National Dairy Council Research Articles

Dietary potassium and sodium impact blood pressure in adolescence

Adolescent blood pressure is a strong predictor of adult BP but the role of dietary sodium and potassium on adolescent BP is unclear. Our goal was to estimate effects of dietary sodium, potassium and the ratio of the two on adolescent BP. Data from 2379 girls, initially ages 9–10, and followed 10 years in the National Growth and Health Study, was used. Mean sodium and potassium intakes were 3.1 and 2.0 g respectively from an average of 6.6 sets of 3‐ day diet records. While sodium and potassium intakes were highly correlated (r=0.59), they had opposite BP effects. ANCOVA & repeated measures mixed models were used to estimate mean BP change over 10 yrs and at 18–20 yrs of age, controlling for height, race, TV/video time, activity, total energy, low‐fat dairy, BMI. Adjusted mean BP levels (mean age=18.3 yrs) declined linearly with increasing tertiles of potassium intake (SBP:109.5, 109.1, 108.4 mmHg; DBP:66.2, 65.2, 64.9 mmHg; p‐trend<0.05 for both). BP also declined with increasing tertiles of K:Na ratio (SBP:109.6, 109.5, 108.0 mmHg; DBP:65.9, 65.6, 64.9 mmHg; ns). In longitudinal models, girls with the highest K:Na ratio (>;0.75) & potassium intakes (>;2275 mg) had statistically significantly lower systolic (but not diastolic) BP levels throughout adolescence. Sodium intake had no effect on adolescent BP. This study suggests that dietary potassium may play a more important role than sodium in determining adolescent BP levels.Grant Funding Source: NIDDK and National Dairy Council

Partial Least Squares Regression Discriminated High and Low Total Weight Loss Groups in Overweight and Obese Adults Consuming an Energy Restricted Diet.

Multivariate analysis can reduce data to lower dimensional graphics that display group clusters not observed with other techniques. We used PCA and PLS to interpret data from a controlled feeding trial with an energy restricted diet in 71 overweight and obese adults. Clinical, endocrine, and inflammatory markers, body composition, and energy intake and energy expenditure measurements were included in the analyses. Analyses were conducted in R (ver 2.11.1). PCA found two clusters of participants by sex when post‐intervention data were plotted on the first two components. Subsequent PLS analysis of the sex adjusted data discriminated participants grouped by high and low weight loss along Latent Variable 1 (LV1) and LV2. Loadings related to low weight loss included total fat mass, blood lipids and sedentary activity. Loadings related to higher weight loss included physical activity. PLS projections indicated that subjects who had greater weight loss engaged in more physical activity. Since subjects maintained normal activities, our results suggest innate person‐to‐person differences in sedentary behavior and physical activity have a large impact on weight loss even with a highly‐controlled weight loss paradigm.Funding: National Dairy Council; USDA, ARS, WHNRC; Dairy Council of California; CTSC, University of California (1M01RR19975–01), National Center for Medical Research (UL1 RR024146)

Only High Vitamin D Intake Cuts Fracture Risk

Only High Vitamin D Intake Cuts Fracture Risk

Effect of dairy foods on cell adhesion molecules (CAMs)

CAMs mediate atherosclerosis and thus are considered biomarkers of endothelial dysfunction. Elevated levels of CAMs predict heart disease risk and research has focused on strategies to lower them. Yet, studies of how diet affects CAMs are lacking. This study examined the effect of dairy foods on CAMs serum levels. Adults with untreated hypertension (n=23) were fed 3 experimental diets (5 wk each) in a randomized crossover study design. Diets included a dairy‐rich, high fruits and vegetables diet (D‐F&V; 30% fat, 7% saturated fat [SFA], 3.4 servings [svg]/d dairy, 9.6 svg/d F&V), a high fruits and vegetables diet (F&V; 30% fat, 7% SFA, 0.4 svg/d dairy, 9.6 svg/d F&V), and an average Western diet (AWD; 36% fat, 15% SFA, 0.4 svg/d dairy, 3.6 svg/d F&V). The D‐F&V diet reduced VCAM‐1 (547 ± 33 ng/mL) by about 16% compared with the F&V diet (649 ± 33 ng/mL, p < 0.05) and the AWD diet (650 ± 34 ng/mL, p < 0.05). Compared with the AWD diet, ICAM‐1 (242 ± 14 ng/mL) was significantly reduced by both the D‐F&V (225 ± 14 ng/mL, p < 0.05) and F&V diets (226 ± 14 ng/mL, p < 0.05). E‐selectin and P‐selectin followed a similar pattern, with the D‐F&V diet eliciting the lowest levels (D‐F&V vs. AWD, p < 0.02; D‐F&V vs. F&V, p < 0.1; F&V vs. AWD, p=ns). Collectively, these results suggest that dairy foods may have beneficial effects on endothelial function in hypertension.Funding: National Dairy Council, GCRC Penn State University NIH M01 RR10732

