h dietary recall interview (24-h DR) and food frequency questionnaire (FFQ). Calcaneal broadband ultrasound attenuation (BUA) was measured using a quantitative ultrasonometer.

RESULTS

The prevalence of LI among Chinese children (37%) was significantly higher (p = 0.002) than among Malay children (22.5%). However, 61.5% of Malay and 54.5% of Chinese children were found to have LM. CI of the children fulfilled 30.5% and 33.9% of the Malaysian recommended CI (1300 mg/day) for 24-h DR and FFQ, respectively. The BUA score of Malay children was significantly higher (p < 0.001) than that of Chinese children. However, LT and CI were not correlated with BHS (p > 0.05, respectively).

CONCLUSIONS

LI was diagnosed among Malay and Chinese children. However, the higher prevalence of LM is rather worrying as it could develop to LI. The prevalence possibly has been worsened by insufficient CI. Thus, effective approaches to increase CI are highly needed as bone development occurs rapidly at this age and is important for the attainment of the optimum peak bone mass during late adolescence.

Nutrition in Patients with Lactose Malabsorption, Celiac Disease, and Related Disorders

Lactose malabsorption (LM), celiac disease (CD), non-celiac gluten sensitivity (NCGS), and irritable bowel syndrome (IBS) are conditions associated with food triggers, improvement after withdrawal, treatment with dietary restriction, and subsequent nutritional detriments. LM occurs when there is incomplete hydrolysis of lactose due to lactase deficiency and frequently produces abdominal symptoms; therefore, it can cause lactose intolerance (LI). A lactose-restricted diet is frequently recommended, although it can potentially lead to nutrient deficiencies. Furthermore, lactose is an essential component of fermentable oligo-, di-, and monosaccharides and polyols (FODMAPs) and is subsequently associated with intolerance to these compounds, especially in IBS. LM commonly presents in CD. Nutritional deficits are common in CD and can continue even on a gluten-free diet (GFD). Conditions triggered by gluten are known as gluten-related disorders (GRDs), including CD, wheat allergy, and NCGS. IBS can also be associated with a gluten sensitivity. A GFD is the treatment for CD, GRDs, and gluten sensitive IBS, although compliance with this restricted diet can be difficult. Strict dietary therapies can have a negative effect on quality of life. This review aims to provide an overview of the difficult nutritional elements of these disorders, which are critical for medical providers to recognize when managing these patients.

The Effects of Milk Supplementation on Bone Health Indices in Adults: A Meta-Analysis of Randomized Controlled Trials

Milk contains a number of bone-beneficial nutrients. However, milk, due to the D-galactose content, might have unfavorable effects on bone health. A meta-analysis of randomized controlled trials (RCTs) was performed to clarify the effects of milk supplementation on bone mineral density (BMD), bone turnover markers [N-terminal telopeptide of type I collagen (NTx), C-terminal telopeptide of type 1 collagen (CTx), osteocalcin, bone alkaline phosphatase (BALP), and procollagen type 1 N-propeptide (P1NP)], and hormonal indices related to bone metabolism [parathyroid hormone (PTH), 25-hydroxyvitamin D [25(OH)D], and insulin-like growth factor 1 (IGF-1)] in adults. The PubMed and Web of Science databases were searched. A random-effects model was used to estimate the pooled effect sizes. A total of 20 RCTs were included. The trial duration ranged from 1 mo to 36 mo. Milk supplementation resulted in a small but significant increase in BMD at the hip (+0.004 g/cm2; n = 9 RCTs) and lumbar spine (+0.025 g/cm2; n = 7), but did not significantly affect whole-body BMD (n = 3) and femoral neck BMD (n = 7). Milk supplementation reduced the concentrations of P1NP (-5.20 ng/mL; n = 9), CTx (-0.16 ng/mL; n = 9), and NTx (-8.66 nmol bone collagen equivalents/mmol creatinine; n = 3). The concentrations of osteocalcin (n = 9) and BALP (n = 3) were not affected by milk supplementation. Reduced parathyroid hormone PTH (-1.01 pg/mL; n = 13) concentrations and increased IGF-1 (+1.79 nmol/l; n = 4) concentrations were observed with milk supplementation. 25(OH)D (+3.73 ng/mL; n = 11) concentrations were increased with vitamin-D fortified milk supplementation. The addition of milk to the diet may potentially increase the likelihood of preventing bone loss by restoring bone homeostasis through the modulation of the calcium-vitamin D-PTH axis, bone remodeling rate, and growth hormone/IGF-1 axis.

Circulating Levels of Bone Markers after Short-Term Intense Training with Increased Dairy Consumption in Adolescent Female Athletes

Thirteen female adolescent soccer players (14.3 ± 1.3 years) participated in a cross-over, double-blind trial examining the effects of Greek yogurt (GY) consumption on bone biomarkers during 5 days of intense soccer training. The study took place over two intervention weeks, which consisted of a pre-training assessment day, 5 training days, and a post-training assessment day. Participants completed the GY condition and a carbohydrate isocaloric placebo control pudding condition (CHO) in random order, 4 weeks apart. Morning, fasted, resting blood samples were collected pre- and post-training in each condition. Total osteocalcin (tOC), undercarboxylated osteocalcin (unOC), C-terminal telopeptide of type 1 collagen (CTX), osteoprotegerin (OPG), and receptor activator nuclear factor kappa-β ligand (RANKL) were measured in serum. The results showed no effects for time (pre- to post-training) or condition, and no interaction for tOC, CTX, OPG, RANKL, and the OPG/RANKL ratio. A time-by-condition interaction (p = 0.011) was observed in unOC, reflecting a post-training decrease in the GY, but not the CHO condition (-26% vs. -3%, respectively). However, relative unOC (% of tOC) decreased post-training (-16%), with no differences between conditions. These findings suggest that short-term high-impact intense training had no direct catabolic impact on bone metabolism, with GY adding no benefit beyond that of the isocaloric CHO control pudding.

