No effects of low and high consumption of dairy products and calcium supplements on body composition and serum lipids in Puerto Rican obese adults

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.

Effect of a Short Messaging Service (SMS) intervention delivered to caregivers on energy, nutrients, and food groups intake in infant participants of the WIC program

Objectives

To test the effect of a weekly test message (SMS) intervention for improving feeding practices on infant intake of energy, nutrients, and specific food groups.

Methods

This study was a multi-site, randomized clinical trial, in 202 caregivers of healthy term infants participating in either the Puerto Rico or Hawaii WIC program. Participants were randomized to receive weekly SMS about either infant's general health issues (control) or SMS for improving feeding practices (intervention) to complement WIC messages for 4 months. Anthropometrics and demographics were assessed at baseline. A validated infant food frequency questionnaire was assessed at the four-month visit to assess intake of general food groups. Data was summarized as median (25th and 75th percentiles) or percentage and differences between study arms was compared using Mann Whitney or chi-square.

Results

A total of 163 participants completed the study (n = 84 control and n = 79 intervention). Baseline characteristics were similar between both groups. At 4-6 months of age, compared to the control group, the intervention group had a significantly higher intake of total grains (0.28 oz; 0.00, 0.60; P = 0.033), protein (13.5 g, 10.5, 18.3; P = 0.022), calcium (472 mg; 418, 667; P = 0.012), and zinc (4.39 mg; 2.61, 6.51; P = 0.028). No differences were seen in the other food groups, including breastmilk.

Conclusions for practice

Feeding SMS to complement WIC messages led to higher intakes of some key nutrients but did not have an overall improvement in the intake of food groups. Messaging also did not delay the introduction of complimentary foods or improve breastfeeding rates. Future studies should evaluate the use of more intensive SMS interventions for continued care between WIC visits.

The Impact of Nutrition-Based Interventions on Nutritional Status and Metabolic Health in Small Island Developing States: A Systematic Review and Narrative Synthesis

Small island developing states (SIDS) have a high burden of nutrition-related disease associated with nutrient-poor, energy-dense diets. In response to these issues, we assessed the effectiveness of nutrition-based interventions on nutritional status (under-nutrition) and metabolic health (over-nutrition) among persons in SIDS. We included SIDS-based nutrition studies with change in nutrition status (e.g., markers of anaemia) or metabolic status (e.g., markers of glycaemia) as outcomes. The PRISMA framework was applied and MEDLINE, Embase, CINAHL, OARE library, Web of Science, Scopus, ASSIA, EconLit, AGORA, AGRICOLA, AGRIS, WHO-EMRO, and LILACS were searched (2000−2020). Cochrane risk of bias (ROB) and Cochrane ROBINS-I tools assessed ROB for randomised and non-randomised studies, respectively. PROSPERO registration (CRD42021236396) was undertaken. We included 50 eligible interventions, involving 37,591 participants: 14 trials reported on nutritional status, 36 on metabolic health. Effective interventions, evaluated at the individual level, took a multifaceted approach for metabolic outcomes; while nutrition outcomes utilised supplements. Most intervention types were suitable for issues related to ‘over’ nutrition versus ‘under’ nutrition. Twenty-six studies (nutrition status (six); metabolic health (twenty)) were effective (p < 0.05). With the current rise of nutrition-related public health challenges, there is a need for further development and evaluation of these and related interventions at the population level.

The Role of Milk on Children's Weight Status: An Epidemiological Study among Preadolescents in Greece

Milk consumption contributes greatly to children's diet, playing a pivotal role in the development and structure of bones and the functioning of the musculoskeletal system and the heart. This study investigated the association between the type of milk and childhood overweight/obesity. In the school period 2014-2016, 1728 students aged 10-12 years and their parents participated. The measurement and classification of their weight status were performed through the criteria of the International Obesity Task Force. Among others, the type of milk consumption was recorded. Four categories of the type of milk children consumed were classified (white milk, chocolate milk, both types of milk, and no milk at all). Children consuming only white milk were 33.1% less likely to be overweight/obese in comparison with children who were not consuming milk at all [OR (95% CI): 0.669 (0.516, 0.867), p = 0.002]. The consumption of chocolate milk showed a protective role against childhood overweight/obesity although its association was not consistently significant. This study highlights the significant contribution of milk (and particularly of white milk) consumption to weight management, and thus its promotion should be consistently encouraged. More studies are needed to shed light on the effects of different dairy foods on weight status in childhood.

No adverse effects of dairy products on lipid profile: A systematic review and meta-analysis of randomized controlled clinical trials

BACKGROUND AND AIMS

The current study aimed to review the effects of dairy foods on lipid profile in randomized controlled clinical trials (RCTs).

METHODS

We searched PubMed, Scopus, Embase, and Central. RCTs that assess the effects of dairy foods on lipid profile were included.

RESULTS

The overall effects of dairy foods on lipid profile were non-significant. Dairy foods were associated with a non-significant reduction in triacylglycerol level, and a non-significant increase in total cholesterol, low density lipoprotein cholesterol, and high-density lipoprotein cholesterol level.

CONCLUSION

We conclude that dairy foods doesn't have any unfavorable effects on lipids.

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.

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.

The effect of calcium supplement intake on lipid profile: a systematic review and meta-analysis of randomized controlled clinical trials

Despite the potential role of dietary calcium in fat excretion, the favorable effects of calcium supplements on lipid profile remains inconclusive. The current study aimed to review the effect of calcium supplement intake on lipid profile in randomized controlled clinical trials (RCTs). This systematic review and meta-analysis was conducted in PubMed, Scopus, Embase, and Central. RCTs which assessed the effects of calcium supplementation on lipid profile were included. All outcomes were recorded as continuous variables, and the effect size was measured. We classified studies according to dose of supplement, study duration, and dyslipidemia. Calcium supplement intake was associated with a significant reduction in low density lipoprotein cholesterol (LDL-C) level (WMD:-0.08; 95%CI:-0.16,-0.01)(mmol/l), especially with intakes of at least 1000 mg/day (WMD:-0.13; 95%CI:-0.23,-0.03)(mmol/l), with intakes of at least 12 weeks (WMD:-0.08; 95%CI: -0.16,-0.00)(mmol/l), and in individuals without dyslipidemia (WMD:-0.15; 95%CI:-0.26,-0.04)(mmol/l). Also, in another subgroup analysis, consumption of less than 1000 mg/day calcium supplement caused a significant increase in Total Cholesterol (TC) level (WMD: 0.24; 95%CI: 0.05,0.42) (mmol/l). In other blood lipids or study subgroups we observed no significant effect. We concluded that calcium supplements had a favorable effect on LDL-C level, especially in individuals without dyslipidemia, higher calcium intakes, and longer period of consumption.

