Human Nutrition Research Research Articles

Metabolic Adaptations to Weight Loss: Relative Changes in Resting Metabolic Rate and Energy Expenditure for Physical Activity and Association With Weight Loss Maintenance

Abstract Objectives There is persistent controversy over the extent to which different components of energy expenditure disproportionately decrease after weight loss and contribute to weight regain through decreased energy requirements. We conducted a secondary analysis of the CALERIE I study to test the hypothesis that decreased resting metabolic rate (RMR) and energy expenditure for physical activity (EEPA) after a 6-month calorie restriction intervention would predict weight regain at 12 months, with a greater decrease in RMR than EEPA. Methods Participants (n = 46) received all food and energy-containing beverages for 6 months. Outcome measures included total energy expenditure by doubly labeled water, RMR by indirect calorimetry, and body composition by BOD POD. Predictions for RMR and EEPA were derived from baseline linear regression models including age, sex, fat mass, and fat free mass. Baseline regression coefficients were used to calculate the predicted RMR and EEPA at 6 months. Residuals were calculated as the difference between measured and predicted values and were adjusted for body weight. The presence of metabolic adaptation was evaluated by a paired t-test comparing measured and predicted RMR at 6 months. Differences between 6-month RMR and EEPA residuals were evaluated by the same method. Linear regression was used to assess the association between 6-month residuals and weight loss maintenance (% weight change, 6 to 12 months). Results Mean weight loss was 6.9% at 6 months with 2.1% regain from 6 to 12 months. No adaptation in RMR was observed at 6 months (mean residual: 19 kcal; 95% confidence interval: −9, 48; P = 0.18). However, significant adaptation was observed in EEPA (mean residual: −199 kcal; −126, −272; P < 0.0001). In addition, the mean 6-month RMR residual was significantly greater than the mean 6-month EEPA residual (218 kcal; 133, 304; P < 0.0001). There was no significant association between 6-month RMR or EEPA residuals and weight regain at 12 months (P = 0.56, 0.34). Conclusions There was no measurable decrease in RMR with weight loss after adjusting for changes in fat free mass and fat mass, but there was a decrease in EEPA. Changes in RMR and EEPA with weight loss over 6 months did not predict weight regain at 12 months. Funding Sources Jean Mayer USDA Human Nutrition Research Center on Aging Doctoral Scholarship; USDA agreement #8050–51000-105–01S

Expression of CD25 in Individuals With Obesity With or Without Insulin Resistance After Following a North American Diet

ObjectivesObesity and insulin resistance (IR) are associated with systemic inflammation, lower immune function, and a higher risk of infection. We previously reported that individuals with obesity and type 2 diabetes have an impaired T cell response (i.e., lower IL-2 production, a marker of proliferation) upon T cell stimulation despite having more activated T cells compared to normoglycemic (NG) individuals with obesity. It remains unclear if the immune dysfunction is caused by adiposity, hyperglycemia and/or dietary patterns. The aim of this study was to investigate the effect of consuming an isocaloric North American-type diet on the IL-2 receptor (CD25) expression and cardiometabolic risk factors in lean, obese-NG, and obese-IR individuals. MethodsThis is a three parallel-arm trial in controlled feeding conditions being conducted at the Human Nutrition Research Unit, at the University of Alberta. Three groups of adults: Lean-NG (n = 7), Obese-NG (n = 8), and Obese-IR (n = 9) consumed an isocaloric standardized diet containing 35% fat, 48% carbohydrate, and 17% protein for 4 weeks. All meals were provided to participants. Blood samples were collected in the fasting state before and after the intervention and cardiometabolic risk factors were measured. Peripheral blood mononuclear cells (PBMCs) were isolated and the proportion of total immune cells expressing CD25 was determined by flow cytometry. ResultsAt baseline and post-intervention, Obese-IR had higher levels of glucose, insulin, and HOMA-IR and lower levels of HDL-C compared to both Lean-NG and Obese-NG groups (P < 0.05). At baseline, the proportion of PBMCs expressing CD25 tended to be lower in the Lean-NG (17.6 ± 2.7) compared to both Obese-NG (23.3 ± 4.8) and Obese-IR (23.2 ± 4.8) (P = 0.08). Post-intervention, the expression of CD25 was reduced in Lean-NG and Obese-IR groups (P < 0.01) but similar trends were still observed among all groups (P = 0.07). ConclusionsOur preliminary data suggest that obesity, independent of IR, is associated with greater activation of immune cells and consuming a North American-type diet lowers the expression of the IL-2 receptor in individuals with and without obesity. Therefore, both excess adiposity and dietary pattern appear to modulate the function of immune cells in obesity. Funding SourcesCanadian Institutes of Health Research.