The Impact of Diet and Physical Activity on Bone Health in Children and Adolescents

There is growing recognition of the role of diet and physical activity in modulating bone mineral density, bone mineral content, and remodeling, which in turn can impact bone health later in life. Adequate nutrient composition could influence bone health and help to maximize peak bone mass. Therefore, children's nutrition may have lifelong consequences. Also, physical activity, adequate in volume or intensity, may have positive consequences on bone mineral content and density and may preserve bone loss in adulthood. Most of the literature that exists for children, about diet and physical activity on bone health, has been translated from studies conducted in adults. Thus, there are still many unanswered questions about what type of diet and physical activity may positively influence skeletal development. This review focuses on bone requirements in terms of nutrients and physical activity in childhood and adolescence to promote bone health. It explores the contemporary scientific literature that analyzes the impact of diet together with the typology and timing of physical activity that could be more appropriate depending on whether they are children and adolescents to assure an optimal skeleton formation. A description of the role of parathyroid hormone (PTH) and gut hormones (gastric inhibitory peptide (GIP), glucagon-like peptide (GLP)-1, and GLP-2) as potential candidates in this interaction to promote bone health is also presented.

Hypocalcemia and Vitamin D Deficiency in Children with Inflammatory Bowel Diseases and Lactose Intolerance

Background: A diet restricted in dairy products can cause calcium and vitamin D deficiency and, secondarily, lead to malnutrition and low bone mass. The aim of the study was to determine the incidence hypocalcemia and vitamin D deficiency in children with inflammatory bowel diseases and lactose intolerance (LI). Material and Methods: A total of 107 patients were enrolled to the study (mean age 14.07 ± 3.58 years; 46.7% boys): 43 with Crohn’s disease (CD), 31 with ulcerative colitis (UC), and 33 with functional abdominal pain (AP-FGID). Hydrogen breath test with lactose and laboratory tests to assess the calcium-phosphate metabolism were performed in all patients. The results of densitometry were interpreted in 37 IBD patients. Results: LI was diagnosed in 23.2% patients with CD, 22.6% with UC, and 21.2% children with AP-FGID, (p = 0.9). Moreover, 9.5% patients with CD, in 21.4% with UC, and in 51.5% with AP-FGID had optimal concentration of 25(OH)D (p = 0.0002). Hypocalcemia was diagnosed in 21% of patients with CD, 16.1% with UC patients, AP-FGID patients had normal calcium levels (p = 0.02). There was no difference in concentrations of total calcium, phosphorus, and 25(OH)D between patients on low-lactose diet and normal diet (p > 0.05). BMD Z-score ≤ −1 SD was obtained by 12 CD patients (48%), and 6 with UC (50%). Conclusion: The use of a low-lactose diet in the course of lactose intolerance in children with inflammatory bowel diseases has no effect on the incidence of calcium-phosphate disorders and reduced bone mineral density.

Nutrient status and growth in vegan children

Vegan diets have risen in popularity over the past 9 years. However, few studies have examined nutrient status and the effect of a vegan diet on the growth of children. This study analysed the existing literature on the health impact and growth impact of selected nutrients in vegan children. We assessed the intake of calories and protein, as well as the nutrients iron, calcium, vitamin D, cobalamin and folate. With a small percentage of outliers, vegan children showed normal growth and were less often obese. We found limited evidence that children on a vegan diet can obtain all the examined nutrients. Furthermore, as proper planning and supplementation by caregivers is needed, it is currently unknown how often vegan children follow well-planned diets. Deficiencies in cobalamin, calcium, and vitamin D seem to be the biggest risks associated with a poorly planned vegan diet. For a more definitive assessment, data on the intake and nutrient status of omega-3 fatty acids, zinc, iodine, and selenium in vegan children are needed. Future research should account for demographic shifts in those following a vegan diet, and should discriminate between vegan sub-populations that are open or closed towards scientific approaches, towards health in general, and toward supplementation. Studies should assess the modes and dosages of supplementation and the use of fortified foods or drinks, as well as adherence to the diet itself. Plant ferritin as a source of iron and endogenous cobalamin synthesis warrants further scientific inquiry. In summary, the current literature suggests that a well-planned vegan diet using supplementation is likely to provide the recommended amounts of critical nutrients to provide for normal progression of height and weight in children, and can be beneficial in some aspects. However, data on 5 critical nutrients are still missing, hampering a more definitive conclusion.

Nutritional Adequacy and Diet Quality Are Associated with Standardized Height-for-Age among U.S. Children

Nutritional status affects linear growth and development. However, studies on the associations between nutritional status, diet quality, and age-standardized height in children are limited. The aim of this study was to assess the relationship between macro- and micronutrient intake and food consumption and height-for-age Z score (HAZ) among US children in the National Health and Nutrition Examination Survey (NHANES). This cross-sectional population-based study included 6116 US children aged 2–18 years. The usual dietary intake of nutrients and food groups was estimated by the multiple source method (MSM) using two-day food consumption data from NHANES 2007–2014. After adjusting for covariates, HAZ was positively associated with intakes of energy, protein, carbohydrate, fat, vitamins A, D, E, B6, and B12, thiamin, riboflavin, niacin, calcium, and iron. Children in the highest tertile of HAZ were less likely to consume lower than the EAR for vitamin E and calcium. Major foods consumed by children with lower HAZ were soft drinks, high-fat milk products, cakes, cookies, pastries, and pies, whereas children with higher HAZ tended to consume low-fat milk products, tea, and low-calorie fruit juice. These findings suggest that adequate nutritional intake, diet quality, and nutrient-dense food are important factors for height in children.

An Educational Intervention for Improving the Snacks and Beverages Brought to Youth Sports in the USA

OBJECTIVES

The purpose of this study was to test a small-scale intervention and its ability to decrease total sugar intake and number of calories offered at youth sports games.

METHODS

This study was a pre/post-test quasi-experimental design. A flier was developed and distributed to parents. The flier aimed to decrease the sugar-sweetened beverages and increase the nutritional quality of food brought to games. Baseline data were collected in 2018 (n = 61). The flier was distributed prior to the start of the league, once during the league, and posted online in 2019. Postintervention data were collected in the intervention group (n = 122) and a comparison group (n = 74). Nutritional information was collected through direct observation.