Dairy Consumption and Metabolic Health

Milk and dairy foods are naturally rich sources of a wide range of nutrients, and when consumed according to recommended intakes, contribute essential nutrients across all stages of the life cycle. Seminal studies recommendations with respect to intake of saturated fat have been consistent and clear: limit total fat intake to 30% or less of total dietary energy, with a specific recommendation for intake of saturated fat to less than 10% of total dietary energy. However, recent work has re-opened the debate on intake of saturated fat in particular, with suggestions that recommended intakes be considered not at a total fat intake within the diet, but at a food-specific level. A large body of evidence exists examining the impact of dairy consumption on markers of metabolic health, both at a total-dairy-intake level and also at a food-item level, with mixed findings to date. However the evidence suggests that the impact of saturated fat intake on health differs both across food groups and even between foods within the same food group such as dairy. The range of nutrients and bioactive components in milk and dairy foods are found in different levels and are housed within very different food structures. The interaction of the overall food structure and the nutrients describes the concept of the 'food matrix effect' which has been well-documented for dairy foods. Studies show that nutrients from different dairy food sources can have different effects on health and for this reason, they should be considered individually rather than grouped as a single food category in epidemiological research. This narrative review examines the current evidence, mainly from randomised controlled trials and meta-analyses, with respect to dairy, milk, yoghurt and cheese on aspects of metabolic health, and summarises some of the potential mechanisms for these findings.

Strategies for Healthy Eating Promotion and Behavioral Change Perceived as Effective by Nutrition Professionals: A Mixed-Methods Study

Nutrition professionals may recognize ways to improve diet among their clients/patients. This study aimed to survey strategies and foods that nutrition professionals in Puerto Rico perceive as most effective for healthy eating promotion and behavioral change. The study was a cross-sectional online mixed-methods survey conducted among registered members of the College of Nutritionists and Dietitians of Puerto Rico. Using close-ended questions, nutrition professionals identified foods that they considered as easy to include or difficult to control in the diet of their clients/patients, and strategies that may work best for healthy eating. Frequencies of responses were analyzed. Open-ended questions were qualitatively analyzed in NVivo v11. The response rate was 33.2% (n = 414). The foods deemed as easy to include in the diet were root vegetables (66%), fruit (66%), legumes (57%), water (38%), and yogurt/dairy (37%). The foods deemed as more difficult to control were sugary beverages (63%), sweets and desserts (57%), fats and fried foods (56%), salt (50%), and white rice (44%). The strategies for healthy eating deemed effective were personalized orientation (79%), setting short-term goals (61%), making gradual dietary changes (53%), and setting health-oriented (41%), and personal (37%) goals. Emerging themes from qualitative analysis included the intuited key role of nutrition professionals, the need for policy changes, emphasizing prevention, cultural sensitivity, and practical issues. Respondents suggested potential strategies across levels of the socioecological model. In conclusion, healthy eating strategies and foods perceived by nutrition professionals as effective may shape optimal nutritional counseling and population-wide approaches to improve healthy eating in Puerto Rico.

Dairy Consumption and Cardiometabolic Risk Factors in Patients with Type 2 Diabetes and Overweight or Obesity during Intensive Multidisciplinary Weight Management: A Prospective Observational Study

Dairy products are integral parts of healthy diets; however, their association with cardiometabolic (CM) health among patients with type 2 diabetes (T2D) undergoing weight management is debated. We examined the relationship between dairy consumption and CM biomarkers in 45 subjects with T2D and obesity (mean age 56 ± 9 yrs, 40% female) enrolled in a 12-week intensive multidisciplinary weight management (IMWM) program. After the IMWM program (intervention phase), subjects were followed for 12 weeks (maintenance phase). We stratified subjects based on initial average dairy consumption into infrequent (IFR), less-frequent (LFR), and frequent (FR) consumers. Outcomes were assessed at baseline, 12, and 24 weeks. There were no differences between tertiles at baseline except for higher total energy intake among FR compared with IFR. HbA1c changes showed no association with dairy consumption at 12 or 24 weeks. FR Females achieved greater weight loss at 12 weeks compared with IFR peers (-4.5 kg; 95%CI: -5.5, -3.5). There was a trend towards lower HDL-C with increasing dairy consumption during the intervention phase. In subjects with T2D and overweight or obesity, dairy consumption during weight management is not associated with HbA1c changes but with lower HDL-C and with higher magnitude of weight loss among females.

Prospective associations between total, animal, and vegetable calcium intake and metabolic syndrome in adults aged 40 years and older

BACKGROUND & AIMS

Calcium (Ca) consumption may contribute to a decreased risk of developing metabolic syndrome (MetS). However, epidemiologic evidence on the association between Ca intake and MetS is limited. This study aimed to evaluate the association between dietary Ca intake (animal-based Ca and vegetable-based Ca separately, as well as total Ca intake) and the incidence risk of MetS and its components in the Korean Multi-Rural Communities Cohort (MRCohort).

METHODS

A total of 5509 participants who did not have MetS were enrolled. Dietary Ca intake was calculated using a food frequency questionnaire composed of 106 items.

RESULTS

After 18,880 person-years of follow-up, 876 participants had developed de novo MetS. A significant inverse association between dietary total Ca intake and MetS were observed (incidence rate ratio (IRR) = 0.62, 95% confidence interval (CI) = 0.48-0.81, P for trend = 0.002 for the highest quartile of total Ca intake compared with the lowest quartile). Trends for animal Ca (IRR = 0.77, 95% CI = 0.62-0.97, P for trend = 0.039) and vegetable Ca (IRR = 0.54, 95% CI = 0.40-0.73, P for trend <0.001) were similar. The individual components of overall MetS were also inversely related to total, animal, and vegetable Ca. The tendency for an inverse association was more evident in the group with two of any of the metabolic abnormalities of MetS at baseline than in the group with no more than one MetS component.

CONCLUSIONS

Our findings indicate that a relatively high dietary intake of Ca is associated with lower risk of MetS.

