Dairy calcium supplementation in overweight or obese persons: its effect on markers of fat metabolism

Dietary patterns are associated with likelihood of hepatic steatosis among US adults

BACKGROUND AND AIM

Non-alcoholic fatty liver disease is a rapidly growing public health problem. In this study, we explored the association between dietary patterns (DPs) and fatty liver and liver function tests.

METHODS

This was a cross-sectional study using data from the US community-based National Health and Nutrition Examination Survey. Participants with data on dietary intake, blood pressure, and status for diabetes mellitus were analyzed. DPs were determined by principal components analysis. Analysis of covariance and logistic regression models accounted for the survey design and sample weights.

RESULTS

Of the 20 643 eligible participants, 45.7% had prevalent fatty liver. Three DPs collectively explained 50.8% of variance in dietary nutrients consumption. The first DP was representative of a diet containing high levels of saturated and mono-unsaturated fatty acids, total fat and carbohydrate; the second DP comprised vitamins, minerals and dietary fibre; and the third DP was mainly representative of polyunsaturated fatty acids. In adjusted multivariable regression models, participants in the top quarter of the second DP had 34% lower odds of prevalent fatty liver (odds ratio 0.66 [95% confidence interval [CI]: 0.43-0.71]), while those in the top quarter of the first DP had 86% higher odds (1.86 [95% CI: 1.42-2.95]) of prevalent fatty liver, relative to participants in the bottom quarter of each of the DPs.

CONCLUSION

Our findings suggest that a diet with high load of vitamins, minerals, and fiber content is associated with a lower prevalence of non-alcoholic fatty liver disease.

A critical review of the role of milk and other dairy products in the development of obesity in children and adolescents

Existing reviews suggest that milk and other dairy products do not play a role in the development of obesity in childhood, but they do make an important contribution to children's nutrient intake. It is thus curious that public health advice on the consumption of dairy products for children is often perceived as unclear. The present review aimed to provide an overview of the totality of the evidence on the association between milk and other dairy products, and obesity and indicators of adiposity, in children. Our search identified forty-three cross-sectional studies, thirty-one longitudinal cohort studies and twenty randomised controlled trials. We found that milk and other dairy products are consistently found to be not associated, or inversely associated, with obesity and indicators of adiposity in children. Adjustment for energy intake tended to change inverse associations to neutral. Also, we found little evidence to suggest that the relationship varied by type of milk or dairy product, or age of the children, although there was a dearth of evidence for young children. Only nine of the ninety-four studies found a positive association between milk and other dairy products and body fatness. There may be some plausible mechanisms underlying the effect of milk and other dairy products on adiposity that influence energy and fat balance, possibly through fat absorption, appetite or metabolic activity of gut microbiota. In conclusion, there is little evidence to support a concern to limit the consumption of milk and other dairy products for children on the grounds that they may promote obesity.

High intake of dairy during energy restriction does not affect energy balance or the intestinal microflora compared with low dairy intake in overweight individuals in a randomized controlled trial

During weight loss, dairy calcium is proposed to accelerate weight and fat-mass loss through increased fecal fat excretion. The primary objective was to investigate if a high-dairy energy-restricted diet is superior to low dairy in terms of changes in body weight, body composition, and fecal fat excretion over 24 weeks. Secondary objectives included fecal energy and calcium excretion, resting energy expenditure, blood pressure, lipid metabolism, and gut microbiota. In a randomized, parallel-arm intervention study, 11 men and 69 women (body mass index, 30.6 ± 0.3 kg/m2; age, 44 ± 1 years) were allocated to a 500-kcal (2100 kJ) –deficit diet that was either high (HD: 1500 mg calcium/day) or low (LD: 600 mg calcium/day) in dairy products for 24 weeks. Habitual calcium intake was ∼1000 mg/day. Body weight loss (HD: –6.6 ± 1.3 kg, LD: –7.9 ± 1.5 kg, P = 0.73), fat-mass loss (HD: –7.8% ± 1.3%, LD: –8.5% ± 1.1%, P = 0.76), changes in fecal fat excretion (HD: –0.57 ± 0.76 g, LD: 0.46 ± 0.70 g, P = 0.12), and microbiota composition were similar for the groups over 24 weeks. However, total fat-mass loss was positively associated with relative abundance of Papillibacter (P = 0.017) independent of diet group. Consumption of a high-dairy diet did not increase fecal fat or accelerate weight and fat-mass loss beyond energy restriction over 24 weeks in overweight and obese adults with a habitual calcium intake of ∼1000 mg/day. However, this study indicates that Papillibacter is involved in body compositional changes.