RESULTS

The average amount of total sugar provided per game per child was 25.5 g at baseline when snacks/beverages were provided at games. After the intervention, the average amount of total sugar provided significantly decreased (16.7 g/game/child, p < 0.001).

CONCLUSIONS

The intervention reduced total sugar offered and the number of sugar-sweetened beverages brought to games. It was low-cost and could be easily implemented by public health practitioners and/or parks and recreation administrators. Further, considerations could be made to implement policies relative to snacks and beverages at youth sports games.

Age and time trends of dairy intake among children and adolescents of the DONALD study

Purpose

To describe age and time trends in dietary intake of Total Dairy (TD) (g/1000 kcal Total Energy Intake) and types of dairy (weight percent of total dairy intake, w%TD) represented as Low Fat Dairy (LFD), High Sugar Dairy (HSD), Fermented Dairy (FD) and Liquid Dairy (LD) among children and adolescents in Germany.

Methods

Overall, 10,333 3-day dietary records kept between 1985 and 2019 by 1275 DONALD participants (3.5–18.5 years; boys: 50.8%) were analyzed using polynomial mixed-effects regression models.

Results

TD intake decreased with age (♂: linear trend p < 0.0001; ♀: linear and quadratic trend p < 0.0001), whereas FD (♀: linear, quadratic, cubic trend p ≤ 0.02) increased slightly in girls. HSD (♂: linear, quadratic, cubic trend p ≤ 0.004; ♀: linear, quadratic, cubic trend p ≤ 0.005) and LD (linear, quadratic trend p ≤ 0.0002) decreased with age. In terms of time trends, TD intake decreased in the last three decades, especially since 1995 (quadratic trend for ♂ 0.0007 and ♀ p = 0.004). LFD intake increased until 2010 and decreased thereafter (linear, quadratic, cubic trend p < 0.0001). HSD decreased until 1995, then increased until 2010 and decreased again afterwards (♂: linear, quadratic, cubic trend p ≤ 0.001; ♀: linear, quadratic, cubic trend p ≤ 0.003). While FD intake increased linear (in both ♂ and ♀: p < 0.0001), LD intake decreased (linear, quadratic trend p ≤ 0.03).

Conclusion

Our results showed changes in dairy consumption patterns among children and adolescents over the past three decades, demonstrating a decrease in TD intake with age and time, and a shift from liquid to solid dairy products with a simultaneous increase in fermented dairy products, while LFD and HSD fluctuated over time. Further evaluations will examine the health significance of these consumption patterns.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00394-021-02555-7.

Lactose Intolerance and Its Dietary Management: An Update

Milk is the most common food consumed worldwide and is also a major ingredient in the preparation of various dairy products. However, despite the high production and consumption of milk and milk-based products, there is a large percent of the world's population that suffer from allergies to milk solids and lactose intolerance. Lactose intolerance specifically means the inability of the body to breakdown the sugar to its simplest form for assimilation and it is due to the inefficiency or lack of the enzyme in the human body. The most convenient prevention method for the affected population is to avoid milk and milk-based products but this may be a cause of development of other health related issues that result from inadequate nutrient consumption. To help find an alternative to this problem, this study aims at first studying the underlying information on lactose intolerance and then studying plant-based beverages as a possible alternative to milk and milk-based products. Key teaching pointsLactose intolerance specifically means the inability of the body to breakdown the sugar to its simplest form for assimilation and it is due to the inefficiency or lack of the enzyme in the human body.Consumption of probiotics may help relieve the symptoms of lactose intolerance.Soy beverage can be an economical alternative for lactose intolerant populations and has calcium content comparable to bovine milk.Calcium absorption in fortified plant based beverages depends upon type of calcium salt used.

The Effects of Calcium, Magnesium, Phosphorus, Fluoride, and Lead on Bone Tissue

Bones are metabolically active organs. Their reconstruction is crucial for the proper functioning of the skeletal system during bone growth and remodeling, fracture healing, and maintaining calcium-phosphorus homeostasis. The bone metabolism and tissue properties are influenced by trace elements that may act either indirectly through the regulation of macromineral metabolism, or directly by affecting osteoblast and osteoclast proliferation or activity, or through becoming part of the bone mineral matrix. This study analyzes the skeletal impact of macroelements (calcium, magnesium, phosphorus), microelements (fluorine), and heavy metals (lead), and discusses the concentration of each of these elements in the various bone tissues.

The Combined Effects of Milk Intake and Physical Activity on Bone Mineral Density in Korean Adolescents

The purpose of this study was to examine the combined effects of milk intake and physical activity on bone mineral density in adolescents. This study was conducted using data from the 2009–2011 Korea National Health and Nutrition Examination Survey (KNHANES), which provided measurements of bone mineral density (BMD) in addition to basic health-related data. This study included 1061 adolescents aged 13 to 18 years (557 males and 504 females) whose data on milk intake and participation time in moderate to vigorous physical activity were available. BMD was measured by dual-energy X-ray absorptiometry (DXA). Milk intake was assessed using the 24-h recall method, and the levels of physical activity were examined using a questionnaire. The physical activity questions of 2009–2011 KNHANES were based on the Korean version of the International Physical Activity Questionnaire (IPAQ) short form. The subjects were classified into four groups according to milk intake and physical activity level: no milk intake + low-level physical activity group (M_noP_low), no milk intake + high-level physical activity group (M_noP_high), milk intake + low-level physical activity group (M_yesP_low), and milk intake + high-level physical activity group (M_yesP_high). The results of partial correlation controlling for age, body mass index (BMI), and energy intake showed that the BMD variables were associated significantly with physical activity in both males and females. Among males, the M_noP_low group had the lowest BMD in all BMD variables, showing a significant difference from the high-level physical activity groups (M_noP_high, M_yesP_high) by multiple logistic regression analysis. Among females, the M_yesP_high group showed a significantly higher lumbar BMD value than the other groups. The M_noP_low group had approximately 0.3 to 0.5 times lower odds ratio for median or higher BMD values, compared to M_yesP_high group. These results show that milk intake and physical activity have a combined effect on BMD, and suggest that to achieve healthy bone growth, it is important to encourage both moderate to vigorous physical activity and milk intake during adolescence.