The Effects of Dairy Intake on Insulin Resistance: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

The incidence of type 2 diabetes mellitus (DM) has increased in the US over the last several years. The consumption of low-fat dairy foods has been linked with decreasing the risk of DM but studies have yet to show a clear correlation. We conducted a systematic review and meta-analysis of randomized clinical trials (RCTs) evaluating the effects of dairy intake on homeostatic model assessment of insulin resistance (HOMA-IR), waist circumference, and body weight. In MEDLINE and Embase, we identified and reviewed 49 relevant RCTs: 30 had appropriate data format for inclusion in the meta-analysis. Using the Review Manager 5 software, we calculated the pooled standardized mean differences comparing dairy dietary interventions to control for our outcomes of interest. For HOMA-IR (794 individuals), we found a mean difference of −1.21 (95% CI −1.74 to −0.67; p-value < 0.00001; I² = 92%). For waist circumference (1348 individuals), the mean difference was −1.09 cm (95% CI 1.68 to −0.58; p-value < 0.00001; I² = 94%). For body weight (2362 individuals), the dairy intake intervention group weighed 0.42 kg less than control (p-value < 0.00001; I² = 92%). Our findings suggest that dairy intake, especially low-fat dairy products, has a beneficial effect on HOMA-IR, waist circumference, and body weight. This could impact dietary recommendations to reduce DM risk.

Effects of Milk and Milk-Product Consumption on Growth among Children and Adolescents Aged 6-18 Years: A Meta-Analysis of Randomized Controlled Trials

Although studies have suggested that milk and milk-product consumption may influence growth during childhood and puberty, results are inconsistent. This meta-analysis was performed to evaluate the available evidence of randomized controlled trials (RCTs) assessing whether milk and milk-product consumption could affect growth and body composition among children and adolescents aged 6-18 y. PubMed, EMBASE, Web of Science, and The Cochrane Library databases were systematically searched for all RCTs published up to December 2017 that investigated milk and milk-product consumption (≥12 wk) on growth and body composition among participants (aged 6-18 y) without undernourishment or diseases. Study screening and data extraction by 2 reviewers followed established PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The Cochrane Collaboration's tool was used to assess the quality of the trials. Data were pooled using a random-effects model. Seventeen trials with 2844 children and adolescents were included. Milk and milk-product interventions resulted in a greater increase in body weight (0.48 kg; 95% CI: 0.19, 0.76 kg; P  =  0.001), lean mass (0.21 kg; 95% CI: 0.01, 0.41 kg; P  = 0.04), and attenuated gain in percentage body fat (-0.27%; 95% CI: -0.45%, -0.09%; P  = 0.003) compared with control groups. However, there were no significant changes in fat mass, height, or waist circumference in the intervention groups compared with the control groups (P ≥ 0.05). In subgroup analyses, the baseline weight and age, and the duration of intervention were associated with the efficacy of milk and milk-product intake on the change in lean mass, percentage body fat, and waist circumference, respectively (test for subgroup differences: P < 0.05). Children and adolescents aged 6-18 y consuming milk and milk products are more likely to achieve a lean body phenotype. This meta-analysis was registered in the International Prospective Register of Systematic Reviews (PROSPERO) as CRD42018086850.

Dietary calcium affects body composition and lipid metabolism in rats

Calcium (Ca) intakes may affect cardiovascular disease risk by altering body composition (body weight and fat) and serum lipid profile, but results have been inconsistent and the underlying mechanisms are not well understood. The effects of dietary Ca on body composition and lipid metabolism were examined in rats. Male Sprague-Dawley rats were fed high-fat, high-energy diets containing (g/kg) low (0.75Ca, 0.86 ± 0.05; 2Ca, 2.26 ± 0.02), normal (5Ca, 5.55 ± 0.08) or high (10Ca, 11.03 ± 0.17; 20Ca, 21.79 ± 0.15) Ca for 10 weeks. Rats fed the lowest Ca diet (0.75Ca) had lower (p < 0.05) body weight and fat mass compared to other groups. Rats fed the high Ca diets had lower serum total and LDL cholesterol compared to rats fed normal or low Ca. Liver total cholesterol was lower in rats fed high compared to low Ca. In general, liver mRNA expression of genes involved in cholesterol uptake from the circulation (Ldlr), cholesterol synthesis (Hmgcr and Hmgcs1), fatty acid oxidation (Cpt2) and cholesterol esterification (Acat2) were higher in rats fed higher Ca. Apparent digestibility of total trans, saturated, monounsaturated and polyunsaturated fatty acids was lower in rats fed the high compared to the low Ca diets, with the largest effects seen on trans and saturated fatty acids. Fecal excretion of cholesterol and total bile acids was highest in rats fed the highest Ca diet (20Ca). The results suggest little effect of dietary Ca on body composition unless Ca intakes are very low. Decreased bile acid reabsorption and reduced absorption of neutral sterols and saturated and trans fatty acids may contribute to the better serum lipid profile in rats fed higher Ca.

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.

Impact of Dietary Calcium Supplement on Circulating Lipoprotein Concentrations and Atherogenic Indices in Overweight and Obese Individuals: A Systematic Review

Dyslipidemia is the main risk factor for developing cardiovascular disease. There are discrepancies in the effects of calcium supplementation on modulation of lipid status. Therefore, we aimed to summarize the effects of dietary calcium supplement on circulating lipoprotein concentrations and atherogenic indices in overweight and obese individuals. We conducted a systematic literature search from 2000 until July 2016. PubMed, Scopus, Cochran Library, and ISI Web of Science databases were searched for clinical trials written in English. Placebo controlled clinical trials on calcium or calcium with vitamin D supplement in overweight and obese indiciduals were considered. Finally, 11 clinical trials met the criteria and were included. Most studies (n = 9) evaluated Ca/D co-supplementation. Positive effects of calcium supplementation alone or with vitamin D were as follows: serum levels of total cholesterol (TC; n = 1), triglyceride (TG) concentrations (n = 1), serum levels of low-density lipoprotein cholesterol (LDL-C; n = 5) and high-density lipoprotein cholesterol (HDL-C; n = 3). Seven clinical trials reported atherogenic indices and three of them demonstrated beneficial effects of calcium supplementation on at least one atherogenic index. Calcium supplementation may not be helpful to reduce serum levels of TC and TG in overweight and obese individuals. However, it may modulate LDL-C and HDL-C concentration. More studies are warranted to clarify the effects of calcium supplementation on each atherogenic index.

Patterns of dairy food intake, body composition and markers of metabolic health in Ireland: results from the National Adult Nutrition Survey

Background:

Studies examining the association between dairy consumption and metabolic health have shown mixed results. This may be due, in part, to the use of different definitions of dairy, and to single types of dairy foods examined in isolation.

Objective:

The objective of the study was to examine associations between dairy food intake and metabolic health, identify patterns of dairy food consumption and determine whether dairy dietary patterns are associated with outcomes of metabolic health, in a cross-sectional survey.

Design:

A 4-day food diary was used to assess food and beverage consumption, including dairy (defined as milk, cheese, yogurt, cream and butter) in free-living, healthy Irish adults aged 18–90 years (n=1500). Fasting blood samples (n=897) were collected, and anthropometric measurements taken. Differences in metabolic health markers across patterns and tertiles of dairy consumption were tested via analysis of covariance. Patterns of dairy food consumption, of different fat contents, were identified using cluster analysis.

