Effect of increasing dietary calcium through supplements and dairy food on body weight and body composition: a meta-analysis of randomised controlled trials. Br J Nutr. 2015;114:1013-1025. [PMID: 26234296 DOI: 10.1017/s0007114515001518]

Association between abdominal obesity and nutritional supplement use among Iranian adults in the Shahedieh cohort study

The relationship between the use of supplements and the presence of abdominal obesity is a topic that is currently being debated. The purpose of the present study was to evaluate the existence of such an association. The current cross-sectional investigation included a population of 9878 individuals who were the focus of the study's initial phase in the Shahedieh cohort study, conducted in Yazd, Iran. Waist circumference was measured with the help of an inflexible tape measure. In addition, the data regarding the consumption of various supplements, including multivitamins, folic acid, ferric compounds, omega 3, calcium, vitamin D, zinc, and other supplements, were collected through interviews conducted by trained interviewers. Among the entire sample, 4785 individuals (50.6%) were found to have abdominal obesity, while 4093 individuals (43.3%) reported using at least one type of supplements. In the simple regression analysis, all of the supplements, except for multivitamins and zinc, were identified as adverse factors for abdominal obesity. However, in the multivariable regression analysis, only ferric compounds remained significant as a protective factor (OR = 0.73, 95%CI: 0.57‒0.94). The findings of this study suggest that dietary supplements, particularly ferric compounds, may have implications for managing abdominal obesity. These findings could inform public health strategies by incorporating ferric compound supplementation into dietary interventions aimed at reducing abdominal obesity prevalence. Furthermore, the potential clinical application of ferric compounds highlights the need for integrating nutritional approaches in obesity management programs. However, longitudinal studies are needed to establish causal relationships and confirm the long-term effectiveness and safety of such interventions.

Dietary Calcium-to-Phosphorous Ratio, Metabolic Risk Factors and Lipid Accumulation Product, Skeletal Muscle Mass, and Visceral Fat Area Among Healthy Young Individuals

BACKGROUND

Numerous studies have revealed the role of low dietary calcium-to-phosphorous ratio and low bone health. However, its possible role in visceral adiposity, skeletal muscle mass (SMM), and metabolic parameters has not been investigated before. Therefore, the aim of the current cross-sectional study was to evaluate the relation between dietary calcium-to-phosphorous ratio, metabolic risk factors, SMM, and visceral fat area (VFA) among physically active young individuals.

METHODS

In the current study, the sample was composed of 391 healthy young individuals (e.g., 205 men and 186 women), aged between 20 and 35 years old, who were engaged in moderate physical activity for at least 4 hr per week and were recruited thorough cluster sampling from seven sport clubs. Anthropometric measurements were performed, and VFA and SMM index (SMI) were calculated. Biochemical assays were also performed by standard kits. Data were analyzed by one-way analysis of variance, analysis of co-variance, and multinomial logistic regression analysis using SPSS software.

RESULTS

Those in the fourth quartile of dietary calcium-to-phosphorous ratio were more likely to have lower VFA (odds ratio [OR] = 0.98; 95% confidence interval [CI] [0.97, 0.99]; p = .023) and a nonsignificantly higher SMI (OR = 1.15; 95% CI [0.99, 1.34]; p = .058) after adjustment for the effects of confounders (e.g., age, gender, body mass index, physical activity level, dietary energy intake). Also, being in the third quartile of dietary calcium-to-phosphorous ratio made the subjects more susceptible to have lower insulin concentration (OR = 0.99; 95% CI [0.88, 0.93]; p = .026) in the adjusted model.

CONCLUSION

The findings of the current study revealed that a higher dietary calcium-to-phosphorous ratio in the habitual diet was negatively associated with visceral adiposity and insulin concentrations and higher SMM among physically active young individuals. Further interventional studies are required to confer causality that was not inferable in the current study because of cross-sectional design.

Calcium supplementation for people with overweight or obesity

BACKGROUND

Obesity is a major health problem worldwide as it can lead to high blood pressure, heart disease, stroke, diabetes, and insulin resistance. The prevalence of overweight and obesity is increasing worldwide across different age groups. There is evidence of an inverse relationship between calcium intake and body weight. The clinical relevance of a small reduction in body weight has been questioned. However, at a population level, a small effect could mitigate the observed global trends.

OBJECTIVES

To assess the effects of calcium supplementation on weight loss in individuals living with overweight or obesity.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, LILACS (Latin American and Caribbean Health Science Information database), and two clinical trials registries. The date of the last search of all databases (except Embase) was 10 May 2023. No language restrictions were applied.

SELECTION CRITERIA

We included randomised controlled trials evaluating the effect of calcium in participants with overweight or obesity of any age or gender. We excluded studies in participants with absorption problems. We included studies of any dose with a minimum duration of two months. We included the following comparisons: calcium supplementation versus placebo, calcium-fortified food or beverage versus placebo, or calcium-fortified food or beverage versus non-calcium-fortified food or beverage. We excluded studies that evaluated the effect of calcium and vitamin D or mixed minerals compared to placebo.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Our primary outcomes were body weight, health-related quality of life, and adverse events. Our secondary outcomes were anthropometric measures other than body weight, all-cause mortality, and morbidity.

MAIN RESULTS

We found 18 studies that evaluated the effect of calcium compared to placebo or control, with a total of 1873 randomised participants (950 participants in the calcium supplementation groups and 923 in the control groups). All included studies gave oral calcium supplementation as the intervention. We did not find any studies evaluating calcium-fortified foods. We excluded 38 studies, identified four ongoing studies, and listed one study as 'awaiting classification'. Sixteen studies compared calcium supplementation to placebo; two studies compared different doses of calcium supplementation. Doses ranged from very low (0.162 g of calcium/day) to high (1.5 g of calcium/day). Most studies were performed in the USA and Iran, lasted less than six months, and included only women. Low-certainty evidence suggests that calcium supplementation compared to placebo or control may result in little to no difference in body weight (mean difference (MD) -0.15 kg, 95% confidence interval (CI) -0.55 to 0.24; P = 0.45, I2 = 46%; 17 studies, 1317 participants; low-certainty evidence). We downgraded the certainty of the evidence by two levels for risk of bias and heterogeneity. None of the included studies reported health-related quality of life, all-cause mortality, or morbidity/complications as outcomes. Only five studies assessed or reported adverse events. Low-certainty evidence suggests a low frequency of adverse events, with no clear difference between intervention and control groups. Moderate-certainty evidence shows that calcium supplementation compared to placebo or control probably results in a small reduction in body mass index (BMI) (MD -0.18 kg/m2,95% CI -0.22 to -0.13; P < 0.001, I2 = 0%; 9 studies, 731 participants) and waist circumference (MD -0.51 cm, 95% CI -0.72 to -0.29; P < 0.001, I2 = 0%; 6 studies, 273 participants). Low-certainty evidence suggests that calcium supplementation compared to placebo or control may result in a small reduction in body fat mass (MD -0.34 kg, 95% CI -0.73 to 0.05; P < 0.001, I2 = 97%; 12 studies, 812 participants).

AUTHORS' CONCLUSIONS

Calcium supplementation for eight weeks to 24 months may result in little to no difference in body weight in people with overweight or obesity. The current evidence is of low certainty, due to concerns regarding risk of bias and statistical heterogeneity. We found that the degree of heterogeneity might be partly explained by calcium dosage, the presence or absence of a co-intervention, and whether an intention-to-treat analysis was pursued. While our analyses suggest that calcium supplementation may result in a small reduction in BMI, waist circumference, and fat mass, this evidence is of low to moderate certainty. Future studies could investigate the effect of calcium supplementation on lean body mass to explore if there is a change in body composition.

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.

Evidence-Based Eating Patterns and Behavior Changes to Limit Excessive Gestational Weight Gain: A Scoping Review

BACKGROUND

International prenatal care guidelines set a standard for clinicians to discuss gestational weight gain with their patients along with the complications associated with prepregnancy obesity and excessive gestational weight gain. Clinicians often lack evidence-based eating, nutrition, and activity strategies to share with patients.

METHODS

This systematic review aimed to find eating patterns and behaviors that could be used safely during pregnancy to limit excessive gestational weight gain. PubMed, MEDLINE, and Web of Science were searched for research or systematic reviews performed in the United States or Canada and published in English from 2013 to 2023. Keyword search terms included weight, manage, behavior, strategy, strategies, gestational weight gain, and nutrition. Excluded research used pediatric or adolescent populations, restrictive diets, such as no carbohydrate or no fat diets, fasting, bariatric surgery, weight loss medications, private industry or profit-earning programs using food brands, or specific diet programs.