Calcium Intake and Iron Status in Human Studies: A Systematic Review and Dose-Response Meta-Analysis of Randomized Trials and Crossover Studies

BackgroundThe interaction between dietary (and supplementary) divalent ions has been a long-standing issue in human nutrition research. Developing an optimal calcium and iron supplementation recommendation requires detailed knowledge of the potential trade-offs between: 1) the clinical effects of concurrent intake on iron absorption and hematological indices; and 2) the potentially negative effects of separated ingestion on adherence to iron and/or calcium supplements. Human clinical studies have examined the effects of calcium intake on iron status, but there are no meta-analyses or recent reviews summarizing the findings. ObjectivesTo synthesize peer-reviewed, human, randomized, and cross-over studies on effects of calcium consumption on iron indices without age, gender, or any other restrictions. MethodsWeighted mean differences for total, heme, and nonheme iron absorption (%) and serum ferritin (μg/L) were obtained from pooled analysis of the highest daily calcium intake compared to the lowest daily calcium intake. ResultsThe negative effect of calcium intake was statistically significant in short-term iron absorption studies, but the effect magnitude was low [weighted mean difference (WMD) = −5.57%; 95% CI: −7.09 to −4.04]. The effect of calcium on the iron status was mixed. The inverse dose-response association of calcium intake with the serum ferritin concentration was significant (P value = 0.0004). There was, however, no reduction in the hemoglobin concentration (WMD = 1.22g/L; 95% CI: 0.37–2.07). ConclusionsThe existing body of studies is insufficient to make recommendations with high confidence due to heterogeneity in designs, limitations of ferritin as an iron biomarker, and a lack of intake studies in pregnant women. Prescribing separation of prenatal calcium and iron supplements in free-living individuals is unlikely to affect the anemia burden. There is a need for effectiveness trials comparing the effects of prescribing separated intake to concurrent intake, with functional endpoints as primary outcomes and adherence to each supplement as intermediate outcomes.

Perspective: Laboratory Considerations and Clinical Data Management for Human Nutrition Randomized Controlled Trials: Guidance for Ensuring Quality and Integrity

ABSTRACTIn human nutrition randomized controlled trials (RCTs), planning, and careful execution of clinical data collection and management are vital for producing valid and reliable results. In this article, we provide an overview of best practices for biospecimen collection and analyses, and for the fundamentals of clinical data management, including preparation and study startup; data collection, entry, cleaning, and authentication; and database lock. The reader is also referred to additional resources for information to assist in the planning and conduct of human RCTs. The tools and strategies described are expected to improve the quality of data produced in human nutrition research that can, therefore, be used to support food and nutrition policies.

Perspective: Guidelines Needed for the Conduct of Human Nutrition Randomized Controlled Trials

ABSTRACTGuidelines for designing, conducting, documenting, and reporting human nutrition randomized controlled trials (RCTs) have as yet to be developed and disseminated as reference for investigators, funders, regulators, institutions, assessors, trainees, and others involved in human nutrition research. Diet-related interventions can include diet and/or behavioral manipulation, provision of foods or entire meals, or delivery of dietary components in individual food items or supplements. This Perspective introduces a series of papers that outline core principles for the design and conduct of human nutrition RCTs, documentation and reporting of all aspects of clinical trial management, and data analysis and reporting of results. Human nutrition RCTs have unique considerations delineated in these papers. Conducting them with the highest scientific rigor is essential to the development of evidence-based dietary guidance for promoting optimal health and advancing health care.