Results:

Higher (total) dairy was associated with lower body mass index, %body fat, waist circumference and waist-to-hip ratio (P<0.001), and lower systolic (P=0.02) and diastolic (P<0.001) blood pressure. Similar trends were observed when milk and yogurt intakes were considered separately. Higher cheese consumption was associated with higher C-peptide (P<0.001). Dietary pattern analysis identified three patterns (clusters) of dairy consumption; 'Whole milk', 'Reduced fat milks and yogurt' and 'Butter and cream'. The 'Reduced fat milks and yogurt' cluster had the highest scores on a Healthy Eating Index, and lower-fat and saturated fat intakes, but greater triglyceride levels (P=0.028) and total cholesterol (P=0.015). conclusion: Overall, these results suggest that while milk and yogurt consumption is associated with a favourable body phenotype, the blood lipid profiles are less favourable when eaten as part of a low-fat high-carbohydrate dietary pattern. More research is needed to better understand this association.

Conclusion:

Overall, these results suggest that although milk and yogurt consumption is associated with a favourable body phenotype, the blood lipid profiles are less favourable when eaten as part of a low-fat high-carbohydrate dietary pattern. More research is needed to better understand this association.

Comprehensive Review of the Impact of Dairy Foods and Dairy Fat on Cardiometabolic Risk

Because regular-fat dairy products are a major source of cholesterol-raising saturated fatty acids (SFAs), current US and Canadian dietary guidelines for cardiovascular health recommend the consumption of low-fat dairy products. Yet, numerous randomized controlled trials (RCTs) have reported rather mixed effects of reduced- and regular-fat dairy consumption on blood lipid concentrations and on many other cardiometabolic disease risk factors, such as blood pressure and inflammation markers. Thus, the focus on low-fat dairy in current dietary guidelines is being challenged, creating confusion within health professional circles and the public. This narrative review provides perspective on the research pertaining to the impact of dairy consumption and dairy fat on traditional and emerging cardiometabolic disease risk factors. This comprehensive assessment of evidence from RCTs suggests that there is no apparent risk of potential harmful effects of dairy consumption, irrespective of the content of dairy fat, on a large array of cardiometabolic variables, including lipid-related risk factors, blood pressure, inflammation, insulin resistance, and vascular function. This suggests that the purported detrimental effects of SFAs on cardiometabolic health may in fact be nullified when they are consumed as part of complex food matrices such as those in cheese and other dairy foods. Thus, the focus on low-fat dairy products in current guidelines apparently is not entirely supported by the existing literature and may need to be revisited on the basis of this evidence. Future studies addressing key research gaps in this area will be extremely informative to better appreciate the impact of dairy food matrices, as well as dairy fat specifically, on cardiometabolic health.

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.

Comparison of the effect of daily consumption of probiotic compared with low-fat conventional yogurt on weight loss in healthy obese women following an energy-restricted diet: a randomized controlled trial

BACKGROUND

Despite evidence for the beneficial effects of probiotics and low-fat dairy products, to our knowledge, no study has compared the beneficial effect on weight loss of consuming a probiotic yogurt (PY) compared with a standard low-fat yogurt (LF) during a hypoenergetic program.

OBJECTIVE

We compared the effect of the PY with LF yogurt consumption on body weight and cardiometabolic risk factors in women during a weight-loss program.

DESIGN

Overweight and obese women [body mass index (in kg/m(2)): 27-40; age: 18-50 y) who usually consumed standard LFs were asked to consume either PY or LF every day with their main meals for 12 wk while following a weight-loss program.

RESULTS

A total of 89 participants were randomly assigned to one of the 2 intervention groups. Baseline variables were not significantly different between groups. A statistically significant reduction in anthropometric measurements and significant improvements in cardiometabolic risk characteristics were observed over the 12 wk in both groups. However, no significant differences in weight loss and anthropometric measurements were seen between groups after the intervention. Compared with the LF group, the PY group had a greater (mean ± SD) decrease in total cholesterol (PY = -0.36 ± 0.10 mmol/L, LF = -0.31 ± 0.10 mmol/L; P = 0.024), low-density lipoprotein cholesterol (PY = -0.35 ± 0.10 mmol/L, LF = -0.31 ± 0.11 mmol/L; P = 0.018), homeostasis model assessment of insulin resistance (PY = -0.55 ± 0.32, LF = -0.42 ± 0.20; P = 0.002), 2-h postprandial glucose (PY = -0.61 ± 0.24 mmol/L, LF = -0.44 ± 0.19 mmol/L; P < 0.001), and fasting insulin concentration (PY = -1.76 ± 1.01 mU/mL, LF = -1.32 ± 0.62 mU/mL; P = 0.002), as secondary endpoints after the study. No significant differences were found for fasting plasma glucose, high-density lipoprotein cholesterol, or triglycerides within both groups after the 12 wk.

CONCLUSION

Consumption of PY compared with LF with main meals showed no significant effects on weight loss. However, it may have positive effects on lipid profiles and insulin sensitivity during a weight-loss program. This trial was registered at http://www.irct.ir/ as IRCT201402177754N8.

Effect of increasing dietary calcium through supplements and dairy food on body weight and body composition: a meta-analysis of randomised controlled trials

This meta-analysis of randomised controlled trials assessed the effect of Ca on body weight and body composition through supplementation or increasing dairy food intake. Forty-one studies met the inclusion criteria (including fifty-one trial arms; thirty-one with dairy foods (n 2091), twenty with Ca supplements (n 2711). Ca intake was approximately 900 mg/d higher in the supplement groups compared with control. In the dairy group, Ca intake was approximately 1300 mg/d. Ca supplementation did not significantly affect body weight (mean change ( - 0·17, 95% CI - 0·70, 0·37) kg) or body fat (mean change ( - 0·19, 95% CI - 0·51, 0·13) kg) compared to control. Similarly, increased dairy food intake did not affect body weight ( - 0·06, 95% CI - 0·54, 0·43) kg or body fat change ( - 0·36, 95% CI - 0·80, 0·09) kg compared to control. Sub-analyses revealed that dairy supplementation resulted in no change in body weight (nineteen studies, n 1010) ( - 0·32, 95% CI - 0·93, 0·30 kg, P= 0·31), but a greater reduction in body fat (thirteen studies, n 564) ( - 0·96, 95% CI - 1·46, - 0·46 kg, P < 0·001) in the presence of energy restriction over a mean of 4 months compared to control. Increasing dietary Ca intake by 900 mg/d as supplements or increasing dairy intake to approximately 3 servings daily (approximately 1300 mg of Ca/d) is not an effective weight reduction strategy in adults. There is, however, an indication that approximately 3 servings of dairy may facilitate fat loss on weight reduction diets in the short term.