The Effect of Milk Components on the Immune Response to a Pneumonia Vaccine: A Randomized Placebo‐controlled Clinical Trial

Interventions aimed at improving immune function in the elderly could significantly reduce their risk of infectious disease and resulting mortality. The immune benefits of breast milk consumption in human infants are well established and suggest bovine milk components may also help enhance immune function in older populations. The objectives of this study were to evaluate the effects of a milk‐protein supplement on immune function in people at risk of immune senescence (IS). We enrolled 160 subjects over age 50 who were randomized to consume a milk‐based or control supplement for 8 weeks. Immune function was evaluated by measuring the antibody response to a pneumonia vaccine. IgG antibodies were measured before and after vaccine by multi‐analyte immunodetection system. Seroconversion was defined as a 4‐fold increase in titer. Risk of IS was evaluated by measuring a previously described marker of immune function, indolamine 2,3‐dioxygenase (IDO). IDO activity was defined as the ratio of the serum concentration of enzyme product (kynurenine) to substrate (tryptophan), measured by HPLC. Results from this study show a milk intervention significantly (p<0.05) increased the antibody response to 5 vaccine serotypes and the average seroconversion rate. These results highlight the relevance of diet for improving age‐related immune decline in individuals at risk of immune senescence.Grant Funding Source: Dairy Management, Inc, National Dairy Council, the UC Discovery Grant

A nine month strength training program increases resting metabolic rate

Sixty one healthy adults (18–35 y) completed a supervised resistance training (RT) program (3 d/wk) with protein supplementation for nine months. Subjects were randomly assigned to a whey protein concentrate (WP, n=18), soy protein isolate (SP, n=21) or carbohydrate (CHO, n=22) supplementation group (20 g/d). Participants were advised to follow a diet providing adequate energy and ~1.0 g protein/kg body weight plus supplement. Resting metabolic rate (RMR), total triiodothyronine (TT3) and total thyroxine (TT4) were measured. RMR significantly increased from baseline to the end of the study (p=.002) with the largest increase observed in WP (108±177 kcal/d) followed by SP (72±109 kcal/d), and CHO (44±180 kcal/d). The RMR changes were not significant between groups. Plasma TT3 was different at three months of RT between WP and SP (0.45±0.18 ng/ml, p=.048), no other differences were observed at six or nine months. Plasma TT4 decreased from baseline to three months in CHO (−1.55±0.22 μg/dl, p=.000) and WP (−1.37±0.42 μg/dl, p=.025). TT4 values were back to baseline at six months in WP and at nine months in CHO. There were no associations between the changes in RMR and TT3 or TT4 in any group. These results suggest that a nine month progressive RT program significantly increases resting RMR. [Supported by National Dairy Council, USA].

Association between Vitamin D Metabolites in Fat Tissue and Serum 25‐hydroxyvitamin D in Overweight and Obese Adults

Cholecalciferol has been measured in human white adipose tissue (WAT), but little is known about the relationship between the other circulating vitamin D metabolites and WAT. We measured concentrations of 25(OH)D and 1,25(OH)2D in subcutaneous fat tissue from 20 overweight and obese subjects participating in a weight loss intervention (Van Loan, 2011). WAT biopsies were obtained pre‐ and post‐intervention from the gluteal region and were analyzed for 25(OH)D and 1,25(OH)2D by LC/MS/MS (Blum, 2008). Serum 25(OH)D and 1,25(OH)2D were measured by RIA. Mean adipose 25(OH)D concentrations were 2.24 ± 1.0 ng/g pre‐ and 2.39 ± 1.1 ng/g post‐intervention, but 1,25(OH)2D concentrations were undetectable. Pre‐ and post‐intervention WAT 25(OH)D concentrations were correlated (r = 0.5482, P = 0.0185) and there was a significant positive association between subcutaneous fat 25(OH)D concentrations and serum 25(OH)D concentrations (r = 0.5140, P = 0.0011) across a range of body weight and adiposity. This suggests that similar to the parent compound, 25(OH)D deposition in human WAT is directly dependent on circulating 25(OH)D. The active compound, 1,25(OH)2D, may not be stored in appreciable amounts. Funding: National Dairy Council; USDA, ARS, WHNRC; Dairy Council of California; CTSC, University of California (1M01RR19975‐01), National Center for Medical Research (UL1 RR024146)Grant Funding Source : Dairy Research Institute