Perspective: US Documentation and Regulation of Human Nutrition Randomized Controlled Trials

ABSTRACTTraining to ensure good documentation practices and adherence to regulatory requirements in human nutrition randomized controlled trials has not been given sufficient attention. Furthermore, it is difficult to find this information conveniently organized or in a form relevant to nutrition protocols. Current gaps in training and research surveillance exist in clinical nutrition research because training modules emphasize drugs and devices, promote reliance on monitoring boards, and lack nutrition expertise on human nutrition research teams. Additionally, because eating is essential, ongoing, and highly individualized, it is difficult to distinguish risks associated with interventions from eating under free-living conditions. Controlled-feeding trials provide an option to gain more experimental control over food consumed, but at a price of less external validity, and may pose human behavior issues that are unrelated to the intervention. This paper covers many of the expected practices for documentation and regulation that may be encountered in planning and conducting nutrition intervention trials with examples and references that should be useful to clinical nutrition researchers, funders of research, and research institutions. Included are definitions and guidance on clinical nutrition research oversight (institutional review boards, data safety and monitoring boards, US FDA); participant safety; standard operating procedures; training of investigators, staff, and students; and local culture and reporting requirements relevant to diet-related clinical research conduct and documentation.

Preanalytical Sample Handling Conditions and Their Effects on the Human Serum Metabolome in Epidemiologic Studies

Many epidemiologic studies use metabolomics for discovery-based research. The degree to which sample handling may influence findings, however, is poorly understood. In 2016, serum samples from 13 volunteers from the US Department of Agriculture's Beltsville Human Nutrition Research Center were subjected to different clotting (30 minutes/120 minutes) and refrigeration (0 minutes/24 hours) conditions, as well as different numbers (0/1/4) and temperatures (ice/refrigerator/room temperature) of thaws. The median absolute percent difference (APD) between metabolite levels and correlations between levels across conditions were estimated for 628 metabolites. The potential for handling artifacts to induce false-positive associations was estimated using variable hypothetical scenarios in which 1%-100% of case samples had different handling than control samples. All handling conditions influenced metabolite levels. Across metabolites, the median APD when extending clotting time was 9.08%. When increasing the number of thaws from 0 to 4, the median APD was 10.05% for ice and 5.54% for room temperature. Metabolite levels were correlated highly across conditions (all r's ≥0.84), indicating that relative ranks were preserved. However, if handling varied even modestly by case status, our hypotheticals showed that results can be biased and can result in false-positive findings. Sample handling affects levels of metabolites, and special care should be taken to minimize effects. Shorter room-temperature thaws should be preferred over longer ice thaws, and handling should be meticulously matched by case status.

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Report of a member-led meeting: how stable isotope techniques can enhance human nutrition research.

A Nutrition Society member-led meeting was held on 9 January 2020 at The University of Surrey, UK. Sixty people registered for the event, and all were invited to participate, either through chairing a session, presenting a '3 min lightning talk' or by presenting a poster. The meeting consisted of an introduction to the topic by Dr Barbara Fielding, with presentations from eight invited speakers. There were also eight lightning talks and a poster session. The meeting aimed to highlight recent research that has used stable isotope tracer techniques to understand human metabolism. Such studies have irrefutably shaped our current understanding of metabolism and yet remain a mystery to many. The meeting aimed to de-mystify their use in nutrition research.