RESULTS

A total of 844 abstracts were retrieved, with 103 full-text studies reviewed. Behaviors had to be useful for maintaining a healthy gestational weight gain and had to be safe for use during pregnancy. Behaviors useful during pregnancy included meal planning, home meal preparation, portion control, using diets such as the Mediterranean diet, the low-glycemic index diet, and the Dietary Approaches to Stop Hypertension diet (DASH), regular physical activity, sleeping 6-7 h a night, mindful eating, intuitive eating, and regular seif-weighing.

CONCLUSION

The evidence-based strategies outlined in this review are safe for use during pregnancy and can assist patients in avoiding excessive gestational weight gain while maintaining the nutrition needed for healthy fetal growth.

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.

An eight-week randomized intervention study on Korean adults to evaluate the effect of milk intake on obesity

The anti-obesity effect of milk intake has been suggested via a variety of designed studies, but findings of obesity interventions for Korean adults are scarcely reported. The study aimed to investigate the anti-obesity effect of cow milk in Korean adults with an 8-wk randomized intervention. A total of 121 adults overweight aged 19 to 60 yr old were randomly assigned to 1 of the 2 groups: milk or control. During the intervention, both groups were encouraged 500 kcal of restriction a day, and the milk group consumed 200 mL of milk twice a day; the same energy intake as the control group, including milk intake, was recommended for 8 wk. We detected no significant differences in body weight (BW) and body mass index (BMI) between the milk and control groups during the 8-wk intervention, although the changes in BW and BMI of those within the milk group were significant. High-density lipoprotein cholesterol levels and serum calcium levels increased significantly in the milk group compared with the control group. Calcium, phosphorus, vitamin A, and riboflavin intakes increased significantly, when compared with the control. In conclusion, 8-wk milk consumption had no effect on weight loss and BMI change but improved some blood biomarkers and nutrient intake in Korean adults who were overweight. To evaluate the effect of milk on obesity reduction, well-designed, long-term, and large-scale studies are needed.

Consumption of Dairy Products and the Risk of Overweight or Obesity, Hypertension, and Type 2 Diabetes Mellitus: A Dose-Response Meta-Analysis and Systematic Review of Cohort Studies

Dairy products have been suggested to be related to the prevention of overweight or obesity, hypertension, and type 2 diabetes mellitus (T2DM). These associations are currently controversial, however, and a systematic quantitative meta-analysis is lacking. In this study, we examined the associations between dairy products and the risk of overweight or obesity, hypertension, and T2DM and tested for dose-response relations. We comprehensively searched PubMed, Embase, and Web of Science up to April 2021. Cohort studies were included if dairy food consumption was reported at a minimum of 3 levels or as continuous variables, and the associations were assessed with overweight or obesity, hypertension, and T2DM. Summary RRs and 95% CIs were estimated for the dose-response association. Restricted cubic splines were used to evaluate the linear or nonlinear relations. Among the 9887 articles retrieved, 42 articles were included. For overweight or obesity, a linear association was observed for total dairy, milk, and yogurt. The risk decreased by 25%, 7%, and 12% per 200-g/d increase for total dairy, high-fat dairy, and milk, respectively, and by 13% per 50-g/d increment of yogurt. For hypertension, a nonlinear association was observed with total dairy, whereas significant inverse associations were found for low-fat dairy (RR: 0.94; 95% CI: 0.90, 0.98) and milk (RR: 0.94; 95% CI: 0.92, 0.97) per 200-g/d intake increase. For T2DM, all types of dairy food consumption except for milk and low-fat dairy products showed nonlinear associations, with total dairy and yogurt intake associated with 3% and 7% lower risk per 200-g/d and 50-g/d intake increase, respectively. In conclusion, our study suggests that total dairy is associated with a low risk of overweight or obesity, hypertension, and T2DM, especially milk and yogurt for overweight or obesity, low-fat dairy and milk for hypertension, and yogurt for T2DM.

Human body weight, nutrients, and foods: a scoping review

Background

The aim of this article (scoping review) is to elucidate the current knowledge for the potential role of body weight for setting and updating Dietary Reference Values (DRVs) and Food-Based Dietary Guidelines (FBDGs). The following research questions were formulated:What is known about the association between intakes of specific nutrient and/or foods (exposure/intervention) and body weight (outcome) in the general population?What is known about the association between body weight (exposure) and intakes of specific nutrient and/or foods (outcomes)?Is there any evidence suggesting specific effects of foods or nutrients on body weight independent of caloric content?

Methods

To identify potentially relevant articles, PubMed was searched from January 1, 2011 to June 9, 2021. The search strategy was drafted by the NNR2022 Committee. The final results were exported into EndNote. Systematic reviews (SRs), scoping reviews (ScRs), reviews, and meta-analyses (MAs) on the topic 'Body weight' published between January 1, 2011 and June 9, 2021, including human participants from the general population, in English or Scandinavian language (Norwegian, Swedish, or Danish), were considered eligible.

Main findings

First, the overall body of evidence based on findings from SRs and MAs of observational and clinical studies indicates that changes in intakes of specific nutrients (sugar, fiber, and fat) and/or foods (sugar sweetened beverages, fiber rich food, and vegetables) are associated with modest or small short-term changes (0.3-1.3 kg) in body weight in the general population (with or without obesity/overweight), while long-term studies are generally lacking. Second, no study in our search assessed any association between body weight (exposure) and intakes of specific nutrients or foods (outcomes). Third, limited evidence suggests, but does not prove, that some foods or nutrients may have specific effects on body weight or body weight measures independent of caloric content (e.g. nuts and dairy). These findings may inform the setting and updating of DRVs and FBDGs in NNR2022.

Protective effect on bone of nacre supplementation in ovariectomized rats

Nacre has emerged as a beneficial natural product for bone cells and tissues, but its effect was only studied by gavage in the ovariectomized mouse model. We sought to assess the antiosteoporotic effect of nacre through a nutritional supplementation in the ovariectomized rat model. Sixteen‐week‐old female Wistar rats were either Sham‐operated or bilateral ovariectomized (OVX) and then fed with standard diet (Sham and OVX groups) or standard diet supplemented with either 0.25% CaCO₃ or nacre (OVX CaCO₃ and OVX Nacre group, respectively) for 28 days (n = 10/group). The bone microarchitecture was assessed at appendicular and axial bones by micro‐computed tomography (μCT). Histomorphometric analysis was performed to determine cellular and dynamic bone parameters. Bone metabolism was also evaluated by biochemical markers and gene expression levels. Nacre‐based diet prevented the OVX‐induced bone loss better than that of the CaCO₃ supplement, given the significant changes in trabecular bone volume fraction (BV/TV) both at the femoral distal metaphysis (difference, 35%; p = 0.004) and at the second lumbar spine (difference, 11%; p = 0.01). Trabecular osteoclast surfaces (Oc.S/BS) were also 1.5‐fold lower at the tibial proximal metaphysis in OVX Nacre group compared with OVX CaCO₃ group (p = 0.02)_. By principal component analysis (PCA), OVX Nacre group formed a cluster away from OVX group and with a trend closest to Sham group. These data were consistent with biological measurements demonstrating a positive profile related to nacre supplementation, which blunted an increase in serum CTX level and enhanced serum P1NP secretion 14 days post‐OVX compared with CaCO₃ supplementation. Bmp2 mRNA expression in OVX Nacre group was +1.76‐fold (p = 0.004) and +1.30‐fold (p = 0.20) compared with OVX and OVX CaCO₃ groups, respectively. We conclude that supplementation with nacre could effectively limit bone loss induced by estrogen deficiency just after OVX in rats by modulating the negative imbalance of bone turnover. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Effect of β3-adrenergic receptor gene polymorphism and lifestyle on overweight Japanese rural residents: A cross-sectional study

Objectives

The β3-adrenergic receptor (ADRB3) gene polymorphism has been implicated in obesity. Therefore, the contribution of ADRB3 Trp64Arg polymorphism to obesity-related indicators was investigated, taking into account the lifestyle-related factors in a Japanese rural population.