Relationship between dietary calcium intake and adiposity in female adolescents

BACKGROUND AND OBJECTIVE

The prevalence and magnitude of obesity in children and adolescents increase rapidly. Besides genetic and environmental factors, calcium intake has recently been identified as a dietary factor that is inversely related with body mass index and development of overweight and obesity. The purpose of this study was to assess the correlation between dietary calcium intake and body mass index and fat distribution in female adolescents.

MATERIALS AND METHODS

This was a cross-sectional study where anthropometric variables (weight, height, body mass index, waist and hip circumference) were collected in 244 female adolescents to establish total body adiposity and fat distribution. A 24-hour recall and a food frequency questionnaire were used to assess total calorie, calcium, and dairy products intake.

RESULTS

Calcium intake was inversely related to body mass index (P<.05), waist circumference(P<.05), hip circumference (P>.05), and waist to hip ratio (P<.05).Overweight (8.3%) and obese (0.7%) adolescents had a lower mean calcium intake than adolescents of normal weight (P=.06).

CONCLUSIONS

Dietary calcium intake and, to a lesser extent, consumption of dairy products are inversely related to total and abdominal adiposity, and also to the prevalence of overweight in this group of adolescents.

Intakes of dairy products and calcium and obesity in Korean adults: Korean National Health and Nutrition Examination Surveys (KNHANES) 2007-2009

Background

The possible effects of dairy product intake against obesity have been suggested in animal studies; however, the association is still not well established in epidemiological studies. Few studies in Asian countries with relatively low intake of dairy products exist.

Objective

We investigated the association between dairy products and calcium intake and obesity in Korean population with relatively low intake of dairy products.

Subjects and Methods

Our study population consisted of adults (n = 7173) aged 19–64 among participants of the 2007, 2008 and 2009 Korean National Health and Nutrition Examination Survey who had not made any attempt of intentional weight loss. Dietary intake data from food frequency questionnaire (FFQ) and 24-hour recall were used. Dairy products included milk and yogurt in the FFQ. Obesity was defined as BMI≥25 kg/m².

Results

Higher frequency of dairy product intake was associated with a reduced prevalence of obesity (OR = 0.63; 95% CI = 0.45–0.89 for ≥2 times/day vs. ≤1 time/month; p for trend = 0.003) using the intake data from FFQ. Similarly, high frequency of milk or yogurt intake had an inverse association with obesity. The association between milk and yogurt intake and obesity was similar when the intake from 24-hour recall was examined. Higher calcium intake from dairy products as well as total dietary calcium intake was associated with a decreased prevalence of obesity (OR = 0.83; 95% CI = 0.71–0.98 for highest vs. lowest quintile of dairy calcium intake; p for trend = 0.02, OR = 0.78; 95% CI = 0.64–0.94 for highest vs. lowest quintile of total calcium intake; p for trend = 0.04). The associations appeared to be stronger in women than in men.

Conclusion

These results suggest that high consumption of dairy products is associated with a lower prevalence of obesity and that calcium in dairy products may be one of the components contributing to the association. Further longitudinal studies are warranted to replicate our findings.