Effect of Whey Protein on Insulin Sensitivity and Glucose Metabolism in Women with and Without Polycystic Ovary Syndrome (PCOS)

Abstract Objectives This study focuses on the metabolic effects of whey protein isolate (WPI) supplementation glucose and insulin metabolism in women with and without Polycystic Ovary Syndrome (PCOS). Affecting up to 20% of post-puberty aged females around the world, PCOS is identified by three main symptoms: increased levels of androgens, irregular cycles, and the presence of ovarian cysts. Women with PCOS tend to be insulin resistant and have faulty insulin signaling. We hypothesize that because WPI has been seen to increase insulin sensitivity in type 2 diabetic populations, it will attenuate blood glucose and insulin levels and in women with PCOS. Methods 15 women with PCOS and 14 women without PCOS (CON) underwent four 150-min oral glucose tolerance tests (OGTT): (i) baseline (no protein), (ii) Day 20 (iii) and Day 40 of WPI preload. Daily, participants consumed 35 g WPI 30 min before glucose load on test days. Plasma levels of glucose and insulin were assessed using a Biolis 24i chemistry analyzer. Additionally, variations in gene expression levels of glucose metabolism regulators, e.g., GLUT-4, were analyzed in 3T3-L1 cells under normal and PCOS-simulated conditions using qt-PCR before and after WPI supplementation. Results At baseline, both PCOS and CON women had similar fasting glucose levels (107.2 ± 19.54 and 101.14 ± 11.03 respectively). After 20 days of WPI supplementation, fasting glucose increased (103.75 ± 0.5 and 117.25 ± 9.60) but was attenuated by Day 40 (91.5 ± 0.71 and 94.5 ± 0.71). Furthermore, the baseline levels of GLUT-4 expression between women with PCOS (2.698 ± 0.145) and CON (2.188, ± 0.062) were not statistically different. Levels of gene expression post-supplementation with WPI are in the process of being measured. And lastly, plasma insulin levels are in the progress of being measured for both populations before and after supplementation. Conclusions Preliminary analysis indicates that upon WPI supplementation, both groups glucose levels increased after 20 days, but was then attenuated by Day 40, with a slightly greater effect in the PCOS group compared to CON. Overall, our data indicates that WPI may be a potential dietary approach to better managing the symptoms of PCOS. Funding Sources Glanbia Nutritionals, Human Nutrition Research Funds, and Texas Woman's University.

Trimethylamine-N-Oxide (TMAO) Is Not Associated with Average Daily Intake of Red Meat or TMAO-Precursor Foods in a Generally Healthy Population

Abstract Objectives The microbial metabolite trimethylamine n-oxide (TMAO) is associated with cardiovascular and renal disease. The dietary factors contributing to plasma TMAO concentrations are not well characterized in a generally healthy population unmedicated for metabolic diseases. The objective of this study was to assess the relationships among TMAO-precursor foods, TMAO, and classic cardiometabolic markers in a generally healthy population stratified for age, sex, and BMI. Methods Fasting plasma TMAO was quantified using liquid chromatography-mass spectrometry in 356 participants (n = 188 female, 18–65 yr, 18–40 BMI) enrolled in the cross-sectional Nutritional Phenotyping Study conducted as the USDA Western Human Nutrition Center. Diet was assessed by averaging 2 weekday and 1 weekend ASA-24hr recalls cleaned by NCBI guidelines. Fasting plasma analytes such as glucose, insulin, triglycerides, and cholesterol were measured using the Cobas Integra 400 Plus. Variables were transformed to conform to the normal distribution. Regression models assessing health parameters and TMAO were adjusted for age, sex, and the kidney function marker, cystatin C. Models assessing TMAO and diet variables were adjusted for age, sex, and energy intake. Composite variables describing average intake of red meat and TMAO-precursor foods were created by summing the appropriate ASA24 variables. Results TMAO was associated with age (P = 0.001), but not sex or BMI. A significant interaction (P = 0.006) between sex and age was used in all models. Of the variables analyzed, only refined grains and total energy intake were significantly associated with TMAO (r = −0.11, P = 0.04; r = 0.12, P = 0.03, respectively). Reduced renal function as assessed by circulating cystatin C concentrations was associated with plasma TMAO (r = 0.18, P &amp;lt; 0.001). Average daily red meat consumption as well as average daily TMAO-precursor consumption was not significantly associated with TMAO (P = 0.137, P = 0.554, respectively). In contrast, average daily fiber intake was marginally related to TMAO (B = −0.11, SE = 0.01, P = 0.07). Conclusions In this generally healthy population, no relationship between red meat or TMAO-precursor foods and TMAO was identified. Funding Sources The Beef Checkoff (R01HL128572); USDA/ARS/Western Human Nutrition Research Center project funds (2032–51,000-025–00D).