Methods

A total of 600 Japanese adults aged ≥40 years in a population-based cohort study were analyzed. The ADRB3 polymorphism was determined using peripheral blood samples. Associations between genotype and body mass index (BMI), waist circumference (WC), and body fat (BF) percentage were examined, adjusting for lifestyle-related factors, including daily nutrient intake.

Results

The frequency of Arg64 allele carriers was 36%. There was no significant difference in BMI, WC, or BF between the groups with or without the Trp64Arg polymorphism. Multivariable logistic regression analysis showed that the Trp64Arg polymorphism was not associated with these three indicators, but lifestyle factors including physical inactivity, higher energy and sodium consumption, and less animal protein intake were significantly related to increased WC and BF percentages.

Conclusions

The Trp64Arg polymorphism of ADRB3 gene did not contribute to increased BMI, WC, or BF. However, lifestyle-related factors impacted these indicators in middle-aged and older Japanese individuals living in rural areas.

Consumption of Dairy Foods and Cardiovascular Disease: A Systematic Review

Limited consumption of dairy foods and use of low-fat products is recommended for cardiovascular (CV) prevention; however, other features besides fat content modulate their metabolic effects. We analyze updated evidence on the relationship of different dairy products (low/full-fat dairy, milk, cheese, yogurt) with CVD by reviewing meta-analyses of cohort studies and individual prospective cohort studies with CV hard endpoints (CVD/CHD incidence/mortality), together with meta-analyses of randomized controlled trials exploring the effect of dairy on major CV risk factors. The analyses provide evidence that moderate dairy consumption (up to 200 g/day, globally) has no detrimental effects on CV health and that their effect depends more on the food type (cheese, yogurt, milk) than on the fat content. These data expand current knowledge and may inform revision of current guidelines for CVD prevention.

The Role of Bovine and Non-Bovine Milk in Cardiometabolic Health: Should We Raise the "Baa"?

Although causality is yet to be confirmed, a considerable volume of research has explored the relationships between cow milk consumption, type II diabetes, and cardiovascular disease. Contrastingly, it has not been comprehensively examined whether milk of non-bovine origin can provide cardiometabolic protection. This narrative review outlines the marked differences in macronutrient composition, particularly protein and lipid content, and discusses how whole milk product (and individual milk ingredients) from different species could impact cardiometabolic health. There is some data, although primarily from compositional analyses, animal studies, and acute clinical trials, that non-bovine milk (notably sheep and goat milk) could be a viable substitute to cow milk for the maintenance, or enhancement, of cardiometabolic health. With a high content of medium-chain triglycerides, conjugated linoleic acid, leucine, and essential minerals, sheep milk could assist in the prevention of metabolic-related disorders. Similarly, albeit with a lower content of such functional compounds relative to sheep milk, goat and buffalo milk could be plausible counterparts to cow milk. However, the evidence required to generate nutritional recommendations for ‘non-bovine milk’ is currently lacking. Longer-term randomised controlled trials must assess how the bioactive ingredients of different species’ milks collectively influence biomarkers of, and subsequently incidence of, cardiometabolic health.

Nonsurgical weight loss interventions: A systematic review of systematic reviews and meta-analyses

Access to bariatric surgery to treat obesity is limited and has long wait times. Many adults are seeking nonsurgical weight loss support. Our study objective was to conduct a systematic review of nonsurgical weight loss interventions. PubMed, EMBASE, CINAHL, PsycInfo, and the CochraneLibrary were searched. Inclusion criteria were adults 18 + with a BMI > 25 enrolled in minimum a 3-month nonsurgical weight loss intervention. Studies were independently extracted and assessed for quality using A MeaSurement Tool to Assess systematic Reviews 2 (AMSTAR2). Pooled analyses were extracted, graded for evidence quality, and summarized. A total of 1065 studies were assessed for eligibility; 815 screened and 236 full-texts assessed. Sixty-four meta-analyses met eligibility criteria: 1180 RCTs with 184,605 study participants. Studies were categorized as diets (n = 13), combination therapies (n = 10), alternative (n = 16), technology (n = 10), behavioral (n = 5), physical activity (n = 6), and pharmacotherapy (n = 3). In 80% of studies, significant weight losses were reported ranging from 0.34-8.73 k in favor of the intervention. The most effective nonsurgical weight loss interventions were diets, either low-carbohydrate or low-fat diets, followed for 6 months; combination therapy including meal replacements plus enhanced support; and pharmacotherapy followed for 12 months. Although significant weight losses were reported for other types of interventions such as physical activity and technology, the majority of studies reported weight losses less than 2 kgs.

Dairy product consumption and incident prediabetes in Dutch middle-aged adults: the Hoorn Studies prospective cohort

Purpose

Our aim was to investigate prospective associations of consumption of total dairy and dairy types with incident prediabetes in a Dutch population-based study.

Methods

Two enrolment waves of the Hoorn Studies were harmonized, resulting in an analytic sample of 2262 participants without (pre-) diabetes at enrolment (mean age 56 ± 7.3 years; 50% male). Baseline dietary intake was assessed by validated food frequency questionnaires. Relative risks (RRs) were calculated between dairy, fermented dairy, milk, yogurt (all total/high/low fat), cream and ice cream and prediabetes. Additionally, substituting one serving/day of dairy types associated with prediabetes with alternative dairy types was analysed.

Results

During a mean 6.4 ± 0.7 years of follow-up, 810 participants (35.9%) developed prediabetes. High fat fermented dairy, cheese and high fat cheese were associated with a 17% (RR 0.83, 95% CI 0.69–0.99, p_trend = 0.04), 14% (RR 0.86, 95% CI 0.73–1.02, p_trend = 0.04) and 21% (RR 0.79, 95% CI 0.66–0.94, p_trend = 0.01) lower risk of incident prediabetes, respectively, in top compared to bottom quartiles, after adjustment for confounders. High fat cheese consumption was continuously associated with lower prediabetes risk (RR_servings/day 0.94, 95% CI 0.88–1.00, p = 0.04). Total dairy and other dairy types were not associated with prediabetes risk in adjusted models, irrespective of fat content (RR ~ 1). Replacing high fat cheese with alternative dairy types was not associated with prediabetes risk.

Conclusion

The highest intake of high fat fermented dairy, cheese and high fat cheese were associated with a lower risk of prediabetes, whereas other dairy types were not associated. Cheese seems to be inversely associated with type 2 diabetes risk, despite high levels of saturated fatty acids and sodium.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00394-021-02626-9.

Calcium Intake Is Inversely Related to Risk of Obesity among American Young Adults over a 30-Year Follow-Up

BACKGROUND

Calcium (Ca) is an essential nutrient that may play an important role in weight maintenance through its involvement in energy or lipid metabolism. However, little is known about the long-term associations of Ca intake with obesity risk.

OBJECTIVES

We aimed to prospectively examine the association between cumulative Ca intake and the incidence of obesity among American young adults over 30 y of follow-up.

METHODS

Participants were from the CARDIA (Coronary Artery Risk Development in Young Adults) study. A total of 4097 of 5115 black and white individuals aged 18-30 y at baseline in 1985-1986 were included in the current analysis. Dietary and supplemental Ca intake was assessed by the validated interview-based CARDIA diet history at baseline and exam years 7 and 20. Incident cases of obesity were identified when BMI was ≥30 kg/m2 for the first time since baseline. A survival analysis was performed using Cox proportional hazards regression models to estimate the HRs and corresponding 95% CIs for obesity incidence during follow-up.

RESULTS

During a 30-y follow-up (mean ± SD: 20 ± 10 y), 1675 participants developed obesity. Cumulative total Ca intake (dietary plus supplemental Ca) was inversely associated with incidence of obesity in multivariable-adjusted analysis [quintile (Q)5 (highest intake) compared with Q1 (lowest intake): HR: 0.68; 95% CI: 0.56, 0.82; P-trend < 0.01]. This inverse association persisted among Ca supplement users (Q5 compared with Q1: HR: 0.53; 95% CI: 0.40, 0.70; P-trend < 0.01), but was not seen among nonusers.

CONCLUSIONS

Following a cohort of Americans from young adulthood to midlife, an inverse association between calcium intake and obesity incidence was observed. Further studies are needed to confirm our findings.