Evaluation of calcium supplementation with algae (Lithothamnion muelleri) on metabolic and inflammatory parameters in mice fed a high refined carbohydrate-containing diet

The aim of the present study was to evaluate the potential of calcium supplementation from Lithothamnium muelleri algae on metabolic and inflammatory parameters in mice with increased adiposity. Male mice were fed and divided during 8 weeks in: control (C), a high refined carbohydrate-containing diet (HC), HC diet supplemented with 1% of Lithothamnion muelleri algae (HC + A) and HC diet supplemented with 0.9% calcium carbonate (HC + C). Animals fed HC diet had increased body weight gain and adiposity, serum glucose and cholesterol, glucose intolerance and decreased insulin sensitivity, compared to control diet. However, the HC + A and HC + C groups did not prevent these aspects and were not able to change the CD14 + cells population in adipose tissue of animals fed HC diet. Calcium supplementation with Lithothamnium muelleri algae and calcium carbonate had no protective effect against the development of adiposity, metabolic and inflammatory alterations induced by HC diet.

Dietary patterns in Brazilian patients with nonalcoholic fatty liver disease: a cross-sectional study

OBJECTIVE

Recent evidence suggests that non-alcoholic fatty liver disease is associated with diet. Our aim was to investigate the dietary patterns of a Brazilian population with this condition and compare them with the recommended diet.

METHODS

A cross-sectional study was conducted on 96 non-alcoholic fatty liver disease patients before any dietetic counseling. All patients underwent abdominal ultrasound, biochemical tests, dietary evaluations, and anthropometric evaluations. Their food intake was assessed by a semi-quantitative food-frequency questionnaire and 24-hour food recall.

RESULTS

The median patient age was 53 years, and 77% of the individuals were women. Most (67.7%) participants were obese, and a large waist circumference was observed in 80.2% subjects. Almost 70% of the participants had metabolic syndrome, and 62.3% presented evidence of either insulin resistance or overt diabetes. Most patients (51.5, 58.5, and 61.7%, respectively) exceeded the recommendations for energy intake, as well as total and saturated fat. All patients consumed less than the amount of recommended monounsaturated fatty acids, and 52.1 and 76.6% of them consumed less polyunsaturated fatty acids and fiber, respectively, than recommended. In most patients, the calcium, sodium, potassium, pyridoxine, and vitamin C intake did not meet the recommendations, and in 10.5-15.5% of individuals, the tolerable upper limit intake for sodium was exceeded. The patients presented a significantly high intake of meats, fats, sugars, legumes (beans), and vegetables and a low consumption of cereals, fruits, and dairy products compared with the recommendations.

CONCLUSIONS

Although patients with non-alcoholic fatty liver disease exhibited high energy and lipid consumption, most of them had inadequate intake of some micronutrients. The possible role of nutrient-deficient intake in the development of non-alcoholic fatty liver disease warrants investigation.

Effect of calcium intake on fat oxidation in adults: a meta-analysis of randomized, controlled trials

Calcium intake is likely to increase body fat loss during energy restriction. Part of this effect may be explained by increased fat oxidation in the presence of a similar energy balance, yet studies have not provided a conclusive answer. Therefore a meta-analysis was performed to determine whether chronic or acute high calcium intake increases fat oxidation. Randomized controlled trials of high calcium intake in human adults where measures of fat oxidation were taken were included. A random-effects meta-analysis was performed on outcomes expressed as standardized mean differences. Chronic high calcium intake increased fat oxidation by a standardized mean difference of 0.42 (95% confidence intervals: 0.14, 0.69; P= 0.003; estimated to correspond to an 11% increase), displaying low heterogeneity (I(2) = 18%), which was more prominent when habitual calcium intake was low (<700 mg d(-1) ). Acute high calcium intake increased fat oxidation by a standardized mean difference of 0.41 (0.04, 0.77; P = 0.03), with low heterogeneity (I(2) = 19%), yet sensitivity analysis revealed that this effect was relatively weak. In conclusion, chronic high calcium intake is likely to increase rates of fat oxidation. The effects of acute high calcium intake appear to point in the same direction, but further work is needed to permit a greater degree of certainty.