Associations between dairy intake and metabolic risk parameters in a healthy French-Canadian population

Observational studies support that dairy product intake is associated with a reduced risk of developing type 2 diabetes; however, several clinical studies report conflicting results on the association between dairy product consumption and metabolic parameters. The aim of this study was to determine associations between dairy product consumption and metabolic profile. Dietary data, using a validated food frequency questionnaire, and fasting blood samples were collected from 233 French Canadians. Plasma phospholipid (PL) fatty acids (FA) concentrations were determined by gas chromatography. Subjects consumed 2.5 ± 1.4 portions of dairy products daily, including 1.6 ± 1.3 portions of low-fat (LF) and 0.90 ± 0.70 portions of high-fat (HF) dairy products. Trans-palmitoleic acid level in plasma PL was related to HF dairy consumption (r = 0.15; p = 0.04). Total (r = –0.21; p = 0.001) and LF dairy (r = –0.20; p = 0.003) intakes were inversely correlated with fasting plasma glucose level. Total dairy intake was inversely associated to systolic blood pressure (r = –0.17; p = 0.008) and diastolic blood pressure (r = –0.14; p = 0.03). LF dairy intake was also inversely correlated with systolic blood pressure (r = –0.17; p = 0.009). Total dairy intake was correlated with plasma C-reactive protein (CRP) (r = 0.15; p = 0.03). No association was found between HF dairy consumption and the risk factors studied. In conclusion, dairy intake is inversely associated with glycaemia and blood pressure; yet, it may modify CRP levels. Moreover, trans-palmitoleic FA levels in plasma PL may be potentially used to assess full-fat dairy consumption.

Participants in an online weight loss program can improve diet quality during weight loss: a randomized controlled trial

Background

Better diet quality has been associated with less weight gain over time. However, few studies have examined the role of diet quality during weight loss. This study aimed to compare changes in diet quality in overweight/obese adults during a weight loss intervention, and determine whether an association between diet quality score and weight loss exists.

Methods

Overweight or obese (BMI 25-40 kg/m²) adults, aged 18–60 years, were recruited from the Hunter Region of NSW, Australia and randomized to one of three groups: a standard online weight loss program (n = 94); an enhanced version of this online program that provided additional personalized feedback and reminders (n = 98); or a wait-list control group (n = 97). Diet quality was calculated using the Australian Recommended Food Score (ARFS) with dietary data from the Australian Eating Survey (AES) Food Frequency Questionnaire at baseline and 12-weeks.

Results

The basic and enhanced groups lost significantly more weight than the control group after 12 weeks (basic -2.2 ± 3.4 kg, enhanced -3.0 ± 4.0 kg, control 0.4 ± 2.4 kg, P < 0.001) with no difference between the basic and enhanced groups. The mean change in ARFS in the enhanced group (2.2 ± 5.7) was significantly higher (P = 0.03) than the control group. There were no significant differences in change in ARFS between the enhanced and basic, or basic and control groups. The ARFS and the fruit, meat, wholegrain, dairy and water sub-scale scores at 12 weeks were significantly associated with greater weight loss (P < 0.05).

Conclusions

Diet quality improved significantly in the enhanced group compared to controls following 12-weeks intervention. Furthermore, higher diet quality was associated with greater weight loss.

Trial Registration

ACTRN12610000197033.

Yeast hydrolysate can reduce body weight and abdominal fat accumulation in obese adults

OBJECTIVE

The aim of this study was to examine the effect of yeast hydrolysate on the abdominal fat in obese humans.

METHODS

We observed the effects of yeast hydrolysate that had a molecular weight below 10 kDa on the anti-abdominal fat accumulation in obese men and women ages 20 to 50 y for 10 wk. The abdominal fat mass was assessed by computed tomographic scans.

RESULTS

By the sixth week, the reductions in energy intake in the yeast group (yeast hydrolysate 1 g/d) were significantly greater than those in the control group (placebo 1 g/d) (P < 0.05). The body weight and body mass index (BMI) were significantly reduced by week 10 compared with baseline in the yeast group, and these differences were significantly greater than those in the control group: body weight 0.83 kg versus -2.60 k g (P < 0.001), BMI 0.29 kg/m(2) versus -0.90 kg/m(2) (P < 0.001). Despite the increased loss of body weight in the yeast group, lean body mass did not significantly differ between the two groups. Body fat mass in the control group did not significantly change between baseline and week 10. However, the yeast group lost a significant amount of body fat mass after 10 wk of treatment (P < 0.01). The differences in abdominal fat thickness and abdominal circumference between the two groups were significant after 10 wk of treatment (P < 0.001). The total abdominal fat area in the yeast group was significantly lower than in the control group after 10 wk of treatment (-7.06 cm(2) versus -17.34 cm(2); P < 0.01).

CONCLUSIONS

Yeast hydrolysate can reduce body weight and the accumulation of abdominal fat without an adverse effect on lean body mass in obese adults, regardless of sex, via the reduction of energy intake.

Effect of dairy calcium from cheese and milk on fecal fat excretion, blood lipids, and appetite in young men

BACKGROUND

Calcium from different dairy sources might affect blood lipids and fecal fat excretion differently because of differences in the food matrix and nutritional composition.

OBJECTIVE

We investigated whether milk- and cheese-based diets with similar calcium contents affect a saturated fatty acid-induced increase in blood lipids differently.

DESIGN

Fifteen healthy, young men participated in a randomized 3 × 2-wk crossover study in which the following 3 isocaloric diets that were similar in fat contents and compositions were compared: control diet [nondairy diet (~500 mg Ca/d)], milk diet [semiskimmed milk-based diet (1700 mg Ca/d)], and cheese diet [semihard cow-cheese-based diet (1700 mg Ca/d)]. Blood was drawn before and after each period, and feces were collected for 5 d during each period.

RESULTS

Saturated fatty acid-induced increases in total and low-density lipoprotein (LDL) cholesterol were lower with the milk diet (mean ± SD: 0.57 ± 0.13 and 0.53 ± 0.11 mmol/L, respectively) (P < 0.01) and cheese diet (0.41 ± 0.15 and 0.47 ± 0.12 mmol/L, respectively) (P < 0.05) than with the control diet (0.89 ± 0.12 and 0.84 ± 0.11 mmol/L, respectively). Fecal fat excretion increased more with the consumption of both the milk (5.2 ± 0.4 g/d) and cheese (5.7 ± 0.4 g/d) diets than with the control diet (3.9 ± 0.3 g/d) (P < 0.001). Changes in blood pressure, high-density lipoprotein cholesterol, triglycerides, and lipid ratios did not differ.