Extra-skeletal effects of dietary calcium: Impact on the cardiovascular system, obesity, and cancer

Calcium is well known to be integral to bone and muscle health, with deleterious effects such as osteoporosis associated with inadequate calcium intake. Recent studies have also highlighted the significant effects of calcium in extra-musculoskeletal functioning, including the cardiovascular system, obesity, and cancer. Calcium impacts the cardiovascular system as an antagonist associated with a reduction in hypertension, increase vasodilation, and improvement in blood vessel function when obtained in the diet as an organic source, through food. However, the inorganic source of calcium, found in supplements, may be negatively associated with the cardiovascular system due to plaque deposits and atherogenesis when taken in excess. Some studies suggest that calcium intake may impact obesity by regulation of adipogenesis and reducing fat deposits with resulting weight loss. The pathogenesis of calcium for reducing obesity is thought to be related in part to its impact on gut microbiota profile, with the suggestion that calcium may have prebiotic properties. Animal and some human studies propose that calcium may also have a role in cancer prevention and/or treatment due to its function in the cell proliferation process and the impact on hormonal regulation, and thus warrants more investigations in the human population. Some prospective and small clinical studies suggest that calcium may be beneficial for colorectal cancer. Overall, emerging research in various areas continues to highlight the essentiality of dietary calcium for functioning at the molecular and biochemical level toward improvement in health and some chronic disease conditions.

Meta-analysis of randomized controlled trials on calcium supplements and dairy products for changes in body weight and obesity indices

This meta-analysis was performed to investigate whether calcium supplements and dairy products change obesity indices including fat mass. Original articles published in English between July 2009 and August 2019 were identified. Ten and 14 randomised controlled trials (RCTs) with ≥ 12 weeks interventions of calcium supplements and dairy products among overweight or obese adults aged ≥18 were critically reviewed. Mean difference (MD) or standardised mean difference (SMD) with 95% confidence interval (CI) were obtained using a random effect meta-analysis. Dairy products significantly changed fat mass (SMD, 95% CI; -0.40 [-0.77, -0.02]) and BMI (MD, 95% CI: -0.46 kg/m2 [-0.67, -0.26]), and calcium supplements also showed changes in fat mass (SMD, 95% CI; -0.15[-0.28, -0.02]). However, in the analysis of RCTs with low risk of bias scores, the significant changes remained only in the dairy-products intervention. Our findings suggest that dairy products without distinction of fat percentage may help reduce fat mass and BMI, but calcium supplements may not.

Effect of dairy intake with or without energy restriction on body composition of adults: overview of systematic reviews and meta-analyses of randomized controlled trials

CONTEXT

Some studies suggest that consumption of dairy products can aid in weight loss, while others suggest a negative effect or no effect.

OBJECTIVE

An overview of systematic reviews and meta-analyses was conducted to examine the effect of dairy product consumption on changes in body composition.

DATA SOURCES

PRISMA guidelines were followed to ensure transparent reporting of evidence. The MEDLINE, Embase, Cochrane Central Database of Systematic Reviews, and Web of Science databases were searched from inception to April 2018.

STUDY SELECTION

Six systematic reviews and 47 associated meta-analyses (which included the results of 58 different randomized controlled trials) published in English or Spanish and reporting data on dairy intake and changes in weight, fat mass, lean mass, or waist circumference were included.

DATA EXTRACTION

Two authors independently extracted the data and assessed the risk of bias using the AMSTAR2 tool.

RESULTS

Dairy consumption interventions without dietary energy restriction had no significant effects on weight, fat mass, lean mass, or waist circumference. Interventions in energy-restricted settings had significant effects on fat mass and body weight.

CONCLUSIONS

Increasing total dairy intake without energy restriction in adults does not affect body composition. In the context of an energy-restricted diet, however, increased dairy intake results in lower fat mass and body weight but has no conclusive effects on waist circumference or lean mass.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration number CRD42018094672.

Associations of types of dairy consumption with adiposity: cross-sectional findings from over 12 000 adults in the Fenland Study, UK

Evidence from randomised controlled trials supports beneficial effects of total dairy products on body weight, fat and lean mass, but evidence on associations of dairy types with distributions of body fat and lean mass is limited. We aimed to investigate associations of total and different types of dairy products with markers of adiposity, and body fat and lean mass distribution. We evaluated cross-sectional data from 12 065 adults aged 30-65 years recruited to the Fenland Study between 2005 and 2015 in Cambridgeshire, UK. Diet was assessed with an FFQ. We estimated regression coefficients (or percentage differences) and their 95 % CI using multiple linear regression models. The medians of milk, yogurt and cheese consumption were 293 (interquartile range (IQR) 146-439), 35·3 (IQR 8·8-71·8) and 14·6 (IQR 4·8-26·9) g/d, respectively. Low-fat dairy consumption was inversely associated with visceral:subcutaneous fat ratio estimated with dual-energy X-ray absorptiometry (-2·58 % (95 % CI -3·91, -1·23 %) per serving/d). Habitual consumption per serving/d (200 g) of milk was associated with 0·33 (95 % CI 0·19, 0·46) kg higher lean mass. Other associations were not significant after false discovery correction. Our findings suggest that the influence of milk consumption on lean mass and of low-fat dairy consumption on fat mass distribution may be potential pathways for the link between dairy consumption and metabolic risk. Our cross-sectional findings warrant further research in prospective and experimental studies in diverse populations.

Nutrient-rich, high-quality, protein-containing dairy foods in combination with exercise in aging persons to mitigate sarcopenia

Sarcopenic declines in muscle mass and function contribute to the risk of falls, reduced mobility, and progression to frailty in older persons. Mitigation of sarcopenia can be achieved by consumption of higher quality protein in sufficient quantities, which current research suggests are greater than the recommended intakes of approximately 0.8 g/kg bodyweight/d. In addition, higher levels of physical activity and participation in exercise to support cardiovascular fitness and musculoskeletal function work additively with protein in attenuating sarcopenia. This narrative review provides evidence to support a recommendation for per-meal protein targets in older persons that are underpinned by knowledge of muscle protein turnover. Based on work examining acute dose-responses of muscle protein synthesis (MPS) to protein, a proposed per-meal target for protein intakes is set at approximately 0.4-0.6 g protein/kg bodyweight/meal for older persons. Habitual patterns of dietary protein intake tend to emphasize a skewed protein distribution, which would not maximize muscle anabolism. Observational studies show that more even patterns of protein intake are associated with increased muscle mass and improved muscle function. A food-based approach to achieving these protein targets would be advantageous, and the nutrient density of the protein-containing foods would be particularly important for older persons. Dairy foods provide high-quality protein and contain several nutrients of concern for older persons. This brief review provides an overview of the science underpinning why dairy foods should be a point of nutritional emphasis for older persons. Practical suggestions are provided for implementation of dairy foods into dietary patterns to meet the protein and other nutrient targets for older persons.

Science dialogue mapping of knowledge and knowledge gaps related to the effects of dairy intake on human cardiovascular health and disease

Dairy has been described as everything from a superfood to a poison; yet, arguments, assumptions, and data justifying these labels are not always clear. We used an issue-based information system, "dialogue mapping™," to summarize scientific points of a live panel discussion on the putative effects of dairy on cardiovascular diseases (CVD) from a day-long session among experts in nutrition and CVD. Dialogue mapping captures relations among ideas to explicitly, logically, and visually connect issues/questions, ideas, pro/con arguments, and agreements, even if discussed at different times. Experts discussed two propositions: for CVD risk, consumption of full-fat dairy products 1) should be minimized, in part because of their saturated fat content, or 2) need not be minimized, despite their saturated fat content. The panel discussed the dairy-CVD relation through blood lipids, diabetes, obesity, energy balance, blood pressure, dairy bioactives, biobehavioral components, and other putative causal pathways. Associations and effects reported in the literature have varied by fat content of dairy elements considered, study design, intake methods, and biomarker versus disease outcomes. Two conceptual topics emerged from the discussion: 1) individual variability: whether recommendations should be targeted only to those at high CVD risk; 2) quality of evidence: whether data on dairy-CVD relations are strong enough for reliable conclusions-positive, negative, or null. Future procedural improvements for science dialog mapping include using singular rather than competing propositions for discussion.

Association between dietary diversity and obesity in Ardebil adults: a case-control study

Purpose

Obesity is a multi-factorial problem that develops from an interaction between diet, genetics, physical activity, medication, and other factors. This paper aims to examine the association between dietary diversity score (DDS) and obesity among adults of Ardebil.