Effects of fruits and vegetables and dairy foods on platelet activity

Our past research has shown that a dairy‐rich diet produces an ideal intracellular environment (significantly lower intracellular calcium (Ca)i to magnesium ratio) compared with two low dairy/calcium diets. This study examined the effect of dairy foods on platelet activity, which is regulated by (Ca)i. Adults with untreated hypertension (n=16) were fed 3 experimental diets (5 wk each) in a randomized crossover study design. Diets included a dairy rich, high fruits and vegetables diet (D‐F&V; 30% fat, 7% saturated fat [SFA], 3.4 servings [svg]/d dairy, 9.6 svg/d F&V), a high fruits and vegetables diet (F&V; 30% fat, 7% SFA, 0.4 svg/d dairy, 9.6 svg/d F&V), and an average Western diet (AWD; 36% fat, 15% SFA, 0.4 svg/d dairy, 3.6 svg/d F&V). (Ca)i mobilization in platelets was measured after treatment with vasopression (VP) by flow cytometry. As expected, VP induced a rapid elevation in (Ca)i from baseline on all diets (p's < 0.01). Peak change in (Ca)i was 130% higher on AWD vs D‐F&V and F&V diets (p's < 0.05). Serum P‐selectin, a marker of platelet activation, was higher on AWD vs. D‐F&V diet (p < 0.02), while the F&V diet was not different from either. Taken together, the AWD appears to detrimentally affect platelet properties in hypertensive subjects compared with diets high in fruits and vegetables; and dairy foods may offer additional benefits.Funding: National Dairy Council, GCRC of Penn State University NIH M01 RR10732

Effects of dairy foods in a moderate energy restricted diet on inflammatory markers and plasma zinc in overweight and obese adults

Pro-inflammatory cytokines and acute phase proteins are often elevated in obesity, while plasma Zn is often lower. Healthy overweight and obese (BMI = 28–37) men (n=18) and women (n=53) were randomly assigned to an adequate dairy (AD: 3–4 servings/d) or low dairy (LD: ≤ 1 serving/d) 12 wk controlled diet of 500 kcal/d reduction from baseline energy needs. Body fat (BF), lean body mass (LBM), and fasting levels of circulating insulin, leptin, adiponectin, IL1-β, IL-6, IL-8, TNF-α, PAI-1, hsCRP and Zn were measured. Mean weight loss was 6.1 kg. Significant decreases (p<0.05) from baseline to 12 wk included body weight (6.8%), BF (14.2%), LBM (1.6%), insulin (12.2%), leptin (24.9%), PAI-1 (12.7%) & hsCRP (22.8%). All decreases correlated with BF loss, but no differences were observed between AD & LD. Plasma Zn increased (p<0.05) in the AD group (9.5%), which was not explained by dietary Zn intake. IL1- β and IL-6 changes were correlated with the change in LBM; if LBM was conserved IL1- β and IL-6 levels decreased (p<0.05). In summary, a modest weight loss of 6 kg over 12 wks improved markers of inflammation, and adding dairy foods to the weight loss diet increased plasma Zn. Funding: National Dairy Council; USDA, ARS, WHNRC; Dairy Council of CA; CTSC, Clinical Research Center at the University of CA (1M01RR19975-01), and National Center for Medical Research (UL1 RR024146)

The synergistic effect of calcium (Ca), alpha‐linolenic acid (ALA) and conjugated‐linoleic acid (CLA) on osteoblastogenesis and adipogenesis

