Whole-fat or reduced-fat dairy product intake, adiposity, and cardiometabolic health in children: A systematic review

Dietary guidelines commonly recommend that children aged \u3e2 y consume reduced-fat dairy products rather than regular- or whole-fat dairy. In adults, most studies have not found the consumption of whole-fat dairy products to be associated with increased cardiometabolic or adiposity risk. Associations in children could differ due to growth and development. We systematically reviewed the literature in indexed, peer-reviewed journals to summarize pediatric studies (children aged from 2 to 18 y) assessing associations between whole- and reduced-fat dairy intake and measures of adiposity as well as biomarkers of cardiometabolic disease risk, including the serum lipid profile, blood pressure, low-grade chronic inflammation, oxidative stress, and measures of glucose homeostasis. For the purposes of this review, a “whole-fat” dairy product was defined as a product with the natural fat content, whereas a “reduced-fat” dairy product was defined as a product with some or all of the fat removed (including “low-fat” and “skim” versions). A total of 29 journal articles met our criteria for inclusion. The majority were conducted in the United States and were prospective or cross-sectional observational studies, with only 1 randomized controlled trial. Studies were consistent in reporting that whole-fat dairy products were not associated with increased measures of weight gain or adiposity. Most evidence indicated that consumption of whole-fat dairy was not associated with increased cardiometabolic risk, although a change from whole-fat to reduced-fat dairy improved outcomes for some risk factors in 1 study. Taken as a whole, the limited literature in this field is not consistent with dietary guidelines recommending that children consume preferably reduced-fat dairy products. High-quality randomized controlled trials in children that directly compare the effects of whole-fat compared with reduced-fat dairy intake on measures of adiposity or biomarkers of cardiometabolic disease risk are needed to provide better quality evidence in this area

Vitamin D Deficiency in Obese Children and Its Relationship to Insulin Resistance and Adipokines

Low-serum concentrations of 25-hydroxyvitamin D [25(OH)D] are associated with insulin resistance in adults. Less data are available in pediatric populations. Serum 25(OH)D serum concentrations were assessed in 125 obese and 31 nonobese children (age 11.9 ± 2.7 y, range 6–16 y, 49% male) living in Bonn, Germany. The relationship between 25(OH)D, measured by liquid chromatography-tandem mass spectrometry, and measures of insulin sensitivity and adipokines adiponectin and resistin were analyzed. Seventy-six % of subjects were 25(OH)D deficient (<20 ng/mL). Higher insulin, homeostasis model assessment-insulin resistance (HOMA-IR r = −0.269, P = 0.023), and hemoglobin A1c (HbA1c) as well as lower quantitative insulin-sensitivity check index (QUICKI r = 0.264, P = 0.030) values were found in obese children with lower 25(OH)D concentrations even after adjustment for gender, age, and body mass index. Furthermore, 25(OH)D correlated significantly with adiponectin, but not with resistin. Our results suggest that hypovitaminosis D is a risk factor for developing insulin resistance independent of adiposity

Dietary n-3-polyunsaturated fatty acids and energy balance in overweight or moderately obese men and women: a randomized controlled trial

<p>Abstract</p> <p>Background</p> <p>Dietary n-3-polyunsaturated fatty acids (n-3-PUFA) have been shown to reduce body weight and fat mass in rodents as well as in humans in one small short-term study. We conducted this controlled randomized dietary trial to test the hypothesis that n-3-PUFA lower body weight and fat mass by reducing appetite and <it>ad libitum </it>food intake and/or by increasing energy expenditure.</p> <p>Methods</p> <p>Twenty-six overweight or moderately obese (body mass index 28–33 kg/m²) men and women were included, and received either a diet rich in n-3-PUFA from both plant and marine sources or a control diet. Diets were administered in an isocaloric fashion for 2 weeks followed by 12 weeks of <it>ad libitum </it>intake. The n-3-PUFA and control diets were identical in all regards except for the fatty acid composition. All foods were provided to subjects, and leftovers were weighed back to assess actual food intake accurately for each day of the study. This design gave us 80% power to detect a difference in weight change between the n-3-PUFA and control diet groups of 2.25 kg at an α-error level of 5%.</p> <p>Results</p> <p>Both groups lost similar amounts of weight when these diets were consumed <it>ad libitum </it>for 12 weeks [mean (SD): -3.5 (3.7) kg in the control group vs. -2.8 (3.7) kg in the n-3-PUFA group, F_(1,24)= 13.425, p = 0.001 for time effect; F_(1,24)= 0.385, p = 0.541 for time × group interaction]. Consistent with this finding, we also found no differences between the n-3-PUFA and control groups with regard to appetite as measured by visual analogue scale, <it>ad libitum </it>food intake, resting energy expenditure as measured by indirect calorimetry, diurnal plasma leptin concentrations, or fasting ghrelin concentrations.</p> <p>Conclusion</p> <p>Our results suggest that dietary n-3-PUFA do not play an important role in the regulation of food intake, energy expenditure, or body weight in humans.</p

Whole fat dairy products do not adversely affect adiposity or cardiometabolic risk factors inchildren in the Milky Way study: A double blind randomized controlled pilot study

Background Limited evidence supports the common public health guideline that children \u3e 2 y of age should consume dairy with reduced fat content. Objectives We aimed to investigate the effects of whole-fat compared with reduced-fat dairy intake on measures of adiposity and biomarkers of cardiometabolic risk in healthy 4- to 6-y-old children. Methods The Milky Way Study enrolled 49 children (mean ± SD age: 5.2 ± 0.9 y; 47% girls) who were habitual consumers of whole-fat dairy, then randomly assigned them in a double-blind fashion to remain on whole-fat dairy or switch their dairy consumption to reduced-fat products for 3 mo. Primary endpoints included measures of adiposity, body composition, blood pressure, fasting serum lipids, blood glucose, glycated hemoglobin (HbA1c), and C-reactive protein (CRP) and were assessed at baseline and study end. Pre- and postintervention results were compared using linear mixed models, adjusted for growth, age, and sex. Results Dairy fat intake was reduced by an adjusted (mean ± SEM) 12.9 ± 4.1 g/d in the reduced-fat compared with the whole-fat dairy group (95% CI: –21.2, –4.6 g/d; P = 0.003), whereas dietary energy intakes remained similar (P = 0.936). We found no significant differential changes between dairy groups in any measure of adiposity, body composition, blood pressure, or fasting serum lipids, glucose, HbA1c, and CRP. Conclusions Our results suggest that although changing from whole-fat to reduced-fat dairy products does reduce dairy fat intake, it does not result in changes to markers of adiposity or cardiometabolic disease risk in healthy children