Design/methodology/approach

This case-control study was conducted on 204 cases (obese and overweight participants) and 204 controls (healthy weight individuals) matched by socioeconomic status (SES), age (older than 30 years) and sex. Dietary intake was assessed using a 24 h food recall questionnaire. Data on physical activity and socio-demographic variables were gathered. DDS was computed based on the scoring of the 14 food groups recommended by the Food and Agriculture organization guideline.

Findings

The DDS of the obese group was higher (5.02 ± 1.02) than that of the healthy weight group (4.23 ± 1.18) (p < 0.001). There was a significant association between DDS and body mass index (BMI) in both groups of study, but this association was more significant in the obese group (β= 0.501,p = 0.021) than that of healthy weight group (β= 0.413,p= 0.042). Vegetable food group score in both groups of the study was associated with obesity inversely (p < 0.05).

Originality/value

This study was conducted for the first time in Ardabil city and the results showed for the first time that there is a relationship between dietary diversity and obesity. People with a higher dietary diversity score are more likely to be obese. In fact, this study for the first time proved that people who are obese have a more varied diet but less vegetables and fruits.

Effects of Full-Fat and Fermented Dairy Products on Cardiometabolic Disease: Food Is More Than the Sum of Its Parts

Current dietary recommendations to limit consumption of saturated fat are largely based on early nutrition studies demonstrating a direct link between dietary saturated fat, elevated blood cholesterol levels, and increased risk of cardiovascular disease. As full-fat dairy products are rich in saturated fat, these dietary guidelines recommend consumption of fat-free or low-fat dairy products in place of full-fat dairy. However, dairy products vary greatly in both their nutrient content and their bioactive ingredients, and research increasingly highlights the importance of focusing on whole foods (i.e., the food matrix) as opposed to single nutrients, such as saturated fat. In fact, the weight of evidence from recent large and well-controlled studies, systematic reviews, and meta-analyses of both observational studies and randomized controlled trials indicates that full-fat dairy products, particularly yogurt and cheese, do not exert the detrimental effects on insulin sensitivity, blood lipid profile, and blood pressure as previously predicted on the basis of their sodium and saturated fat contents; they do not increase cardiometabolic disease risk and may in fact protect against cardiovascular disease and type 2 diabetes. Although more research is warranted to adjust for possible confounding factors and to better understand the mechanisms of action of dairy products on health outcomes, it becomes increasingly clear that the recommendation to restrict dietary saturated fat to reduce risk of cardiometabolic disease is getting outdated. Therefore, the suggestion to restrict or eliminate full-fat dairy from the diet may not be the optimal strategy for reducing cardiometabolic disease risk and should be re-evaluated in light of recent evidence.

Dietary Approaches to Stop Hypertension (DASH): potential mechanisms of action against risk factors of the metabolic syndrome

The metabolic syndrome is a cluster of disorders dominated by abdominal obesity, hypertriacylglycerolaemia, low HDL-cholesterol, high blood pressure and high fasting glucose. Diet modification is a safe and effective way to treat the metabolic syndrome. Dietary Approaches to Stop Hypertension (DASH) is a dietary pattern rich in fruits, vegetables and low-fat dairy products, and low in meats and sweets. DASH provides good amounts of fibre, K, Ca and Mg, and limited quantities of total fat, saturated fat, cholesterol and Na. Although DASH was initially designed for the prevention or control of hypertension, using a DASH diet has other metabolic benefits. In the present review, the effect of each dietary component of DASH on the risk factors of the metabolic syndrome is discussed. Due to limited fat and high fibre and Ca content, individuals on the DASH diet are less prone to overweight and obesity and possess lower concentrations of total and LDL-cholesterol although changes in TAG and HDL-cholesterol have been less significant and available evidence in this regard is still inconclusive. Moreover, high amounts of fruit and vegetables in DASH provide great quantities of K, Mg and fibre, all of which have been shown to reduce blood pressure. K, Mg, fibre and antioxidants have also been effective in correcting glucose and insulin abnormalities. Evidence is provided from cross-sectional investigations, cohort studies and randomised controlled trials, and, where available, from published meta-analyses. Mechanisms are described according to human studies and, in the case of a lack of evidence, from animal and cell culture investigations.

Anti-Obesity Effects of Dietary Calcium: The Evidence and Possible Mechanisms

Obesity is a serious health challenge worldwide and is associated with various comorbidities, including dyslipidemia, type 2 diabetes, and cardiovascular disease. Developing effective strategies to prevent obesity is therefore of paramount importance. One potential strategy to reduce obesity is to consume calcium, which has been implicated to be involved in reducing body weight/fat. In this review, we compile the evidence for the anti-obesity roles of calcium in cells, animals, and humans. In addition, we summarize the possible anti-obesity mechanisms of calcium, including regulation of (a) adipogenesis, (b) fat metabolism, (c) adipocyte (precursor) proliferation and apoptosis, (d) thermogenesis, (e) fat absorption and excretion, and (f) gut microbiota. Although the exact anti-obesity roles of calcium in different subjects and how calcium induces the proposed anti-obesity mechanisms need to be further investigated, the current evidence demonstrates the anti-obesity effects of calcium and suggests the potential application of dietary calcium for prevention of obesity.

Dairy Intake and Body Composition and Cardiometabolic Traits among Adults: Mendelian Randomization Analysis of 182041 Individuals from 18 Studies

BACKGROUND

Associations between dairy intake and body composition and cardiometabolic traits have been inconsistently observed in epidemiological studies, and the causal relationship remains ill-defined.

METHODS

We performed Mendelian randomization analysis using an established genetic variant located upstream of the lactase gene (LCT-13910 C/T, rs4988235) associated with dairy intake as an instrumental variable (IV). The causal effects of dairy intake on body composition and cardiometabolic traits (lipids, glycemic traits, and inflammatory factors) were quantified by IV estimators among 182041 participants from 18 studies.

RESULTS

Each 1 serving/day higher dairy intake was associated with higher lean mass [β (SE) = 0.117 kg (0.035); P = 0.001], higher hemoglobin A1c [0.009% (0.002); P < 0.001], lower LDL [-0.014 mmol/L (0.006); P = 0.013], total cholesterol (TC) [-0.012 mmol/L (0.005); P = 0.023], and non-HDL [-0.012 mmol/L (0.005); P = 0.028]. The LCT-13910 C/T CT + TT genotype was associated with 0.214 more dairy servings/day (SE = 0.047; P < 0.001), 0.284 cm higher waist circumference (SE = 0.118; P = 0.017), 0.112 kg higher lean mass (SE = 0.027; P = 3.8 × 10-5), 0.032 mmol/L lower LDL (SE = 0.009; P = 0.001), and 0.032 mmol/L lower TC (SE = 0.010; P = 0.001). Genetically higher dairy intake was associated with increased lean mass [0.523 kg per serving/day (0.170); P = 0.002] after correction for multiple testing (0.05/18). However, we find that genetically higher dairy intake was not associated with lipids and glycemic traits.

CONCLUSIONS

The present study provides evidence to support a potential causal effect of higher dairy intake on increased lean mass among adults. Our findings suggest that the observational associations of dairy intake with lipids and glycemic traits may be the result of confounding.

Dietary calcium intake and adiposity in children and adolescents: Cross-sectional and longitudinal results from IDEFICS/I.Family cohort

BACKGROUND AND AIMS

Studies in children and adolescents suggest that higher dairy consumption may exert a protective effect on adiposity. However, only few studies examined the association between dietary calcium intake and body mass measures with conflicting results. We evaluated the association between total dietary calcium, calcium from dairy and non-dairy sources and anthropometric indices in a large European cohort of children and adolescents.

METHODS AND RESULTS

As many as 6,696 children belonging to the IDEFICS study were eligible for the cross-sectional analysis (Boys = 51%; age 6.0 ± 1.8 years; mean ± SD). Of these, 2,744 were re-examined six years later (Boys = 49.6%; age = 11.7 ± 1.8 years) in the framework of the I.Family study. The exposures were the baseline energy-adjusted total, dairy and non-dairy calcium intakes measured by a validated 24-h dietary recall. Multivariable linear regression was used to determine the association between calcium intake and z-scores of anthropometric indices (body mass index, BMI; waist circumference, WC; sum of skinfolds, SS; fat mass index, FMI) at baseline, and their variation over the 6 years follow-up. The association of dietary calcium with the incidence of overweight/obesity was also assessed. At baseline, an inverse association between total calcium intake and all the adiposity indices was consistently observed in boys, while only SS and FMI were significant in girls. The prevalence of overweight/obesity decreased significantly (P < 0.0001) across tertiles of calcium intake, in both sexes. Over the follow-up, boys with higher baseline calcium intake value showed significantly lower increase in BMI, WC and FMI z-scores, while in girls only a lower increase in WC z-score was observed. Only in boys, the risk to become overweight/obese decreased significantly across tertiles of calcium intake. Similar results were observed by analyzing only dietary calcium from dairy, while no association was observed between non-dairy calcium and adiposity indices.