Mechanistic roles for calcium and vitamin D in the regulation of body weight

Low intakes of calcium and inadequate vitamin D status often cluster with higher prevalence rates of obesity. Consequently, there has been much interest in the mechanisms by which calcium and vitamin D could regulate body weight and adiposity. This review has focused on randomized controlled trials (RCTs) that have manipulated these nutrients and studied pathways of energy balance. Overall, there is consistent evidence that calcium and vitamin D increase whole body fat oxidation after single and multiple meals, and that calcium promotes a modest energy loss through increased faecal fat excretion. The evidence is equivocal for a greater diet-induced thermogenesis, increased lipolysis, suppression of key lipogenic enzymes, decreased hunger ratings or reduced energy/macronutrient intake. Emerging evidence suggests a potential improvement in insulin sensitivity following vitamin D that would impinge on food intake and substrate oxidation. However, the very few RCTs on supplemental vitamin D and energy balance have not explored postprandial avenues of the hormone's actions. Future efforts in this area need to define the threshold intake of these nutrients that would maximize metabolic and gastrointestinal outcomes. Such studies would provide a platform for endorsing the non-skeletal role of calcium and vitamin D in human pathophysiology.

Calcium and vitamin D in obesity

New and more effective nutritional measures are urgently needed for the prevention of obesity. The role of Ca and vitamin D in obesity has been recently implicated. Low Ca intake and low vitamin D status have been linked with an increased risk of obesity in epidemiological studies; however, clinical intervention trials designed to test this association have produced controversial results. The suggested anti-obesity mechanisms of Ca and vitamin D include the regulation of adipocyte death (apoptosis), adipogenesis and lipid metabolism. Dietary Ca has been also shown to increase faecal fat excretion. The potential role of Ca and vitamin D in shifting energy balance towards a more negative state is an area of considerable interest. Ultimately, a review of recent research findings does not allow the reaching of a definitive conclusion that increasing Ca intake and rising vitamin D status will influence fat mass and body weight or decrease the risk of obesity and overweight.

Calcium, dairy products, and energy balance in overweight adolescents: a controlled trial

BACKGROUND

Dairy product and calcium consumption have been associated with modifying body fat and body weight in children and adults.

OBJECTIVE

In overweight adolescent boys and girls, we aimed to determine the effect of the doubling of habitual calcium intake to the recommended intake from dairy or calcium carbonate on energy balance and purported mechanisms including fecal fat excretion, macronutrient use, and parathyroid hormone suppression.

DESIGN

Twenty-five girls with a mean (±SD) BMI (in kg/m(2)) of 33 ± 5 and 17 boys with a BMI of 28 ± 5, aged 12-15 y, participated in two 3-wk controlled feeding sessions that used a crossover design in random order as a summer research camp. In one session, 756 mg Ca/d was consumed; in the other session, an additional 650 mg Ca/d was provided as dairy or calcium carbonate supplements that were matched to the control in macronutrient content. Total energy and macronutrient intakes were controlled and were the same for the 2 sessions for each subject. Primary outcome measures were energy balance, fecal fat excretion, lipid oxidation, and postprandial energy expenditure.

RESULTS

There were no effects of quantity or source of calcium on energy or fat balance, despite calcium-induced increases (P <0.01) in postprandial serum parathyroid hormone suppression.

CONCLUSION

These data lend little evidence to support the proposed mechanisms for the relation between an increase in calcium intake from calcium carbonate or dairy and weight loss or weight maintenance in children. This trial was registered at clinicaltrials.gov as NCT00592137.

The search for compounds that stimulate thermogenesis in obesity management: from pharmaceuticals to functional food ingredients