Dairy product intake decreases bone resorption following a 12-week diet and exercise intervention in overweight and obese adolescent girls

BACKGROUND

We examined whether increased dairy intake was associated with changes in the levels of bone-related biochemical markers in overweight/obese adolescent girls undergoing a 12-week diet and exercise intervention.

METHODS

Thirty-five girls were assigned to a low dairy group (LDa; 0-2 servings/day; n = 16) or a higher dairy group (RDa; 4 servings/day; n = 19). Morning, fasted/resting blood samples were collected before and after the intervention and serum concentrations of procollagen-type-1-N-terminal-propeptide (P1NP), β-isomerized-C-terminal-cross-linking-telopeptides (β-CTX), osteocalcin (OC), 25-hydroxyvitamin-D, sclerostin and parathyroid hormone were measured.

RESULTS

At baseline, there were no significant differences between groups in any bone variable. Changes (∆) over time in β-CTΧ (p = 0.035; interaction) and OC (p = 0.015; interaction) were significantly different between groups characterized by decreases in RDa and increases in LDa. P1NP and P1NP:β-CTX ratio decreased in both groups (main time effects: p = 0.003, p = 0.041, respectively). ∆β-CTX (r = -0.37; p = 0.028) and ∆OC (r = -0.39; p = 0.021) were correlated with average number of dairy servings consumed during the study and with each other (r = 0.45; p = 0.006). ∆OC was not correlated with ∆P1NP (r = 0.19; p = 0.27).

CONCLUSIONS

Our results suggest that the osteogenic response to a diet and exercise program in this population can be improved with increased dairy intake via a decrease in bone resorption.

IMPACT

We demonstrated that bone resorption significantly decreased over the intervention period in the group consuming adequate levels of dairy products compared to the group consuming little to no dairy products. Change in bone resorption was negatively correlated with average number of dairy servings consumed during the study. Our results suggest that the osteogenic response to a diet and exercise program in this population can be improved with increased dairy intake via a decrease in bone resorption. This is the first study to date to assess changes in bone marker status following a lifestyle intervention with exercise and different intakes of dairy products in a sample of OW/OB adolescent girls. We provide evidence that increased dairy product intake is associated with beneficial changes in circulating levels of bone-related biochemical markers in these girls undergoing a 12-week lifestyle (nutrition counseling and exercise training) intervention program. The main impact of our work relates particularly to the recent changes to Canada's food guide. Using the old recommendations, we demonstrated that the inclusion of 3-4 servings of mixed dairy foods per day improved bone health (primarily as a decrease in resorption) in OW/OB adolescent girls and that this level of dairy product intake appears appropriate and should still be encouraged for this age group. We also demonstrated that adolescent girls, a group that usually does not sufficiently consume dairy products, also improved their BMI percentile and nutrient intake with the inclusion of dairy products in their diets.

Provincial Dietary Intake Study (PDIS): Micronutrient Intakes of Children in a Representative/Random Sample of 1- to <10-Year-Old Children in Two Economically Active and Urbanized Provinces in South Africa

In 1999, the National Food Consumption Survey found serious risk of dietary deficiency for a number of micronutrients in 1- to 9-year-old children in South Africa. To address these shortfalls, fortification with vitamin A, thiamine, riboflavin, niacin, vitamin B6, folic acid, iron and zinc of maize meal and bread flour was made mandatory in 2003. The aim of this study was to examine micronutrient intakes of 1- to <10-year-old children after nearly 20 years of fortification in two of the most urbanized and economically active provinces, Gauteng (GTG) and the Western Cape (WC). A multistage stratified cluster random sampling design and methodology was used. Households were visited by fieldworkers who interviewed caregivers and obtained dietary intake data by means of a multiple-pass 24-h recall. Two additional 24-h recalls were completed among a nested sample of 146 participants to adjust the single 24-h recall data of the total sample using the National Cancer Institute Method. Results show that median intake of all the fortification nutrients were above the estimated average requirement (EAR), with the only concern being folate in the WC. Between a quarter and a third of children in the WC, where maize porridge intake was significantly lower than in GTG, had a folate intake below the EAR. Nutrients that are not included in the fortification mix that remain a serious concern are calcium and vitamin D, with intake of dairy and vitamin D sources being very limited in both provinces. The improvement in micronutrient intakes of children is encouraging, however the outstanding nutrient deficiency risks need attention.

Nutritional management of lactose intolerance: the importance of diet and food labelling

Worldwide, 70% of the adult population has limited expression of lactase enzyme with a wide variation among different regions and countries. Lactase deficiency may lead to lactose intolerance (LI). Depending both on the amount of lactose ingested and on the lactase activity, people who suffer from lactose malabsorption might experience numerous gastrointestinal and extra-intestinal symptoms and manifestations. Treatment of LI mainly consists of reducing or eliminating lactose from the diet until the symptoms disappear as well as supplementing lactase, and inducing colon microbiome adaptation by probiotics. Cow’s milk is one of the major source of calcium and several other vitamins and minerals. Thus, a complete exclusion of dairy products may favor the development of bone diseases such as osteopenia and osteoporosis. Therefore, the dietetic approach has a crucial role in the management of LI patients. Additionally, the use of lactose and milk-derived products in non-dairy products (e.g., baked goods, breakfast cereals, drinks, and processed meat) has become widespread in the modern industry (the so-called “hidden lactose”). In this regard, a strict adherence to the lactose-free diet becomes challenging for LI patients, forced to continuous check of all products and food labels. In fact, lactose-free product labeling is still controversial. Considering that nowadays a specific cut-off value establishing “lactose-free” labeling policy is lacking and that there is no universal law regulating the production and commercialization of “delactosed” products, identification of specific safe and suitable products with a well-recognized lactose-free logo might help consumers. This narrative review aims to identify the dietary management for lactose intolerant people, avoiding symptoms and nutrients deficiencies, helped by the use of specific labelling to guide them to choose the safer product on the market.