CONCLUSIONS

We showed in a large cohort of European children and adolescents that dietary calcium intake may play a role in the modulation of body fat in developmental age. The association between dietary calcium and adiposity indices was driven by dairy calcium, while no effect was observed for non-dairy calcium intake. The existence of a sex-related difference in the association deserves further investigations.

Nutritionist and obesity: brief overview on efficacy, safety, and drug interactions of the main weight-loss dietary supplements

Over the past 20 years the use of dietary supplements as adjuvant therapy for weight loss gained growing favor among consumers and dietician-nutritionists, with the subsequent astounding increase in health costs. Despite the reassuring label of natural remedy for losing weight, dietary supplements contain a wide variety of ingredients on which available information is rather scanty and scientifically incomplete. Currently, there is little evidence that weight-loss supplements offer effective aids to reduce weight and meet criteria for recommended use. Robust, randomized, placebo-controlled studies to provide clear-cut scientific evidence of their efficacy and potential side effects in clinical practice are still lacking. Understanding the evidence for the efficacy, safety, and quality of these supplements among nutritionists and physicians is critical to counsel patients appropriately, especially considering the risk of serious adverse effects and interference with concomitant therapies. Detailed information on the efficacy and safety of the most commonly used weight-loss dietary supplements has been recently published by the National Institutes of Health (NIH). However, in this report the thorny issue that may result from drug interactions with weight-loss dietary supplements has been not sufficiently addressed. The aim of this review was to provide a synthetic, evidence-based report on efficacy and safety of the most commonly used ingredients in dietary supplements marketed for weight loss, particularly focusing on their possible drug interactions.

Effects of Dairy Products Consumption on Body Weight and Body Composition Among Adults: An Updated Meta-Analysis of 37 Randomized Control Trials

SCOPE

Effects of dairy consumption on body weight and body composition have been inconsistently observed in randomized control trials (RCTs). Our meta-analysis aims to systematically evaluate the effects of dairy consumption on body weight and body composition among the adults.

METHODS AND RESULTS

We conducted a comprehensive search of the Cochrane Library, PubMed, and Embase databases of the relevant studies from 1966 to Mar 2017 regarding dairy consumption on body weight and body composition including body fat, lean mass, and waist circumference (WC). The summary results are pooled by using a random-effects meta-analysis. Thirty-seven RCTs with 184 802 participants are included in this meta-analysis. High dairy intervention increased body weight (0.01, 95% CI: -0.25, 0.26, I² = 78.3%) and lean mass (0.37, 95% CI: 0.11, 0.62, I² = 83.4%); decreased body fat (-0.23, 95% CI: -0.48, 0.02, I² = 78.2%) and WC (-1.37, 95% CI: -2.28, -0.46, I² = 98.9%) overall. In the subgroup analysis, we found that consumption of dairy products increases body weight (0.36, 95% CI: 0.01, 0.70, I² = 83.1%) among participants without energy restriction. Dairy consumption decreases body weight (-0.64, 95% CI: -1.05, -0.24, I² = 60.2%), body fat (-0.56, 95%CI: -0.95, -0.17, I² = 66.6%), and waist circumference (-2.18, 95%CI: -4.30, -0.06, I² = 99.0%) among the adults with energy restriction.

CONCLUSIONS

This meta-analysis suggests a beneficial effect of energy-restricted dairy consumption on body weight and body composition. However, high dairy consumption in the absence of caloric restriction may increase body weight.

Abnormality in Maternal Dietary Calcium Intake During Pregnancy and Lactation Promotes Body Weight Gain by Affecting the Gut Microbiota in Mouse Offspring

SCOPE

To investigate the effects of calcium status in early life on adult body weight and the underlying mechanisms involved in gut microbiota and related lipid metabolism.

METHODS AND RESULTS

Three to four-week-old C57BL/6J female mice were fed diets with normal, insufficient, and excessive calcium respectively throughout pregnancy and lactation. The weaning male pups were fed with a high-fat diet for 16 weeks, with a normal-fat diet to the normal calcium group as control. The offspring fecal microbiota was analyzed by 16S rRNA high-throughput sequencing, and mRNA expressions of genes were determined by the real-time RT-PCR. Maternal insufficient or excessive calcium intake exacerbated offspring obesity, with expressional changes in the Fasn, Acc1, LPL, Fiaf, and PPAR-α genes in the liver or fat. The dysbiosis in gut microbiota in obese offspring was exacerbated by maternal imbalanced calcium intake, with increased Firmicutes and decreased Bacteroidetes in calcium insufficiency, and decreased Verrucomicrobia in calcium excess. Several genera, including Bacteroides, were reduced, and Lachnospiraceae and Lactobacillus were increased by maternal insufficient or excessive calcium intake.

CONCLUSION

Imbalance in maternal calcium intake promotes body weight gain in offspring, which may be mediated by calcium's modulation on the gut microbiota and lipid metabolism.

Influence of Calcium and Vitamin D Intakes on Body Composition in Children and Adolescents

Identifying nutritional strategies to maintain a healthy body weight and reduce the comorbidities associated with obesity is extremely important. We aimed to investigate whether calcium and vitamin D intakes are associated with body composition measurements in a population of children and adolescents. A cross-sectional study was conducted involving 1,060 children and adolescents (65.8% females; 34.2% males) aged 9 to 19 years. Fat mass, percentage of fat mass, and fat-free mass were measured using a body composition analyzer (TANITA BC-418MA®). The mean dietary calcium and vitamin intakes were 829.66 ± 328.34 mg/day and 200.78 ± 400.91 IU/day. Linear regression analysis revealed a lack of significant association between daily calcium and vitamin D intakes and body composition measurements, after adjusting the model for age, sex, maturation status, and energy intake. Dietary calcium and vitamin D intakes do not appear to be associated with higher adiposity measurements in children and adolescents.

Perspective: Total, Added, or Free? What Kind of Sugars Should We Be Talking About?

There is consistent public guidance to limit sugars intakes. However, WHO recommendations are for "free" sugars, whereas some other guidance documents and public discussion focus on "added" sugars, and globally most food labeling states "total" sugars. Total sugars comprise all mono- and disaccharides, regardless of source, whereas both added and free sugars exclude the sugars that naturally occur in dairy products and intact fruit and vegetables. Definitions of added and free sugars differ mainly in their respective exclusion or inclusion of sugars in juiced or pureed fruit and vegetables. To date, there has been little evidence-based analysis of the scientific basis for these different sugar classifications or implications of their adoption for consumer communication and nutrition labeling. Evidence of discriminating relations of total compared with added or free sugars with weight gain or energy intake, type 2 diabetes, and dental caries was identified from recent systematic reviews and meta-analyses. The relations were weakest for total sugars and most consistent for dietary sources corresponding to free sugars (including sugars added to and in fruit juices). Consideration of these health outcomes suggests that the emphasis for intake monitoring, public health guidance, and consumer communication should be on free sugars. However, at present, the adoption of free sugars for these purposes would also carry challenges related to implementation, including consumer understanding, consensus on specifications, and current (labeling) regulations.

Milk and other dairy foods and risk of hip fracture in men and women

The role of dairy foods for hip fracture prevention remains controversial. In this study, among US men and women, a glass of milk per day was associated with an 8% lower risk of hip fracture. This contrasts with a reported increased risk with higher milk intake in Swedish women.

INTRODUCTION

The purpose of this study was to examine whether higher milk and dairy food consumption are associated with risk of hip fracture in older adults following a report of an increased risk for milk in Swedish women.

METHODS

In two US cohorts, 80,600 postmenopausal women and 43,306 men over 50 years of age were followed for up to 32 years. Cox proportional hazards models were used to calculate the relative risks (RR) of hip fracture per daily serving of milk (240 mL) and other dairy foods that were assessed every 4 years, controlling for other dietary intakes, BMI, height, smoking, activity, medications, and disease diagnoses.