Recent research points into connections between bone and adipose tissue with major players being Ca, ALA and CLA. The aim of this study was to investigate possible synergistic effects among ALA, CLA and Ca on preosteoblastic MC3T3‐E1, preadipocytic MC3T3‐L1 and stromal ST2 cell proliferation. Low or high (0.5 or 2 mM) Ca in media containing individual or mixture of ALA (8.75–50 μM; n‐6/n‐3=4/1) and CLA isomers (20 μM of c9, t11/t10, c12‐CLAs; 80/10, 90/10, 90/5% respectively) were treated for 6 days (triplicate). Cell proliferation was determined by resazurin salt solution, and florescence was measured at 590 nm. ST2 and 3T3‐E1 cell proliferation was higher at 0.5 mM and lower at 2 mM Ca; Reversed was true for 3T3‐L1 cells (p&lt;0.05). At both Ca levels, individual or mixture of ALA and CLA did not affect 3T3‐L1 cells. In ST2 cells, the effect of ALA was lowered by adding CLA (80/10; 90/10) at 0.5 mM Ca, whereas at 2 mM Ca, ALA+CLA (80/10) further enhanced proliferation. In 3T3‐E1 cells, even though ALA significantly increased proliferation at 0.5mM Ca, its effect was markedly lowered by addition of CLA at all combinations/both Ca levels. Overall, providing high Ca may reduce adipogenesis, but enhance osteoblastogenesis. In a proliferative stage, a synergistic effect among Ca, ALA and CLA on bone/fat cell may not be substantial, but is significant in increasing progenitor stromal cell formation. DMI#1673 and FSU‐CRC#119532Grant Funding Source: National Dairy Council

Proportion of the U.S. Population Consuming a “Low Carbon” Diet

Results of studies on the environmental impacts of food production and transport have suggested that individuals can lower their “carbon footprints” by reducing consumption of animal‐based foods and increasing consumption of plant‐based foods. Specific recommendations for dietary changes to lower environmental impacts have included reduced use of beef, cheese, air‐freighted fish, tropical fruits, and highly processed sweets, snacks and chocolate. These recommendations provide a framework on which to evaluate the impact of adopting a “low carbon diet” on nutrient intakes and measures of diet quality. Using food consumption data reported in NHANES 2003–2006, 2‐day average mean intakes of beef, cheese, tropical fruits (mangos, papayas, bananas, pineapple and starfruit), and the highly processed foods were estimated for 6 age/sex subpopulations of the U.S. population age 9 y and older. Individuals consuming &lt; 75% of the subpopulation mean intakes of beef, &lt; 90% of the mean intakes of cheese and highly processed foods, and &lt; 50% of the mean intakes of tropical fruits were categorized as consuming a diet consistent with “low carbon” goals. Overall, the diets of approximately 11–15% of individuals 9 y and older met the “low carbon” criteria. It will be important to determine the impact of this dietary pattern on nutrient adequacy and overall diet quality. Supported by the National Dairy Council.

Protein supplementation during 6 mo weight loss enhances body composition changes in older women

Adverse increases in adiposity and reductions in fat free mass (FFM) are age related changes in body composition and are linked to declines in physical function in older women. Higher protein intake in weight loss may augment fat mass (FM) loss and attenuate FFM loss, which may benefit function. This study assessed effects of 6 mo weight loss supplemented with powdered protein or placebo on body composition and function in older obese women. Women (63.8±3.4 yrs, BMI 32.9±4.1 kg/m2) were prescribed an energy‐restricted diet (1500 kcal/d; 15, 65, 30% of energy from protein, CHO and fat, respectively) and randomly assigned to 2 × 25g/d of whey protein (PRO, n=8) or maltodextrin (CARB, n=7) supplementation. Measures included whole body FM and FFM with DXA; thigh muscle, subcutaneous (SUBQ), intermuscular and intramyocellular fat with MRI; knee extension and flexion strength with isokinetic dynamometry. PRO trended towards greater weight loss (−10.6±6.7%, −5.0±4.0%; p=0.078), had greater reductions in FM (−18.9±10.6%, −8.0±4.2%; p=0.024) than CARB, but no significant difference in FFM (−4.0±4.9%, −2.0±4.1%; p=0.414). %SUBQ thigh fat change (−6.1±3.0%, −1.3±1.7%; p=0.003) was the only significant MRI outcome. Groups did not differ in leg strength changes. Higher protein intake in weight loss in older women enhances FM reductions while preserving FFM; however, these changes do not impact changes in physical function.Grant Funding Source: National Dairy Council, Carraway Foundation