Milk for Skeletal Muscle Health and Sarcopenia in Older Adults: A Narrative Review

Skeletal muscle aging manifests as a decline in muscle quantity and quality that accelerates with aging, increasing the risk of sarcopenia. Sarcopenia is characterized by a loss of muscle strength and mass, and contributes to adverse health outcomes in older adults. Intervention studies have shown that sarcopenia may be treated by higher protein intake in combination with resistance exercise (RE). In comparison, less is known about the role of whole protein-containing foods in preventing or treating sarcopenia. Liquid milk contains multiple nutrients and bioactive components that may be beneficial for muscle, including proteins for muscle anabolism that, alone or with RE, may have myoprotective properties. However, there is a lack of evidence about the role of milk and its effects on muscle aging. This narrative review considers evidence from three observational and eight intervention studies that used milk or fortified milk, with or without exercise, as an intervention to promote muscle health and function in older adults (aged 50–99 years). The observational studies showed no association between higher habitual milk consumption and muscle-related outcomes. The results of intervention studies using fortified milk in relation to elements of sarcopenia were also negative, with further inconclusive results from the studies using a combination of (fortified) milk and exercise. Although milk contains nutrients that may be myoprotective, current evidence does not show beneficial effects of milk on muscle health in older adults. This could be due to high habitual protein intakes (>1.0 g/kg BW/d) in study participants, differences in the type of milk (low-fat vs whole) and timing of milk consumption, length of interventions, as well as differences in the sarcopenia status of participants in trials. Adequately powered intervention studies of individuals likely to benefit are needed to test the effectiveness of a whole food approach, including milk, for healthy muscle aging.

Consumption of Cow's Milk in Early Childhood and Fracture Risk: A Prospective Cohort Study

Cow's milk is consumed by most North American children, yet the relationships between the volume and fat content of cow's milk consumed and childhood fracture risk are unclear. Our primary objectives in this study were to evaluate whether the volume or fat content of cow's milk consumed at 1-3 years of age was associated with the risk of fracture between 3 and 10 years of age. This was a prospective cohort study of 2,466 children enrolled in Toronto, Ontario, Canada, between 2008 and 2016. The primary exposure was volume of cow's milk consumed between the ages of 1 and 3 years, and the secondary exposure was average percentage of milk fat consumed by each child during the same period. The primary outcome was a parental report of child fracture at ages 3-10 years. In the primary and secondary adjusted analyses, no association between milk volume and fracture risk (adjusted relative risk = 1.04, 95% confidence interval: 0.87, 1.26) or between milk-fat content and fracture risk (adjusted relative risk = 1.05, 95% confidence interval: 0.84, 1.31) was observed. In this study, we did not identify a protective association of early childhood cow's milk volume or fat consumption with fracture risk in later childhood. Future prospective research is needed to understand whether cow's milk is beneficial for fracture prevention through the life course.

Expert panel consensus recommendations for diagnosis and treatment of secondary osteoporosis in children

BACKGROUND

Osteoporosis incidence in children is increasing due to the increased survival rate of patients suffering from chronic diseases and the increased use of drugs that can damage bones. Recent changes made to the definition of childhood osteoporosis, along with the lack of guidelines or national consensuses regarding its diagnosis and treatment, have resulted in a wide variability in the approaches used to treat this disease. For these reasons, the Osteogenesis Imperfecta and Childhood Osteoporosis Working Group of the Spanish Society of Pediatric Rheumatology has sounded the need for developing guidelines to standardize clinical practice with regard to this pathology.

METHODS

An expert panel comprised of 6 pediatricians and 5 rheumatologists carried out a qualitative literature review and provided recommendations based on evidence, when that was available, or on their own experience. The level of evidence was determined for each section using the Oxford Centre for Evidence-based Medicine (CEBM) system. A Delphi survey was conducted for those recommendations with an evidence level of IV or V. This survey was sent to all members of the SERPE. All recommendations that had a level of agreement higher or equal to 70% were included.

RESULTS

Fifty-one recommendations, categorized into eight sections, were obtained. Twenty-four of them presented an evidence level 4 or 5, and therefore a Delphi survey was conducted. This was submitted electronically and received a response rate of 40%. All recommendations submitted to the Delphi round obtained a level of agreement of 70% or higher and were therefore accepted.

CONCLUSION

In summary, we present herein guidelines for the prevention, diagnosis and treatment of secondary childhood osteoporosis based on the available evidence and expert clinical experience. We believe it can serve as a useful tool that will contribute to the standardization of clinical practice for this pathology. Prophylactic measures, early diagnosis and a proper therapeutic approach are essential to improving bone health, not only in children and adolescents, but also in the adults they will become in the future.

Effect of Cdx2 Polymorphism on the Relationship between Dietary Calcium Intake and Peak Bone Mass in Young Japanese Women

Studies investigating the effect of the caudal-type homeobox protein 2 (Cdx2) polymorphism in the vitamin D receptor gene and calcium intake on bone mass have shown inconsistent results. This study investigated whether the effect of calcium intake on peak bone mass is affected by Cdx2 polymorphism in young Japanese women. A cross-sectional study of 500 young women was conducted. Dietary intake was assessed by the Food Frequency Questionnaire. The osteo sono-assessment index (OSI), assessed by the qualitative ultrasound method, was used as a bone mass index. The subjects were divided into two groups by the median calcium intake. The OSI was not different among Cdx2 genotypes and between calcium groups (p = 0.960, p = 0.191, respectively). The interaction between calcium and Cdx2 genotypes on the OSI approached significance (GG versus GA and AA genotypes, p = 0.092). The difference in the OSI between calcium groups was significant in the GG genotype (p = 0.028), but not in the GA or AA genotypes (p = 0.501, p = 0.306, respectively). Adjustment for covariates (body mass index and physical activity) did not change the results. In conclusion, the relationship between dietary calcium intake and peak bone mass may vary according to Cdx2 polymorphism.