No Effect of the Dietary Inflammatory Index on Psychological Health During Caloric Restriction: A Secondary Analysis of the CALERIE Trial Data

Abstract Objectives Anti-inflammatory diets have been suggested to improve psychological health. This research evaluated the combined effects of consuming an anti-inflammatory diet and caloric restriction (CR) on changes in perceived stress and health-related quality of life in a healthy, non-obese population. Methods We conducted a secondary analysis of the publicly available CALERIE data. Participants were randomized to a 2 year CR intervention (n = 143) or an ad libitum Control group (n = 75) and self-selected their dietary intake. An energy-adjusted dietary inflammatory index (DII) was calculated based on 28 components from self-reported food records. Self-reported stress and general health outcomes were measured using validated questionnaires. Linear mixed models were used to assess changes in each outcome from baseline to 12 and 24 months. Models were adjusted for age, sex, baseline outcome measure, change in body fat, and a treatment by DII interaction term. Results On average, participants were 38.1 ± 7.2 years old with a BMI of 25.1 ± 1.7 kg/m2. Baseline characteristics, including the DII, stress, and general health, did not differ with randomization. There was no significant association between temporal changes in DII and changes in stress or general health in the CR or Control groups. On average, both groups tended to report higher stress at 12 months; however, there was no difference in perceived stress between groups (adjusted mean difference [MD]: 0.5; 95% confidence interval [CI]: −0.4, 1.5; P = 0.25). There was an improvement in reported general health in the CR group at 12 months (MD: 4.1; 95% CI: 2.2, 6.0; P &amp;lt; 0.001), but not in Controls (MD: 1.6; 95% CI: −1.2, 4.3; P = 0.26). Yet self-reported general health was similar both groups (MD: 2.5; 95% CI: −1.3, 6.3; P = 0.16). The effect of a CR intervention on both outcomes did not differ with change in DII. Similar results were observed at 24 months. Conclusions There was no indication of any contribution of a low DII score on perceived stress and general health in the presence of CR. Additional research is required to enhance our understanding of the implications of dietary inflammation on a broad range of psychological health outcomes. Funding Sources Jean Mayer USDA Human Nutrition Research Center on Aging Doctoral Scholarship; USDA agreement #8050–51,000-105–01S.

Cholesterogenic Effects of Whey Protein Isolate Supplementation in Women with Polycystic Ovary Syndrome

Abstract Objectives The current study examined the short- and long-term effects of whey protein isolate ingestion on circulating Low-Density Lipoprotein (LDL) and total cholesterol (TC) concentrations in women with polycystic ovary syndrome (PCOS). PCOS is a disorder characterized by reproductive, metabolic and endocrine disruption in women of reproductive age. Nutritional management options are limited. Whey protein isolate (WPI) improves metabolic parameters in patients with type 2 diabetes, but its therapeutic potential in polycystic women has yet to be realized. Women with PCOS have altered metabolic profiles and are more likely to develop liver disorders such as non-alcoholic fatty liver disease (NAFLD). Given the association between PCOS and NAFLD, we hypothesized that supplementation with WPI may attenuate circulating LDL and TC in a polycystic population. Methods Fifteen premenopausal women with PCOS and fourteen healthy, regularly menstruating women underwent three 150-min oral glucose tolerance tests (OGTT): (i) OGTT without protein preload, (ii) OGTT on 20th, and (iii) 40th day of protein preload. Participants consumed 35g protein daily with protein intake 30 min before carbohydrate load on test days. Plasma levels of LDL and total cholesterol were assessed at baseline, day 20 and day 40 to determine short- and long-term effects using a Biolis 24i chemistry analyzer. (Participant recruitment, data collection and analyses in progress.) Results Preliminary data indicates that time and condition (PCOS vs control) did not have a significant effect on LDL or TC levels within and between groups (P &amp;gt; .05). However, disease condition had a significant impact on LDL (P &amp;lt; .001) and TC (P = .001) concentrations. Changes in LDL and TC levels after 40 days of protein preload are currently being analyzed. Conclusions Women with PCOS have higher levels of LDL and TC than those without this condition. While short-term effects of 35g WPI ingestion do not seem to alter these levels, a longer duration of supplementation may induce more beneficial effects (currently being conducted). Findings from this study may provide foundational support for WPI as a nutritional treatment for women with PCOS. Funding Sources Glanbia Nutritionals, INC and Human Nutrition Research Funds, Texas Woman's University.