RESULTS

Two thousand one hundred thirty-eight incident hip fractures were identified in women and 694 in men. Each serving of milk per day was associated with a significant 8% lower risk of hip fracture in men and women combined (RR = 0.92, 95% confidence interval (CI) 0.87 to 0.97). A suggestive inverse association was found for cheese in women only (RR = 0.91, CI 0.81 to 1.02). Yogurt consumption was low and not associated with risk. Total dairy food intake, of which milk contributed about half, was associated with a significant 6% lower risk of hip fracture per daily serving in men and women (RR = 0.94, CI 0.90 to 0.98). Calcium, vitamin D, and protein from non-dairy sources did not modify the association between milk and hip fracture, nor was it explained by contributions of these nutrients from milk.

CONCLUSIONS

In this group of older US adults, higher milk consumption was associated with a lower risk of hip fracture.

Flavonoids, Dairy Foods, and Cardiovascular and Metabolic Health: A Review of Emerging Biologic Pathways

A growing body of nutritional science highlights the complex mechanisms and pleiotropic pathways of cardiometabolic effects of different foods. Among these, some of the most exciting advances are occurring in the area of flavonoids, bioactive phytochemicals found in plant foods; and in the area of dairy, including milk, yogurt, and cheese. Many of the relevant ingredients and mechanistic pathways are now being clarified, shedding new light on both the ingredients and the pathways for how diet influences health and well-being. Flavonoids, for example, have effects on skeletal muscle, adipocytes, liver, and pancreas, and myocardial, renal, and immune cells, for instance, related to 5'-monophosphate-activated protein kinase phosphorylation, endothelial NO synthase activation, and suppression of NF-κB (nuclear factor-κB) and TLR4 (toll-like receptor 4). Effects of dairy are similarly complex and may be mediated by specific amino acids, medium-chain and odd-chain saturated fats, unsaturated fats, branched-chain fats, natural trans fats, probiotics, vitamin K1/K2, and calcium, as well as by processing such as fermentation and homogenization. These characteristics of dairy foods influence diverse pathways including related to mammalian target of rapamycin, silent information regulator transcript-1, angiotensin-converting enzyme, peroxisome proliferator-activated receptors, osteocalcin, matrix glutamate protein, hepatic de novo lipogenesis, hepatic and adipose fatty acid oxidation and inflammation, and gut microbiome interactions such as intestinal integrity and endotoxemia. The complexity of these emerging pathways and corresponding biological responses highlights the rapid advances in nutritional science and the continued need to generate robust empirical evidence on the mechanistic and clinical effects of specific foods.

Dairy-Related Dietary Patterns, Dietary Calcium, Body Weight and Composition: A Study of Obesity in Polish Mothers and Daughters, the MODAF Project

The role of the family environment in regards to dairy products and dietary calcium in the context of obesity is not fully understood. The aim of the study was to investigate the association among dairy-related dietary patterns (DDPs), dietary calcium, body weight and composition in mothers and daughters. Data were collected through a cross-sectional survey within the MODAF Project. A total sample of 712 pairs of mothers (<60 years) and daughters (12-21 years) was studied. This study included 691 pairs. A semi-quantitative food frequency questionnaire (ADOS-Ca) was used to collect dietary data. Waist circumference (WC), body fat, waist-to-height ratio (WHtR) and body mass index (BMI) were determined. Previously derived DDPs were used-three in mothers and three in daughters. In mothers, two of the DDPs were characterized by higher consumption of various dairy products with suboptimal calcium content (means: 703 or 796 mg/day) which decreased the chance of: z-WC > 1 standard deviation (SD), WC > 80 cm, body fat > 32%, WHtR > 0.5, BMI = 25-29.9 kg/m² or BMI ≥ 30 kg/m² by 44-67% when compared to low-dairy low-calcium DDP (288 mg/day). In mothers per 100 mg/day of dietary calcium, the chance of z-WC > 1SD, WC > 80 cm, z-WHtR > 1SD, WHtR > 0.5 cm, BMI = 25 to 29.9 kg/m² or BMI ≥ 30 kg/m² decreased by 5-9%. In correspondence analysis, a clear association was found between mothers' and daughters' low-dairy low-calcium DDPs and upper categories of z-WC (>1 SDs). This study reinforces evidence of the similarity between mothers and daughters in dairy-related dietary patterns and provides a new insight on the adverse relation between low-dairy low-calcium dietary patterns and obesity. It was found that diets containing various dairy products with suboptimal dietary calcium content may be recommended in obesity prevention.

Dairy Consumption and Body Mass Index Among Adults: Mendelian Randomization Analysis of 184802 Individuals from 25 Studies

BACKGROUND

Associations between dairy intake and body mass index (BMI) have been inconsistently observed in epidemiological studies, and the causal relationship remains ill defined.

METHODS

We performed Mendelian randomization (MR) analysis using an established dairy intake-associated genetic polymorphism located upstream of the lactase gene (LCT-13910 C/T, rs4988235) as an instrumental variable (IV). Linear regression models were fitted to analyze associations between (a) dairy intake and BMI, (b) rs4988235 and dairy intake, and (c) rs4988235 and BMI in each study. The causal effect of dairy intake on BMI was quantified by IV estimators among 184802 participants from 25 studies.

RESULTS

Higher dairy intake was associated with higher BMI (β = 0.03 kg/m² per serving/day; 95% CI, 0.00-0.06; P = 0.04), whereas the LCT genotype with 1 or 2 T allele was significantly associated with 0.20 (95% CI, 0.14-0.25) serving/day higher dairy intake (P = 3.15 × 10^-12) and 0.12 (95% CI, 0.06-0.17) kg/m² higher BMI (P = 2.11 × 10^-5). MR analysis showed that the genetically determined higher dairy intake was significantly associated with higher BMI (β = 0.60 kg/m² per serving/day; 95% CI, 0.27-0.92; P = 3.0 × 10^-4).

CONCLUSIONS

The present study provides strong evidence to support a causal effect of higher dairy intake on increased BMI among adults.

Assessing the evidence for weight loss strategies in people with and without type 2 diabetes

This review will examine topical issues in weight loss and weight maintenance in people with and without diabetes. A high protein, low glycemic index diet would appear to be best for 12-mo weight maintenance in people without type 2 diabetes. This dietary pattern is currently being explored in a large prevention of diabetes intervention. Intermittent energy restriction is useful but no better than daily energy restriction but there needs to be larger and longer term trials performed. There appears to be no evidence that intermittent fasting or intermittent severe energy restriction has a metabolic benefit beyond the weight loss produced and does not spare lean mass compared with daily energy restriction. Meal replacements are useful and can produce weight loss similar to or better than food restriction alone. Very low calorie diets can produce weight loss of 11-16 kg at 12 mo with persistent weight loss of 1-2 kg at 4-6 years with a very wide variation in long term results. Long term medication or meal replacement support can produce more sustained weight loss. In type 2 diabetes very low carbohydrate diets are strongly recommended by some groups but the long term evidence is very limited and no published trial is longer than 12 mo. Although obesity is strongly genetically based the microbiome may play a small role but human evidence is currently very limited.

A Mendelian randomization study of the effect of calcium on coronary artery disease, myocardial infarction and their risk factors

Meta-analyses of randomized controlled trials (RCTs) suggest calcium could have adverse effects on cardiovascular disease, although these findings are controversial. To clarify, we assessed whether people with genetically higher calcium had a higher risk of coronary artery disease (CAD), myocardial infarction (MI) and their risk factors. We used a two-sample Mendelian randomization study. We identified genetic variants (single nucleotide polymorphisms (SNPs)) that independently contributed to serum calcium at genome-wide significance which we applied to large extensively genotyped studies of CAD, MI, diabetes, lipids, glycaemic traits and adiposity to obtain unconfounded estimates, with body mass index (BMI) as a control outcome. Based on 4 SNPs each 1 mg/dl increase in calcium was positively associated with CAD (odds ratio (OR) 1.49, 95% confidence interval (CI) 1.02–2.17), MI (OR 1.58, 95% CI 1.06–2.35), LDL-cholesterol (0.21 standard deviations, 95% CI 0.01–0.4), total cholesterol (0.21 standard deviations, 95% CI 0.03-0.38) and possibly triglycerides (0.19 standard deviations, 95% CI −0.1–0.48), but was unlikely related to BMI although the estimate lacked precision. Sensitivity analysis using 13 SNPs showed a higher risk for CAD (OR 1.87, 95% CI 1.14–3.08). Our findings, largely consistent with the experimental evidence, suggest higher serum calcium may increase the risk of CAD.