Association between dietary calcium intake and BMD in children and adolescents

AIM

Ensuring adequate calcium (Ca) intake during childhood and adolescence is critical to acquire good peak bone mass to prevent osteoporosis during older age. As one of the primary strategies to build and maintain healthy bones, we aimed to determine whether dietary Ca intake has an influence on bone mineral density (BMD) in children and adolescents.

METHODS

We conducted a cross-sectional study composed of 10,092 individuals from the National Health and Nutrition Examination Survey (NHANES). Dietary Ca intake and total BMD were as independent and dependent variables, respectively. To evaluate the association between them, we conducted weighted multivariate linear regression models and smooth curve fittings.

RESULTS

There was a significantly positive association between dietary Ca intake and total BMD. The strongest association was observed in 12-15y whites, 8-11y and 16-19y Mexican Americans, and 16-19y other race/ethnicity, in whom each quintile of calcium intake was increased. We also found there were significant inflection points in females, blacks, and 12-15y adolescents group, which means that their total BMD would decrease when the dietary Ca intake was more than 2.6-2.8 g/d.

CONCLUSIONS

This cross-sectional study indicated that a considerable proportion of children and adolescents aged 8-19 years would attain greater total BMD if they increased their dietary calcium intake. However, higher dietary calcium intake (more than 2.6-2.8 g/d) is associated with lower total BMD in females, blacks, and 12-15y adolescents group.

Association between dairy intake and fracture in an Australian-based cohort of women: a prospective study

OBJECTIVE

Given the inconsistent evidence on dairy consumption and risk of fracture, we assessed the association between milk/total dairy consumption and major osteoporotic fracture (MOF) in women from the Geelong Osteoporosis Study (GOS).

METHODS

Women aged ≥50 years (n=833) were followed from baseline (1993-1997) to date of first fracture, death or 31 December 2017, whichever occurred first. Dairy consumption was assessed by self-report at baseline and the follow-up phases. MOFs (hip, forearm, clinical spine and proximal humerus) were confirmed radiologically. Multivariable-adjusted Cox proportional hazard models were used to determine associations between milk/total dairy (milk, cheese, yoghurt, ice cream) consumption and MOFs. Cross-sectional associations between milk/total dairy consumption and serum high-sensitivity C reactive protein (hsCRP), C-terminal telopeptide (CTx) and procollagen type 1 N-terminal propeptide (P1NP) at baseline were investigated using multivariable linear regression.

RESULTS

During follow-up (11 507 person-years), 206 women had an MOF. Consuming >500 mL/d of milk was not significantly associated with increased HR for MOF. Non-milk (1.56; 95% CI 0.99 to 2.46) drinkers and consumption of ≥800 g/d total dairy (1.70; 95% CI 0.99 to 2.93) had marginally higher HR for MOF compared with consuming <250 mL/d of milk and 200-399 g/d of total dairy, respectively. Milk consumption was inversely associated with serum hsCRP and CTx, but total dairy consumption was not associated with these serum markers.

CONCLUSION

Higher milk consumption did not increase the risk for MOF in older women. However, a trend for increased MOF was detected in zero milk and higher total dairy consuming women.

Effects of milk powder intervention on bone mineral density and indicators related to bone metabolism in Chinese adolescents

The study is to determine the effects of milk powder on bone density and metabolism in healthy adolescents. Vitamin D and calcium supplements increased IGF-1 but did not affect bone mineralization or turnover. Higher vitamin D in combination with sufficient calcium supplementation in such populations requires attention.

INTRODUCTION

Both calcium and vitamin D play an important role in bone mineralization in adolescents.

METHODS

In this one and a half-year randomized controlled trial, 232 participants (aged 12-15 years) were randomly assigned to three intervention groups receiving milk powder fortified with vitamin D 400 IU plus calcium 300, or 600, or 900 mg [Ca3D (n = 54), Ca6D (n = 56), and Ca9D (n = 49)], or one control group maintaining habitual diet [control (n = 73)]. Bone turnover markers, serum intact PTH, 25(OH)D, and IGF-1 levels were measured at baseline and one and a half years, and bone mineral contents and bone areal mineral density were measured by Dual-energy X-ray absorptiometry (DXA) at baseline, one year, and one and a half years.

RESULTS

Baseline average serum 25(OH)D level and calcium intake were 29.4 nmol/L and 363.5 mg/day, respectively. There was a significant increase in bone turnover, total body, hip, lumbar spine bone mineral density (BMD), and total body BMC as well as slight fluctuations in 25(OH)D levels over one and a half years without between-group differences. Significantly decreased serum PTH level was only observed in the Ca6D group (31%, p < 0.0001), in which the intervention effect was also significant (p = 0.0029) compared with the control group. IGF-1 levels increased significantly in all intervention groups (18.5 to 22.8%, p < 0.05) but decreased in the control group (16.5%, p < 0.05), and the group by time interaction was also significant (p = 0.0029).

CONCLUSIONS

Our study showed that in healthy adolescents with low vitamin D status and calcium intake, mild vitamin D and mild to modest calcium supplements increased IGF-1 but did not affect bone mineralization or turnover. Higher vitamin D in combination with sufficient calcium supplementation in such populations requires attention.

Participation in the School Milk Program Contributes to Increased Milk Consumption and Dietary Nutrient Intake by Middle School Students in South Korea

Milk is considered to be one of the main food sources of calcium for promoting growth and bone health in children and adolescents. This study investigated whether or not participation in a school milk program affected milk consumption and nutrient intake by middle school students in South Korea. In total, 692 middle school students aged 13–16 years old were enrolled in two groups: the school milk program participant group (n = 346) and the non-participant group (n = 346). The survey examined normal milk consumption status in both groups. The diet record method was applied to analyze the amount of nutrient intake levels. Milk/dairy product consumption was significantly higher in the school milk program participant group for both boys and girls (p < 0.001). The school milk program participant group also generally showed higher energy and dietary nutrient intake levels as compared to the non-participant group for both genders (p < 0.05). No differences were observed in milk consumption at home or outside school, and calcium intake from animal-derived foods was higher in the school milk program participant group (p < 0.001). Therefore, it can be assumed that participating in the school milk program directly resulted in higher calcium intake. Hence, we can report that participating in the school milk program contributes to increased milk consumption and improved the overall nutrient intake.