CONCLUSIONS

Compared with the control diet, milk- and cheese-based diets attenuated saturated fatty acid-induced increases in total and LDL cholesterol and resulted in increased fecal fat excretion; however, effects of milk and cheese did not differ. Because the diets contained similar amounts of saturated fat, similar increases in total and LDL cholesterol could be expected; however, both milk and cheese attenuated these responses, which seem to be explained by their calcium contents. This trial was registered at clinicaltrials.gov as NCT01317251.

Dairy products on metabolic health: current research and clinical implications

Dairy products have been thought to have a beneficial role in the metabolic syndrome (MetS). MetS constitutes a cluster of risk factors for an increased mortality, including obesity, impaired glucose homeostasis, hypertension and atherogenic dyslipidemia. Individuals with MetS are also often in a chronic, low-grade inflammatory state. The objective of this review is to examine recent meta-analyses and clinical studies on the association between dairy products consumption and these MetS risk factors. Findings from studies demonstrate that weight loss related to dairy product intake is due to the combination of an energy-restricted diet with consumption of dairy products. Further, a limited number of studies have shown beneficial effects of dairy consumption on plasma lipids, blood pressure, glucose homeostasis or inflammatory and oxidative stress profiles. Overall, this review article suggests that adults should consume at least 2-3 servings of dairy products per day within a well-balanced diet and a healthy lifestyle for metabolic health. Yet, higher dairy product consumption may have additional beneficial effects, but more well-designed intervention studies are needed to ascertain these effects.

Long-term calcium supplementation may have adverse effects on serum cholesterol and carotid intima-media thickness in postmenopausal women: a double-blind, randomized, placebo-controlled trial

BACKGROUND

Several studies have focused on the effects of calcium intake on serum lipid concentrations in postmenopausal women. However, many premenopausal women are taking calcium supplements in China. To our knowledge, no studies have assessed whether the effects of calcium supplementation on blood lipids are similar between premenopausal and postmenopausal women.

OBJECTIVE

We assessed the effects of calcium supplementation on blood lipid concentrations in premenopausal and postmenopausal women with dyslipidemia.

DESIGN

A total of 190 premenopausal women (30-40 y old) and 182 postmenopausal women (50-60 y old) with dyslipidemia were given 800 mg Ca/d or a placebo for 2 y in a double-blind, randomized, placebo-controlled trial. Blood pressure, fasting glucose and serum lipid concentrations, carotid intima-media thickness (CIMT), dietary nutrient intakes, and physical activity levels were determined at baseline and after 2 y.

RESULTS

There was a significant interaction between calcium supplementation and menopausal status on serum cholesterol concentrations (P < 0.001) and CIMT (P = 0.017). Serum cholesterol concentrations and CIMT were significantly increased in postmenopausal women (P < 0.01) after 2 y. Serum triglyceride, low-density lipoprotein-cholesterol, and high-density lipoprotein-cholesterol concentrations were not affected after 2 y.

CONCLUSIONS

Calcium supplementation in postmenopausal women with dyslipidemia increases serum total cholesterol concentrations and CIMT. In postmenopausal women with dyslipidemia, calcium supplements should be prescribed with caution. This trial was registered at http://www.chictr.org/cn/ as ChiCTR-TRC-12002806.

Effects of high and low fat dairy food on cardio-metabolic risk factors: a meta-analysis of randomized studies

IMPORTANCE

Clear guidelines on the health effects of dairy food are important given the high prevalence of obesity, cardiovascular disease and diabetes, and increasing global consumption of dairy food.

OBJECTIVE

To evaluate the effects of increased dairy food on cardio metabolic risk factors.

DATA SOURCES

Searches were performed until April 2013 using MEDLINE, Science Direct, Google,Embase, the Cochrane Central Register of Controlled Trials, reference lists of articles, and proceedings of major meetings.

STUDY SELECTION

Randomized controlled studies with healthy adults randomized to increased dairy food for more than one month without additional interventions.

DATA EXTRACTION AND SYNTHESIS

A standard list was used to extract descriptive, methodological and key variables from all eligible studies. If data was not included in the published report corresponding authors were contacted.

RESULTS

20 studies with 1677 participants with a median duration of dietary change of 26 (IQR 10-39) weeks and mean increase in dairy food intake of 3.6 (SD 0.92) serves/day were included. Increased dairy food intake was associated with a modest weight gain (+0.59, 95% confidence interval 0.34 to 0.84kg, p<0.0001) but no significant change in waist circumference (0.35 , -0.75 to 1.45 cm); insulin resistance (HOMA –IR -0.94 , -1.93 to 0.05 units); fasting glucose (0.87, -0.27 to 2.01 mg/dl); LDL-cholesterol (1.36 ,-2.38 to 5.09 mg/dl); HDL-cholesterol (0.45, -2.13 to 3.04 mg/dl); systolic (-0.13, -1.73 to 1.98 mmHg) and diastolic blood pressure (0.13, -1.73 to 1.98 mmHg) or C-reactive protein (-0.08, -0.63 to 0.48 mg/L). Results were similar for studies with low-fat and whole-fat dairy interventions.

LIMITATIONS

Most clinical trials were small and of modest quality. .

CONCLUSION

Increasing whole fat and low fat dairy food consumption increases weight but has minor effects on other cardio-metabolic risk factors.

TRIAL REGISTRATION ACTRN

Australian New Zealand Clinical Trials Registry ACTRN12613000401752, http://www.anzctr.org.au.

ETHICS APPROVAL NUMBER

NTX/10/11/115.

Consumption of low-fat dairy foods for 6 months improves insulin resistance without adversely affecting lipids or bodyweight in healthy adults: a randomized free-living cross-over study

Background

Given the highly debated role of dairy food consumption in modulating biomarkers of metabolic syndrome, this study was conducted to examine the influence of long-term (6 month) dairy consumption on metabolic parameters in healthy volunteers under free-living conditions without energy restriction.

Methods

Twenty-three healthy subjects completed a randomized, crossover trial of 12 months. Participants consumed their habitual diets and were randomly assigned to one of two treatment groups: a high dairy supplemented group instructed to consume 4 servings of dairy per day (HD); or a low dairy supplemented group limited to no more than 2 servings of dairy per day (LD). Baseline, midpoint, and endpoint metabolic responses were examined.

Results

Endpoint measurements of body weight and composition, energy expenditure, blood pressure, blood glucose, and blood lipid and lipoprotein responses did not differ (p > 0.05) between the LD and HD groups. HD consumption improved (p < 0.05) plasma insulin (-9%) and insulin resistance (-11%, p = 0.03) as estimated by HOMA-IR compared with the LD group.