High dietary calcium does not mediate the effects of dairy to attenuate weight gain and improve glucose tolerance in mice with pre‐existing obesity

Previous research in animal models suggests increased dietary Ca and dairy reduces weight gain and obesity‐associated inflammation. Effects of these dietary factors on obese phenotypes when introduced in the context of pre‐existing obesity are less clear. We investigated the effects of introducing high calcium (HC) and HC with non‐fat dry milk (NFDM) in adult male C57BL/6J mice pre‐fattened with an obesigenic, pro‐inflammatory high fat diet (45% kcal; HFD) for 12 wks. Mice were then assigned (n=30/group) to one of three macronutrient‐matched HF diets for an additional 8 wks: control (0.5%; CON), HC (1.5% Ca), or HC with NFDM. Surprisingly, HC mice gained more wt (10.1 + 0.5 g vs. 5.3 + 0.4 g; P&lt;0.001) with a significantly higher feed efficiency (12.8 + 0.5 mg wt gain/kcal intake) and decreased glucose tolerance (GT) compared to CON. NFDM mice gained the least wt (2.2 + 0.6g; P&lt;0.001) with a lower feed efficiency (3.0 + 0.6 vs. 7.8 + 0.4 mg wt gain/kcal intake) and improved GT vs. CON. Obesity‐related inflammatory markers are currently being analyzed. We conclude that effects of dairy to reduce weight gain and improve glucose tolerance in mice with pre‐existing obesity and fed a HFD is not mediated by dietary Ca, and likely results from other factors specific to the NFDM diet.Grant Funding Source: National Dairy Council and ARS Project 5306–51530–016–00D

Vitamin D Status in Overweight and Obese Individuals During A Controlled Calorie Restricted Intervention

Vitamin D deficiency is common in obese subjects and status may be improved with dietary interventions. We examined serum 25(OH)D in overweight and obese individuals enrolled in a controlled calorie restricted intervention. Serum samples from overweight and obese (BMI = 28–37) subjects (F=53, M=18), participating in a study examining dairy's role in weight and fat loss, were taken pre‐ and post‐intervention. Participants were randomly assigned to either a high dairy (HD: 3–4 servings; average 333IU D) or low dairy (LD: ≤ 1 serving/d, average 151 IU D) for 12 wks. Energy balance was achieved in wks 1–3 followed by 12wk of 500 kcal/d reduction. All foods were supplied by the metabolic food lab. Outcome variables were body weight (WT), body fat (BF) determined by DXA and serum 25(OH)D measured by RIA. When controlling for total body fat mass, ANOVA showed a significant treatment effect with a greater increase in the %change of serum 25(OH)D in the high dairy group (27.27 ± 37.47 nmol; p = 0.05) compared to the low dairy group(13.16 ± 32.7 nmol; p = .09). The inclusion of 3–4 servings of vitamin D fortified dairy rich foods in a moderate energy restricted diet may contribute to an improved vitamin D status in overweight and obese individuals.Funding: National Dairy Council; USDA, ARS, WHNRC; DairyCouncil of California; CTSC, CCRC University of California (1M01RR19975‐01), and National Center for Medical Research (UL1 RR024146).

Higher protein weight loss diet does not affect bone mineral density (BMD) in a double‐blind RCT in postmenopausal women

In spite of longstanding theory that protein intakes above the RDA are harmful to bone, clinical trials have variably shown no influence or protection of bone with higher protein intakes during weight loss. Studies to date have failed to match intakes of calcium and vitamin D, leaving the independent effect of protein ambiguous.We prescribed a conventional, MyPyramid‐based energy restricted diet (1500 kcal/d) to 31 postmenopausal women (age 65±5y, BMI 33.8±4.9), then randomly assigned 50g/d of supplemental maltodextrin (CARB) or whey protein isolate (PRO) to be added as 25g doses to breakfast and lunch, for 0.8g/kg total protein in CARB and 1.4g/kg in PRO groups. All women received 1g Calcium and 800 IU Vitamin D as a daily multivitamin.After 6 mo, women lost (PRO, CARB) 9.8±6.7, 4.8±3.7% of baseline weight (p=0.06). Bone mineral density changed 2.4, 2.1% (p=0.70) for whole body, −0.8, 1.4% (p=0.13) for lumbar spine and −0.4 and −0.2% (p=0.84) for total hip.This double blind, randomized, controlled trial supports growing consensus that higher protein intakes are not harmful to bone in the context of adequate calcium and vitamin D intakes.Support: National Dairy Council &amp; Carraway Foundation