Effects of Dairy Product Consumption on Height and Bone Mineral Content in Children: A Systematic Review of Controlled Trials

There is a physiological basis for the roles of selected nutrients, especially proteins, calcium, and vitamin D, in growth and development, which are at a maximum during the pediatric period. Milk and dairy products are particularly rich in this group of nutrients. The present systematic review summarizes the available evidence relating dairy product intake with linear growth and bone mineral content in childhood and adolescence. A search was conducted in the MEDLINE (via PubMed) and SCOPUS databases following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and included intervention-controlled clinical trials with dairy products in children from 1 January, 1926 to 30 June, 2018. The risk of bias for each study was assessed using the Cochrane methodology. The number of study participants, the type of study and doses, the major outcomes, and the key results of the 13 articles included in the review are reported. The present systematic review shows that supplementing the usual diet with dairy products significantly increases bone mineral content during childhood. However, the results regarding a possible relation between dairy product consumption and linear growth are inconclusive.

Australian children and adolescents who were drinkers of plain and flavored milk had the highest intakes of milk, total dairy, and calcium

Dairy is important for children and adolescents' bone development and nutritional needs, and it is not known how the type of milk consumed relates to overall dietary intakes. This study assessed the hypothesis that Australian children and adolescents who drink milk have greater milk, dairy, and micronutrient intakes compared to those who consume milk in other ways or avoid milk. A secondary analysis using day 1 data from the 2011-2012 National Nutrition and Physical Activity Survey was performed (n = 2812, 2-18 years). Children were classified as plain or flavored milk drinkers, other milk drinkers (eg, smoothies, milkshakes), nondrinkers of milk (eg. on cereal), or milk avoiders. Intakes of total dairy, milk, calcium, free sugars, and sugar-sweetened beverages were determined and adjusted for confounders. Milk consumption was popular (81%), and the majority (63%) of milk consumers were drinkers, and of those, 46% were plain, 32% were flavored, and 21% were other milk drinkers. Flavored and plain milk drinkers had higher total daily milk (480, 95% confidence interval [CI] 459-501 and 445, 95% CI 427-462 g, respectively), dairy (2.8, 95% CI 2.7-2.9 and 2.6, 95% CI 2.5-2.7 servings, respectively), and calcium (1049 ± 18 and 980 ± 15 mg, respectively) intakes than all other groups. Plain milk drinkers (10.7%, SD 6.2%) had a lower proportion of daily energy from free sugars than all other groups, but there was no difference in free sugars intake between plain and flavored milk drinkers, and there were no differences in anthropometric measures across groups. Plain and flavored milk drinkers and nondrinkers of milk had the lowest prevalence of sugar-sweetened beverages intake (P < .001). Plain milk drinkers followed by flavored milk drinkers had the most favorable milk, dairy, and nutrient intakes.

Lactose Intolerance and Bone Health: The Challenge of Ensuring Adequate Calcium Intake

Calcium is an important nutrient with impact upon many biological systems, most notably bone. Ensuring adequate calcium intake throughout the lifespan is essential to building and maintaining bone. Lactose intolerance may predispose individuals to low calcium intake as the number of lactose-free, calcium-rich food sources is limited. In this review, we summarize data from human and animal studies on the influence of lactose and lactase deficiency on calcium absorption and bone health. Based on the available evidence, neither dietary lactose nor lactase deficiency have a significant impact on calcium absorption in adult humans. However, lactose intolerance may lead to reduced bone density and fragility fractures when accompanied by decreased intake or avoidance of dairy. Recently published human trials and meta-analyses suggest a weak but significant association between dairy consumption and bone health, particularly in children. Given the availability of simple dietary approaches to building lactose tolerance and the nutritional deficiencies associated with dairy avoidance, multiple public health organizations recommend that all individuals—including those that are lactose intolerant—consume three servings of dairy per day to ensure adequate nutrient intakes and optimal bone health.

Lactose-Free Dairy Products: Market Developments, Production, Nutrition and Health Benefits

Lactose-free dairy is able to provide the essential nutrients present in regular dairy products, like calcium and vitamins, to those that are not able to digest lactose. This product category currently has a wide and growing health appeal to consumers. In recent years, the quality and product variety in the lactose-free dairy segment has been increasing significantly, giving consumers more tempting products to decide from. As a result, lactose-free dairy is now the fastest growing market in the dairy industry. This review discusses the market developments and production possibilities and issues related to the wide variation of lactose-free dairy products that are currently available. Additionally, the health benefits that lactose-free dairy may offer compared to dairy avoidance are illustrated.

Dairy foods and bone health throughout the lifespan: a critical appraisal of the evidence

The consumption of high-Ca, high-protein dairy foods (i.e. milk, cheese, yogurt) is advocated for bone health across the lifespan to reduce the risk of low-trauma fractures. However, to date, the anti-fracture efficacy of dairy food consumption has not been demonstrated in randomised controlled trials but inferred from cross-sectional and prospective studies. The anti-fracture efficacy of dairy food consumption is plausible, but testing this requires a robust study design to ensure outcomes are suitably answering this important public health question. The evidence of skeletal benefits of dairy food consumption is equivocal, not because it may not be efficacious but because the study design and execution are often inadequate. The key issues are compliance with dietary intervention, dropouts, sample sizes and most importantly lack of deficiency before intervention. Without careful appraisal of the design and execution of available studies, precarious interpretations of outcomes may be made from these poorly designed or executed studies, without consideration of how study design may be improved. Dairy food interventions in children are further hampered by heterogeneity in growth: in particular sex and maturity-related differences in the magnitude, timing, location and surface-specific site of bone accrual. Outcomes of studies combining children of different sexes and maturity status may be masked or exaggerated by these differences in growth, so inaccurate conclusions are drawn from results. Until these critical issues in study design are considered in future dairy food interventions, the anti-fracture efficacy of dairy food consumption may remain unknown and continue to be based on conjecture.