The concept of managing obesity through the stimulation of thermogenesis is currently a focus of considerable attention by the pharmaceutical, nutraceutical and functional food industries. This paper first reviews the landmark discoveries that have fuelled the search for thermogenic anti-obesity products that range from single-target drugs to multi-target functional foods. It subsequently analyses the thermogenic and fat-oxidizing potentials of a wide array of bioactive food ingredients which are categorized under methylxanthines, polyphenols, capsaicinoids/capsinoids, minerals, proteins/amino acids, carbohydrates/sugars and fats/fatty acids. The main outcome of this analysis is that the compounds or combination of compounds with thermogenic and fat-oxidizing potentials are those that possess both sympathomimetic stimulatory activity and acetyl-coA carboxylase inhibitory property, and are capable of targeting both skeletal muscle and brown adipose tissue. The thermogenic potentials of products so far tested in humans range from marginal to modest, i.e. 2-5% above daily energy expenditure. With an increasing number of bioactive food ingredients awaiting screening in humans, there is hope that this thermogenic potential could be safely increased to 10-15% above daily energy expenditure - which would have clinically significant impact on weight management, particularly in the prevention of obesity and in improving the long-term prognosis of post-slimming weight maintenance.

Associations between dairy consumption and body weight: a review of the evidence and underlying mechanisms

As the incidence of obesity is reaching 'epidemic' proportions, there is currently widespread interest in the impact of dietary components on body-weight and food intake regulation. The majority of data available from both epidemiological and intervention studies provide evidence of a negative but modest association between milk and dairy product consumption and BMI and other measures of adiposity, with indications that higher intakes result in increased weight loss and lean tissue maintenance during energy restriction. The purported physiological and molecular mechanisms underlying the impact of dairy constituents on adiposity are incompletely understood but may include effects on lipolysis, lipogeneis and fatty acid absorption. Furthermore, accumulating evidence indicates an impact of dairy constituents, in particular whey protein derivatives, on appetite regulation and food intake. The present review summarises available data and provides an insight into the likely contribution of dairy foods to strategies aimed at appetite regulation, weight loss or the prevention of weight gain.

Risk factors for adult overweight and obesity: the importance of looking beyond the 'big two'

OBJECTIVE

To compare two traditional (high dietary lipid intake and non-participation in high-intensity physical exercise, namely the 'Big Two' factors) versus three nontraditional (short sleep duration, high disinhibition eating behavior, and low dietary calcium intake) risk factors as predictors of excess body weight and overweight/obesity development.

METHOD

Adult participants aged 18-64 years of the Quebec Family Study were selected for cross-sectional (n = 537) and longitudinal (n = 283; 6-year follow-up period) analyses. The main outcome measure was overweight/obesity, defined as a BMI ≥ 25 kg/m(2).

RESULTS

We observed that both the prevalence and incidence of overweight/obesity was best predicted by a combination of risk factors. However, short sleep duration, high disinhibition eating behavior and low dietary calcium intake seemed to contribute more to the risk of overweight and obesity than high dietary lipid intake and non-participation in high-intensity physical exercise. Globally, the risk of being overweight or obese was two-fold higher for individuals having the three nontraditional risk factors combined (OR 6.05; 95% CI 4.26-7.88) compared to those reporting a high percentage of lipids in their diet together with no vigorous physical activity in their daily schedule (OR 2.95; 95% CI 2.18-3.73). Furthermore, the risk of overweight/obesity was also higher for the combination of any two of the nontraditional risk factors than for the combination of the 'Big Two' factors.

CONCLUSION

These results are concordant with previous reports showing that obesity is a multifactorial condition, and emphasize the importance of looking beyond reported measures of the 'Big Two' factors.

Dairy food consumption and obesity-related chronic disease

Dairy food comprises a range of different products with varying nutritional components. In the context of a healthy diet, dairy food may provide protection against and amelioration of chronic diseases related to obesity. These include overweight, insulin resistance/metabolic syndrome/type 2 diabetes, hypertension/stroke, and cardiovascular disease. Eliciting how dairy food may have this impact represents a challenge for modern nutritional science and requires an integration of knowledge from observational studies of population dietary patterns and disease prevalence, and experimental studies testing the effect of dairy food consumption. It also benefits from the recent identification of biomarkers of dairy fat intake and from mechanistic studies that support the plausibility of the observed effects. Future research might discriminate between types of dairy foods and focus on the synergy provided by the food matrix, rather than simply the component parts of the food.

Postprandial energy metabolism in the regulation of body weight: is there a mechanistic role for dietary calcium?