Contributions of milk, dairy products, and other foods to vitamin D intakes in the U.S.: NHANES, 2003–2006

Many Americans have vitamin D intakes below the Adequate Intake level. This study examined food sources of vitamin D using NHANES, 2003–2006, data and the recently released Vitamin D Addendum to USDA Food and Nutrient Database for Dietary Studies 3.0. Vitamin D intakes were determined for all subjects 2 yrs and older with complete, reliable 24‐hr recall interviews on Day 1 (n=16,822). With food mixtures/mixed dishes classified by their main ingredient, the percent contributions to vitamin D intake from dairy products; grain products; meat, poultry, and fish; eggs, legumes, nuts and seeds; fruits and fruit juices; vegetables; and other foods was, 68.1,12.7, 9.2, 3.0, 3.0, 0.6, and 3.5%, in children 2–18 yrs (n=7,332), and 46.0, 10.7, 23.4, 5.7, 3.6, 1.4, and 9.1% in adults 19+ yrs (n=9,490), respectively. Using current food composition data, fluid milk/milk drinks provided 49.7, 65.8, and 43.2% of vitamin D intake in all subjects 2+ yrs, children 2–18 yrs and adults 19+ yrs, respectively. While still the primary source, a lower percent of daily vitamin D was provided by milk/milk drinks in Non‐Hispanic Black as compared to Non‐Hispanic White and Mexican American subjects (2–18 yrs: 57.0 vs. 67.9 and 65.1 %, respectively; and 19+ yrs: 28.7 vs. 45.3 and 48.5%, respectively). In conclusion, milk and milk products are the primary sources of vitamin D from food in the U.S. diet. (Supported by the National Dairy Council)

Food sources of calcium, phosphorus, vitamin D, and potassium in the U.S.

Dietary food patterns recommended for children and adults include two/three daily servings of dairy foods to provide important bone building nutrients, namely calcium (Ca), phosphorus (P), and vitamin D and contribute to potassium (K) intakes. The aim of this study was to determine dietary sources of Ca, P, vitamin D, and K in the U.S. using NHANES, 2003–2006 data. Intakes were determined for subjects, 2+ yrs (n=16,822) with a reliable 24‐hr recall interview on the first day. With food mixtures/mixed dishes classified by their main ingredient, the top five food categories as sources (%) of Ca were dairy (38.6), grains (28.8), beverages (7.2), sweets and desserts (7.2), and meat, poultry and fish (4.5); of P were grains (28.6), dairy (22.0), meat, poultry and fish (21.0), sweets and desserts (6.7), and eggs, legumes and nuts (6.4); of vitamin D were dairy (52.3), meat, poultry and fish (19.3), grains (11.3), eggs, legumes and nuts (4.9), and fruit/fruit juice (3.4); and of K were grains (20.3), meat, poultry and fish (16.2), dairy (13.9), vegetables (13.7), and fruit/fruit juice (11.1). Fluid milk was the number one single food source of Ca, P, vitamin D, and K providing 21.5, 12.3, 42.6, and 9.9%, respectively, of the total dietary intake of these nutrients. In conclusion, these data continue to support that dairy products and fluid milk, in particular, are the major sources of important nutrients from food in the U.S. diet. (Supported by the National Dairy Council)

Leucine contents of isonitrogenous protein sources predict changes in body composition and muscle mass in rats