Milk consumption, dietary calcium intake and nutrient patterns from adolescence to early adulthood and its effect on bone mass: the 1993 Pelotas (Brazil) birth cohort

The objective of this study is to evaluate the effect of milk consumption, dietary calcium intake and nutrient patterns (bone-friendly and unfriendly patterns) from late adolescence to early adulthood, on bone at 22 years of age. Cross-sectional analysis was performed with 3,109 participants from 1993 Pelotas (Brazil) birth cohort in the follow-ups of 18 and 22 years of age. Bone mineral density (BMD) of the lumbar spine, right femur and whole body were assessed at 22 years using a dual-energy X-ray absorptiometry (DXA). The exposure variables (dietary calcium, milk and nutrient patterns) were created by combining the consumption frequencies between the two follow-ups (always low, moderate, high, increase or decrease). Multiple linear regressions were performed, stratified by sex. In the right femur site, men classified into the “always high” (mean = 1.148g/cm²; 95%CI: 1.116; 1.181) and “increased” categories of milk consumption (mean = 1.154g/cm²; 95%CI: 1.135; 1.174) presented a slightly low BMD comparing with low (mean = 1.190g/cm²; 95%CI: 1.165; 1.215) and moderate (mean = 1.191g/cm²; 95%CI: 1.171; 1.210) categories. In addition, men always classified in the highest tertile of the “bone-unfriendly” pattern presented the lowest mean of whole body BMD (mean = 1.25g/cm²; 95%CI: 1.243; 1.266). No associations were observed between the categories of dietary calcium intake and “bone-friendly” pattern and each of the three BMD outcomes. These results point to the fact that diets composed of inhibiting foods/nutrients can contribute negatively to bone health.

Cow's Milk Consumption and Health: A Health Professional's Guide

The most recent scientific evidence supports the consumption of cow's milk and dairy products as part of a balanced diet. However, these days, the public and practicing physicans are exposed to a stream of inconsistent (and often misleading) information regarding the relationship between cow's milk intake and health in the lay press and in the media. The purpose of this article, in this context, is to facilitate doctor-patient communication on this topic, providing physicians with a series of structured answers to frequently asked patient questions. The answers range from milk and milk-derived products' nutritional function across the life span, to their relationship with diseases such as osteoporosis and cancer, to lactose intolerance and milk allergy, and have been prepared by a panel of experts from the Italian medical and nutritional scientific community. When consumed according to appropriate national guidelines, milk and its derivatives contribute essential micro- and macronutrients to the diet, especially in infancy and childhood where bone mass growth is in a critical phase. Furthermore, preliminary evidence suggests potentially protective effects of milk against overweight, obesity, diabetes, and cardiovascular disease, while no clear data suggest a significant association between milk intake and cancer. Overall, current scientific literature suggests that an appropriate consumption of milk and its derivatives, according to available nutritional guidelines, may be beneficial across all age groups, with the exception of specific medical conditions such as lactose intolerance or milk protein allergy. Key teaching points: Milk and its derivatives contribute essential micro and macronutrients to the diet, when consumed according to appropriate national guidelines, especially in infancy and childhood where bone mass growth is in a critical phase. Preliminary evidence suggests potentially protective effects of milk against overweight, obesity, diabetes and cardiovascular disease No clear data are available about the association between milk intake and cancer. Current scientific literature suggests that an appropriate consumption of milk and its derivatives may be beneficial at all ages, with the exception of specific medical conditions such as lactose intolerance or milk protein allergy.

Do Chinese Preschool Children Eat a Sufficiently Diverse Diet? A Cross-Sectional Study in China

BACKGROUND

This study aimed to comprehensively evaluate dietary diversity and its associated factors in Chinese preschoolers and explore whether the daily food consumption of children with different dietary diversity-associated characteristics met recommended dietary amounts.

METHODS

A cross-sectional study covering seven cities and two villages was conducted and included 697 preschool children aged 3⁻7 years old. Dietary diversity score (DDS) and DDS 10 were calculated based on 24-h dietary recall. The food-intake differences among children with different DDS 10 predictors were examined.

RESULTS

The mean DDS and DDS 10 in Chinese preschool children were 7.4 ± 1.5 (ranged from 3 to 9) and 7.0 ± 3 (ranged from 3 to 9) respectively. Positive predictors of dietary diversity included residing in an urban environment, a higher household expenditure on children’s food, and a higher frequency of eating outside. Food-intake differences existed among the predictors.

CONCLUSIONS

Education and intervention should be strengthened to improve the dietary diversity of preschool children, especially in rural areas. The overall dietary pattern of children requires attention, which means not only increasing dietary diversity but also avoiding an unbalanced diet.

School-based exercise interventions effectively increase bone mineralization in children and adolescents

Osteoporosis and fragility fractures have become major global public health concerns, and they can be prevented by maximizing peak bone mass during childhood and adolescence with weight-bearing physical activity, which can result in stronger and healthier bones that significantly decrease the risk of osteoporosis and fragility fractures in adulthood and the elderly years. From a public health perspective, implementing weight-bearing physical activity for children and adolescents is best achieved with school-based exercise interventions, and a review of school-based exercise interventions was conducted to determine their effectiveness in increasing bone mineral density (BMD) and/or bone mineral content (BMC). Seventeen studies were reviewed, all school-based exercise interventions utilized jumping exercises, and 15 of the 17 studies found at least one significant increase in measures of BMD and/or BMC for the total body, and/or at the hip, vertebrae, and/or wrist. One study that found no significant differences did report significant increases in bone structural strength, and the other study with no significant differences had exercises that measured and reported the lowest ground reaction forces (GRFs) of only 2–3 times body weight (BW), whereas the other studies that showed significant increase(s) in BMD and/or BMC had exercise with measured and reported GRFs ranging from 3.5 × to 8.8 × BW. School-based exercise interventions are time- and cost-efficient and effective in increasing BMD and/or BMC in children and adolescents, but must incorporate high-intensity exercise, such as high-impact jumping of sufficient GRFs, in order to significantly increase bone mineralization for osteoporosis and fragility fracture prevention later in life.