Conclusions

Study results suggest that high dairy consumption (4 servings/d) may improve insulin resistance without negatively impacting bodyweight or lipid status under free-living conditions.

Trial registration

Trial registration: NCT01761955

Dietary calcium intake is associated with adiposity, metabolic profile, inflammatory state and blood pressure, but not with erythrocyte intracellular calcium and endothelial function in healthy pre-menopausal women

Recent studies have suggested that dietary Ca may have beneficial effects on adiposity, insulin resistance, dyslipidaemia and blood pressure (BP). One potential mechanism underlying these benefits involves modifications in intracellular Ca concentration ([Ca2+]i). The present study aimed to evaluate the associations of dietary Ca with adiposity, erythrocyte [Ca2+]i, metabolic profile, BP, inflammatory state and endothelial function in healthy pre-menopausal women. In the present cross-sectional study, seventy-six women aged 18–50 years were submitted to the evaluation of dietary intake, anthropometric parameters, body composition, erythrocyte [Ca2+]i, biochemical variables, endothelial function and BP. A FFQ was used to assess usual dietary intake. Endothelial function was evaluated by serum concentrations of adhesion molecules and by the peripheral arterial tonometry (PAT) method, using Endo-PAT 2000®. Participants were allocated into two groups according to Ca intake: low-Ca group (LCG; n 32; < 600 mg/d) and high-Ca group (HCG; n 44; ≥ 600 mg/d). Women in the LCG compared with those in the HCG exhibited, after adjustments for potential confounders, higher values of BMI, waist circumference, waist:height ratio, percentage of body fat, insulin, homeostasis model assessment of insulin resistance, leptin, diastolic and mean BP; and lower levels of HDL-cholesterol, adiponectin and vascular cell adhesion molecule 1. Endothelial function assessed by PAT and [Ca2+]i was similar in both groups. Subjects in the HCG had lower OR for prevalent overweight, obesity, abdominal obesity, insulin resistance, HDL-cholesterol < 600 mg/l and systolic BP >120 mmHg. The findings of the present study suggest that high Ca intake is inversely associated with some cardiovascular risk factors.

Meeting and exceeding dairy recommendations: effects of dairy consumption on nutrient intakes and risk of chronic disease

The 2010 Dietary Guidelines for Americans indicate the US population is experiencing an epidemic of overweight and obesity while maintaining a nutrient-poor, energy-dense diet associated with an increased risk of osteoarthritis, cardiovascular disease, and type 2 diabetes. To build upon the review of published research in the Report of the Dietary Guidelines Advisory Committee on the Dietary Guidelines for Americans, 2010, this article aims to review the scientific literature pertaining to the consumption of dairy foods and the effects of dairy consumption on nutrient intakes and chronic disease risk published between June 2010, when the report was released, and September 2011. PubMed was searched for articles using the following key words: dairy, milk, nutrient intake, bone health, body composition, cardiovascular disease, type 2 diabetes, and blood pressure. Evidence indicates that increasing dairy consumption to the recommended amount, i.e., three servings daily for individuals ≥9 years of age, helps close gaps between current nutrient intakes and recommendations. Consuming more than three servings of dairy per day leads to better nutrient status and improved bone health and is associated with lower blood pressure and reduced risk of cardiovascular disease and type 2 diabetes.

Calcium plus vitamin D3 supplementation facilitated fat loss in overweight and obese college students with very-low calcium consumption: a randomized controlled trial

BACKGROUND

Recent evidence suggests that higher calcium and/or vitamin D intake may be associated with lower body weight and better metabolic health. Due to contradictory findings from intervention trials, we investigated the effect of calcium plus vitamin D3 (calcium+D) supplementation on anthropometric and metabolic profiles during energy restriction in healthy, overweight and obese adults with very-low calcium consumption.

METHODS

Fifty-three subjects were randomly assigned in an open-label, randomized controlled trial to receive either an energy-restricted diet (-500 kcal/d) supplemented with 600 mg elemental calcium and 125 IU vitamin D3 or energy restriction alone for 12 weeks. Repeated measurements of variance were performed to evaluate the differences between groups for changes in body weight, BMI, body composition, waist circumference, and blood pressures, as well as in plasma TG, TC, HDL, LDL, glucose and insulin concentrations.

RESULTS

Eighty-one percent of participants completed the trial (85% from the calcium + D group; 78% from the control group). A significantly greater decrease in fat mass loss was observed in the calcium + D group (-2.8±1.3 vs.-1.8±1.3 kg; P=0.02) than in the control group, although there was no significant difference in body weight change (P>0.05) between groups. The calcium + D group also exhibited greater decrease in visceral fat mass and visceral fat area (P<0.05 for both). No significant difference was detected for changes in metabolic variables (P>0.05).

CONCLUSION

Calcium plus vitamin D3 supplementation for 12 weeks augmented body fat and visceral fat loss in very-low calcium consumers during energy restriction.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT01447433, http://clinicaltrials.gov/).

Association between low bone mass and calcium and caffeine intake among perimenopausal women in Southern Brazil: cross-sectional study

CONTEXT AND OBJECTIVE

Osteoporosis is a skeletal abnormality characterized by reduction and alteration of bone microarchitecture that results in increased fragility and greater predisposition to fractures. Age and low bone mass are the main non-modifiable risk factors for osteoporotic fractures. The modifiable factors include sedentary lifestyle, inadequate calcium intake, excessive alcohol and/or caffeine consumption, smoking and low body weight. The aim here was to evaluate the association between low bone mass and calcium and caffeine intake among perimenopausal women in Southern Brazil.

DESIGN AND SETTING

Cross-sectional study conducted in Porto Alegre and Canoas, Rio Grande do Sul, Brazil.

METHODS

Women (n = 155) of mean age 53.6 ± 9.5 years were evaluated through a cross-sectional study in Southern Brazil. Food frequency questionnaires, bone mass evaluation using calcaneal ultrasound and anthropometric assessment were used.

RESULTS

The prevalence of overweight was 67.7%. In the bone mass screening, 30.3% had low bone mass and 4.5% had osteoporosis. The median calcium intake was 574.94 mg/day and the caffeine intake was 108.11 mg/day. No association was found between bone mass and anthropometric parameters, calcium intake or caffeine intake. It was found that 38.4% of the women had low bone mass.

CONCLUSIONS

No association was found between calcium and caffeine intake and bone mass. High prevalence of low bone mass was observed.

Effects of dairy intake on body weight and fat: a meta-analysis of randomized controlled trials

BACKGROUND

Some intervention studies have suggested that dairy products may influence body weight, but the results remain controversial.