Increases in intracellular leucine (leu) concentrations stimulate mTOR phosphorylation regulation of skeletal muscle protein synthesis (MPS) and leu content of isonitrogenous complete meals predict MPS potential of individual proteins (J Nutr 139:1103–9, 2009). While the molecular mechanism is established, direct effect of leu on long‐term changes in muscle weight or body composition are unknown. This study evaluated 4 isonitrogenous, isoenergtic diets containing wheat (supplemented with lys), soy, egg, or whey with 6.8, 8.0, 8.8, and 10.9% leu respectively, to determine meal effects of leu on signaling and MPS and long‐term impact on body composition. Male rats (275g) were fed 3 meals/d for 76d consisting of 16/54/30% of energy from protein, carbohydrates and fats. Blood and tissue were taken before or 90min after the breakfast meal at wk 2 and 11. Measurements included muscle weights, body composition by DXA, MPS by D5‐Phe incorporation, and phosphorylation of initiation factors 4E‐BP1 and S6K. Leu content of the meals increased muscle weights and was inversely correlated with bodyfat and these outcomes were associated with greater phosphorylation of 4E‐BP1 and S6K and MPS in animals fed egg and whey. These findings establish that leu content is a crucial factor defining the quality of proteins influencing muscle mass and body composition in adults. Supported by National Dairy Council and Egg Nutrition Center.Grant Funding Source: National Dairy and Egg Nutrition Center

Resistance training improves the inflammatory response to an acute resistance exercise bout in healthy young adults

Ten non‐resistance trained subjects (8 men, 2 women, 21–28 y) participated in a 9 mo supervised resistance exercise training 3 times/wk. We examined the inflammatory response to: 1) an acute resistance exercise bout (ARET) and 2) a 9 mo resistance training program by comparing the responses at baseline (T0) and after 9 months (T9). The ARET consisted of 6 × 10 repetitions of squats (75% of 1RM) with 2 min rest between sets. Blood was drawn pre‐ exercise, immediately post, 15 and 60 min after the ARET. Plasma cytokines were measured at all time points both at T0 and at T9. Analysis of the acute effects at T0 indicated that the proinflammatory cytokines interleukin (IL)‐1β, IL‐8 and tumor necrosis factor (TNF)‐α increased to a lesser extent than the anti‐inflammatory cytokines IL‐1ra and IL‐10 after 60 min. These results suggest that in spite of the large inflammatory response induced by ARET, this is counterbalanced by the body's anti‐inflammatory response in healthy subjects. When T0 and T9 were compared, the area under the curve for TNF‐α was significantly lower after training (T0=105.9 vs. T9=62.9 p=0.029) and it almost reached significance for IL‐15 (T0=26.5 vs T9=38.0 p=0.07). TNF‐α responses were diminished with training at 15m (T0=63.9.5 pg/mL vs T9=60.4 pg/mL p=0.035) and 60 m. (T0=79.7 pg/mL vs T9=34.8 pg/mL p=0.025). These reductions in TNF‐α indicate that resistance training reduces the inflammatory response to an acute bout of resistance training [Supported by the National Dairy Council]

How Does the DRI and Other Prediction Equations for Energy Intake Compare to Energy Fed?

Assessing energy needs is critical to dietary prescriptions for weight loss. We compared estimated calories from the Dietary Reference Intakes (DRI) equation and other accepted equations [Harris‐Benedict (HB) and Mifflin‐St.Jeor (MSJ)] to calories Fed in a controlled feeding study. Caloric needs were calculated for 79 overweight and obese (BMI: 27.5 – 37.5) women (n=56) and men (n=23) in a controlled feeding study. Calories were based on the DRI equation and adjusted during the controlled feeding period to maintain body weight (WT). WT was measured daily in the fasted state with clothing and without shoes. Calories were adjusted after 5 days of a consistent upward or downward slope in WT; further adjustments were made if body weight did not stabilize. WT stabilization was achieved in 21 days. Comparison between actual Fed calories and predicted calories from DRI, HB and MSJ equations are in Table 1. Fed DRI Harris‐Benedict Mifflin‐ St. Jeor Mean 2585.9 2580.2 2506.8 2384.0 STD 416.8 412.6 451.7 401.9 Significant correlations were observed among Fed calories and predicted calories for DRI (R2 = 0.97), HB (R2=0.85) and MSJ (R2 = 0.82). MSJ equation under estimated calories in 57% of people by −100 to −600 kcal/d. HB deviations in estimated calories ranged from +220 to −400 kcal/d in 49% of subjects. DRI estimated calories had the fewest deviations; 16.5% of subjects ranging from +200 kcal/d to −200 kcal/d.Funding: National Dairy Council, USDA, ARS, WHNRC, Dairy Council of California, CTS, Clinical Research Center, University of California (1M01RR19975‐01), and National Center for Medical Research (UL1 RR024146)