There has been much interest in the mechanisms by which calcium may attenuate weight gain or accelerate body fat loss. This review focuses on postprandial energy metabolism and indicates that dietary calcium increases whole body fat oxidation after single and multiple meals. There is, as yet, no conclusive evidence for a greater diet induced thermogenesis, an increased lipolysis or suppression of key lipogenic enzyme systems. There is however convincing evidence that higher calcium intakes promote a modest energy loss through increased fecal fat excretion. Overall, there is a role for dietary calcium in human energy metabolism. Future studies need to define threshold intakes for metabolic and gastrointestinal outcomes.

Investigation of the effect of high dairy diet on body mass index and body fat in overweight and obese children

OBJECTIVE

To investigate whether an increase in dairy food consumption improves the changes in BMI and adiposity in children on an energy restricted diet.

METHODS

Overweight and obese children (n = 120, age: 12-18 y, BMI: 27-40 kg/m2) were randomized to receive a calorie restricted diet providing a 500 kcal/d deficit from total energy expenditure and two (n = 40), three (n = 40) or four (n = 40) servings of dairy products/day. Anthropometric measurements in addition to serum hs-CRP and lipid profile were measured at baseline and after 12 weeks.

RESULTS

Among the 96 children who completed the study, significant reductions in overall BMI, BMI z-score, weight, total body fat percentage and total body fat mass were observed (p < 0.001) but these reductions were not significantly affected by increasing dairy intake (p > 0.05). Overall waist/hip ratio, Serum vitamin D and lipid profile did not change significantly (p > 0.05) apart from a significant increase in HDL-cholesterol (p < 0.001) which was independent of dairy intake (p > 0.05).

CONCLUSION

Increased intake of dairy products does not lead to an augmented change in BMI, weight and body fat in overweight and obese children beyond what is achieved by calorie restriction.

The role of dairy foods and dietary calcium in weight management

Overweight and obesity are the foremost public health problems in the U.S., other industrialized countries, and is rapidly increasing in developing countries. Obesity is a multifaceted disease which requires multiple approaches to successfully combat its increase. Nutritional factors play a key role and include modification of energy balance, intake and expenditure, as well as other factors. Emerging scientific evidence over the past decade suggests that dairy foods may be beneficial when included in a moderate energy restricted diet and possibly for weight maintenance as well. This paper provides a review of some of the scientific evidence that has examined the effect of dairy foods and dietary calcium on weight management. Topic areas presented are observational or retrospective studies with adults as well as children and adolescents; randomized clinical trials on body weight and composition, energy expenditure, substrate oxidation and fecal fat loss; research from animal and in vitro studies provide possible mechanisms of action.

Effect of calcium from dairy and dietary supplements on faecal fat excretion: a meta-analysis of randomized controlled trials

Observational studies have found that dietary calcium intake is inversely related to body weight and body fat mass. One explanatory mechanism is that dietary calcium increases faecal fat excretion. To examine the effect of calcium from dietary supplements or dairy products on quantitative faecal fat excretion, we performed a systematic review with meta-analysis. We included randomized, controlled trials of calcium (supplements or dairy) in healthy subjects, where faecal fat excretion was measured. Meta-analyses used random-effects models with changes in faecal fat excreted expressed as standardized mean differences, as the studies assessed the same outcome but measured in different ways. An increased calcium intake resulted in increased excretion of faecal fat by a standardized mean difference of 0.99 (95% confidence intervals: 0.63-1.34; P < 0.0001; expected to correspond to approximately 2g day(-1)) with moderate heterogeneity (I(2) = 49.5%) indicating some inconsistency in trial outcomes. However, the dairy trials showed homogeneous outcomes (I(2)=0%) indicating consistency among these trials. We estimated that increasing the dairy calcium intake by 1241 mg day(-1) resulted in an increase in faecal fat of 5.2 (1.6-8.8) g day(-1). In conclusion, dietary calcium has the potential to increase faecal fat excretion to an extent that could be relevant for prevention of weight (re-)gain. Long-term studies are required to establish its potential contribution.