Milk and dairy products: good or bad for human health? An assessment of the totality of scientific evidence

Background

There is scepticism about health effects of dairy products in the public, which is reflected in an increasing intake of plant-based drinks, for example, from soy, rice, almond, or oat.

Objective

This review aimed to assess the scientific evidence mainly from meta-analyses of observational studies and randomised controlled trials, on dairy intake and risk of obesity, type 2 diabetes, cardiovascular disease, osteoporosis, cancer, and all-cause mortality.

Results

The most recent evidence suggested that intake of milk and dairy products was associated with reduced risk of childhood obesity. In adults, intake of dairy products was shown to improve body composition and facilitate weight loss during energy restriction. In addition, intake of milk and dairy products was associated with a neutral or reduced risk of type 2 diabetes and a reduced risk of cardiovascular disease, particularly stroke. Furthermore, the evidence suggested a beneficial effect of milk and dairy intake on bone mineral density but no association with risk of bone fracture. Among cancers, milk and dairy intake was inversely associated with colorectal cancer, bladder cancer, gastric cancer, and breast cancer, and not associated with risk of pancreatic cancer, ovarian cancer, or lung cancer, while the evidence for prostate cancer risk was inconsistent. Finally, consumption of milk and dairy products was not associated with all-cause mortality. Calcium-fortified plant-based drinks have been included as an alternative to dairy products in the nutrition recommendations in several countries. However, nutritionally, cow's milk and plant-based drinks are completely different foods, and an evidence-based conclusion on the health value of the plant-based drinks requires more studies in humans.

Conclusion

The totality of available scientific evidence supports that intake of milk and dairy products contribute to meet nutrient recommendations, and may protect against the most prevalent chronic diseases, whereas very few adverse effects have been reported.

Effects of calcium supplementation on body weight: a meta-analysis

BACKGROUND

Whether calcium supplementation can reduce body weight and prevent obesity remains unclear because of inconsistent reports.

OBJECTIVE

We performed a meta-analysis to investigate the correlations between calcium supplementation and changes in body weight on the basis of age, sex, body mass index (BMI) of the subjects, and length of calcium intervention.

DESIGN

PubMed, EMBASE, Web of Knowledge, and China National Knowledge Infrastructure databases were systematically searched to select relevant studies that were published from January 1994 to March 2016. Both randomized controlled trials and longitudinal studies of calcium supplementation were included, and random- or fixed-effects models in a software program were used for the data analysis.

RESULTS

Thirty-three studies involving a total of 4733 participants were included in this meta-analysis. No significant differences in weight changes were shown between calcium intervention and control groups (mean: -0.01 kg; 95% CI -0.02, 0.00 kg; P = 0.12). However, negative correlations between calcium supplementation and weight changes were shown in children and adolescents (mean: -0.26 kg; 95% CI: -0.41, -0.11 kg; P < 0.001) and in adult men and either premenopausal or old (>60 y of age) women (mean: -0.91 kg; 95% CI: -1.38, -0.44 kg; P < 0.001) but not in postmenopausal women (mean: -0.14 kg; 95% CI: -0.54, 0.26 kg; P = 0.50). When BMI was considered, a negative correlation between calcium supplementation and weight changes was observed in subjects with normal BMI (mean: -0.53 kg; 95% CI: -0.89, -0.16 kg; P = 0.005) but not in overweight or obese subjects (mean: -0.35 kg; 95% CI: -0.81, 0.11 kg; P = 0.14). Compared with the control groups, no differences in weight changes were shown in the calcium-intervention groups when the lengths of calcium interventions were <6 mo (mean: -0.09 kg; 95% CI: -0.45, 0.26 kg; P = 0.60) or ≥6 mo (mean: -0.01 kg; 95% CI: -0.02, 0.01 kg; P = 0.46).

CONCLUSION

Increasing calcium intake through calcium supplements can reduce body weight in subjects who have a normal BMI or in children and adolescents, adult men, or premenopausal women.

Consumption of Dairy Products in Relation to Changes in Anthropometric Variables in Adult Populations: A Systematic Review and Meta-Analysis of Cohort Studies

BACKGROUND

The current state of knowledge regarding the association of dairy products and weight gain, overweight, and obesity is based on studies reporting contradicting and inconclusive results. The aim of the present study was thus to clarify the link between dairy consumption in relation to changes in anthropometric measures/adiposity by a meta-analytical approach.

METHODS

For the meta-analysis PubMed, EMBASE, Web of Sciences, and google scholar were searched by two independent authors up to May 2016 with no restriction to language or calendar date. Prospective cohort studies reporting about intake of dairy consumption (including milk, yogurt, cheese, butter) and changes in body weight or waist circumference, risk of overweight, obesity, or weight gain were eligible. Pooled effects were calculated using a random effects model, and also a fixed effect model for sensitivity analysis. Due to the heterogeneity of statistical analytical approaches of the studies the analysis were done separately for beta-coefficients of changes in body weight and/or waist circumference per serving of dairy, for differences in weight gain/gain in waist circumference when comparing extreme categories of dairy consumption, and for odds ratios in regard to weight gain, overweight/obesity, or abdominal obesity.

FINDINGS

24 studies (27 reports) met the inclusion criteria for the systematic review, and 22 studies provided sufficient data for inclusion in the meta-analysis. The meta-analysis of the five studies on changes in body weight per serving of dairy no significant results could be found for whole fat dairy and low fat dairy. However, there was inverse association between changes in body weight for each serving's increase of yogurt (beta: -40.99 gram/year, 95% CI, -48.09 to -33.88), whereas each serving's increase of cheese was positively associated (beta: -10.97 gram/year, 95% CI, 2.86 to 19.07). Furthermore, the highest dairy intake category was associated with a reduced risk of abdominal obesity (OR: 0.85; 95% CI, 0.76 to 0.95), and risk of overweight (OR: 0.87; 95% CI, 0.76 to 1.00) compared to the lowest intake category. No significant association could be observed for risk of weight gain.

CONCLUSION

In summary the results of the meta-analysis still reflect that dairy consumption was not positively related to changes in body weight. Yogurt was the only dairy food that showed some evidence for a beneficial effect, where higher intakes were inversely associated a reduced risk of obesity, changes in body weight or waist circumference. Further research is needed, since the overall interpretation of the results is limited by heterogeneous risk estimates.

Dairy consumption in association with weight change and risk of becoming overweight or obese in middle-aged and older women: a prospective cohort study

BACKGROUND

Studies have reported inconsistent findings on the association between dairy product intake and weight change and obesity. Only a few prospective studies have investigated the role of dairy consumption in both weight change and risk of becoming overweight or obese and whether these associations depend on the initial body weight.

OBJECTIVE

We prospectively investigated how dairy product intake was associated with weight change and risk of becoming overweight or obese in initially normal-weight women.

DESIGN

We studied 18,438 women aged ≥45 y from the Women's Health Study who were free of cardiovascular disease, cancer, and diabetes and had initial body mass index (BMI; in kg/m(2)) from 18.5 to <25 at baseline. Dairy intake was assessed with the use of a 131-item food-frequency questionnaire. Women self-reported body weight along with obesity-related risk factors on baseline and annual follow-up questionnaires. At each follow-up time, women were categorized as normal weight (BMI: 18.5 to <25), overweight (BMI: 25 to <30), or obese (BMI ≥30).

RESULTS

During a mean follow-up of 11.2 y, 8238 women became overweight or obese. Multivariable-adjusted mean ± SD changes in body weight during the follow-up (18 y) were 1.90 ± 0.09, 1.88 ± 0.08, 1.86 ± 0.09, 1.82 ± 0.09, and 1.65 ± 0.09 kg in quintiles 1-5 of total dairy intake, respectively (P-trend = 0.003). Greater intake of high-fat dairy products, but not intake of low-fat dairy products, was associated with less weight gain (P-trend = 0.004). In multivariable-adjusted analyses, lower risk of becoming overweight or obese was observed in the highest quintile of high-fat dairy product intake (HR: 0.92, 95% CI: 0.86, 0.99). Dietary or supplemental calcium or vitamin D was not associated with risk of becoming overweight or obese.

CONCLUSION

Greater consumption of total dairy products may be of importance in the prevention of weight gain in middle-aged and elderly women who are initially normal weight.