OBJECTIVE

We identified and quantified the effects of dairy consumption on body weight and fat mass from randomized controlled trials (RCTs).

DESIGN

We conducted a comprehensive search of PubMed and EMBASE databases (to April 2012) of English reports of RCTs regarding dairy consumption on body weight, body fat, or body weight and body fat in adults. The results across studies were pooled by using a random-effects meta-analysis.

RESULTS

Twenty-nine RCTs were included with a total of 2101 participants. Overall, consumption of dairy products did not result in a significant reduction in weight (-0.14 kg; 95% CI: -0.66, 0.38 kg; I² = 86.3%). In subgroup analysis, consumption of dairy products reduced body weight in the context of energy restriction or short-term intervention (<1 y) trials but had the opposite effect in ad libitum dietary interventions or long-term trials (≥1 y). Twenty-two RCTs that reported results on body fat showed a modest reduction in the dairy group (-0.45 kg; 95% CI: -0.79, -0.11 kg; I² = 70.9%), and further stratified analysis indicated significant beneficial effects of dairy intervention on body fat in energy-restricted or short-term trials but not in long-term or ad libitum studies.

CONCLUSIONS

This meta-analysis does not support the beneficial effect of increasing dairy consumption on body weight and fat loss in long-term studies or studies without energy restriction. However, dairy products may have modest benefits in facilitating weight loss in short-term or energy-restricted RCTs.

Reproducibility and validity of a food frequency questionnaire to estimate calcium intake in Puerto Ricans

The objective of the study was to assess the reproducibility and validity of a short semiquantitative calcium specific FFQ in a convenience Puerto Rican sample.Reproducibility was tested by the difference between calcium intakes from the FFQ completed twice, with a one month difference; validity was assessed against 6-day diet records (DR) in a sample of students, employees and faculty of the Medical Sciences Campus of the University of Puerto Rico. The statistical analyses performed were Pearson correlations, paired t-test, Bland-Altman plots, cross-classification analysis, Willett's surrogate categories, specificity, sensitivity and predictive value. A total of 93 subjects were included in the study (mean age 28.8 +/- 10.1 years, BMI 25.7 +/- 6.1 kg/m2). Mean estimated calcium intakes were 846.4 +/- 356.9 mg/day for the first FFQ, 801.1 +/- 423.7 mg/day for the repeated FFQ and 845.4 +/- 377.5 mg/day for 6-day DR. No statistical difference was observed between the means by paired t-test (p > 0.05), with significant correlations between means (p < 0.05). The FFQ was found to have a specificity of 65.2%, a sensitivity of 73.5%, a positive predictive value of 86.2% and a negative predictive value of 45.5%. In conclusion, the short FFQ is a valid tool that could be used in the future to assess calcium intake in epidemiological surveys in this group.

Does calcium intake affect cardiovascular risk factors and/or events?

Dietary intervention is an important approach in the prevention of cardiovascular disease. Over the last decade, some studies have suggested that a calcium-rich diet could help to control body weight, with anti-obesity effects. The potential mechanism underlying the impact of calcium on body fat has been investigated, but it is not fully understood. Recent evidence has also suggested that a calcium-rich diet could have beneficial effects on other cardiovascular risk factors, such as insulin resistance, dyslipidemia, hypertension and inflammatory states. In a series of studies, it was observed that a high intake of milk and/or dairy products (the main sources of dietary calcium) is associated with a reduction in the relative risk of cardiovascular disease. However, a few studies suggest that supplemental calcium (mainly calcium carbonate or citrate) may be associated with an increased risk of cardiovascular events. This review will discuss the available evidence regarding the relationship between calcium intake (dietary and supplemental) and different cardiovascular risk factors and/or events.

Intake of dairy calcium and tooth loss among adult Danish men and women

OBJECTIVE

To investigate whether gender differences in tooth loss are influenced by caries risk and sources of dietary calcium intake.

METHODS

This was a cohort study that included 432 Danish adults (30-60 y old) with information on dietary calcium intake in 1982 and 1983 and tooth loss from 1987 and 1988 through 1993 and 1994. Total calcium intake, estimated by a 7-d food record or a a diet history interview, was divided into dairy and non-dairy forms of calcium.

RESULTS

In men, a 10-fold increase in dairy calcium intake was significantly associated with a decreased risk of tooth loss (incidence-rate ratio 0.32, 95% confidence interval 0.15-0.68) even after an adjustment for tooth count in 1987 and 1988, age, education, and civil status (model 1), smoking, alcohol consumption, sucrose intake, and use of vitamin and/or mineral supplements (model 2), time since last dental visit and the presence of oral dryness (model 3), and a high Lactobacillus count (model 4). In women, dairy calcium was not statistically associated with tooth loss in the crude and adjusted models (models 1 to 3). However, the association became highly significant once the Lactobacillus count was included in model 4 (incidence-rate ratio 0.25, 95% confidence interval 0.09-0.73). Non-dairy calcium was not associated with tooth loss in men and women in the fully adjusted models.

CONCLUSION

Dietary calcium intake, particularly calcium from dairy products, seems to protect against loss of teeth in adult men and women. The previous gender differences found in the relation between calcium intake and tooth loss may be the result of differences in the caries risk between genders.

Association between dietary patterns and body composition in a group or Puerto Rican obese adults: a pilot study

OBJECTIVE

Obesity is a public health problem in Puerto Rico. Dietary patterns that include high intakes of energy and sweetened drinks and low consumption of fruits, vegetables and fiber are associated with obesity. The aim of this study is to relate dietary patterns with body composition in obese subjects.

METHODS

Dietary patterns were evaluated using 3-day food records. Body composition was assessed by body weight, hip and waist circumferences and % body fat, and then used to classify subjects by obesity stages using BMI and by low or high risk using WHR or % body fat. The resulting comparison groups were associated with energy, macronutrients, fruits, vegetables, fiber, and sweetened drinks intake and with meal energy density and meal frequency intake. Kruskal Wallis and Mann Whitney tests were used to compare groups and Spearman correlations were used for continuous variables.

RESULTS

Thirty subjects completed the study. By BMI, 30% were obese type I, 33% type II and 37% type III; by WHR, 43% were low risk and 57% high risk; by % body fat, all were high risk. Dietary patterns were similar between groups. WHR was positively correlated with fiber consumption (r = 0.42; p < 0.05) and CHO intake (r = 0.35; p = 0.057).

CONCLUSION

In this pilot study, dietary patterns appeared similar between groups and sound with nutritional recommendations; however, we observed a poor quality of the diet due to very low intakes of fruits, vegetables and fiber and high intakes of sweetened drinks.