Effects of Whey Protein Supplementation on Body Composition and Vascular Health in Women with Polycystic Ovarian Syndrome

Abstract Objectives Polycystic Ovarian Syndrome (PCOS) is the most common female endocrine disorder and a leading cause of female infertility in the US. In addition, PCOS women have an increased risk of developing type 2 diabetes (T2DM), hypertension (HTN) and heart disease. One of the most significant factors associated with HTN is increased circulating angiotensin II (Ang II). Metabolites generated as result of whey protein digestion improve insulin sensitivity, inhibit ACE (an enzyme responsible for production of Ang II) thereby playing an important role in the prevention of HTN and associated cardio-vascular pathologies. These benefits of whey protein ingestion have been demonstrated in normal populations and in individuals with T2DM.The purpose of this study was to examine changes in blood pressure (BP), Ang II and Adiponectin concentrations following 40 days of whey protein supplementation and to examine differences in baseline measurements of between body fat distribution in PCOS women and healthy controls (CON). Methods Women with PCOS and CON consumed 35 g of whey protein for 40 days. Baseline, Day 20 and Day 40 concentrations were measured via plasma and serum collection. Resting BP (Systolic and Diastolic pressures; SBP and DBP respectively) were measured with an electronic monitor were used to calculate mean arterial pressure (MAP) at baseline, Day 20 and Day 40. DXA was used to estimate body composition and fat distribution (total body fat, trunk fat and Android: Gynoid fat ratio [A: G]) at baseline. Results Preliminary analyses indicates that at baseline SBP was significantly lower in the CON group compared to PCOS. However, DBP and MAP had no significant differences at baseline. The PCOS group also had lower adiponectin levels at baseline when compared to the CON group. Ang II concentrations, as well as Day 20 and Day 40 analysis are currently being evaluated. Conclusions Overall, our results indicate that vascular health is compromised in young women with PCOS compared to health controls. Results from this research, will not only help provide a better understanding of the link between inflammatory markers such as Ang II and the increased risk of HTN commonly seen in women with PCOS, but it also provide a nutritional intervention to help prevent these disorders. Funding Sources Glanbia Nutritionals, Inc., TWU Research Enhancement Program, TWU Human Nutrition Research funds.

Crop Varietal Mixtures as a Strategy to Support Insect Pest Control, Yield, Economic, and Nutritional Services

Most on-farm diversification strategies to enhance ecosystem services, such as insect pest control and yield, have focused on expanding crop species diversity. While polycultures often provide valuable services, logistical constraints with planting and harvesting can hamper implementation on large scales. An alternative diversification strategy is to increase within-field intraspecific crop diversity through the use of crop varietal mixtures. Here, we evaluate an interdisciplinary body of research to determine the potential for crop varietal mixtures to support food security by providing ecological, economic, and nutritional services. Previous literature has synthesized the link between varietal mixtures and yield and insect pest suppression services. We expand on prior analyses by considering hypotheses generated from species-level research and assessing whether they also provide a useful framework for predicting how varietal mixtures affect crop productivity and insect pest suppression. In addition, we evaluate the potential for varietal mixtures to increase farm resilience and growers’ profits. While there is a growing effort to quantify the economic value of ecosystem services provided by agrobiodiversity in terms of enhanced yield or revenue, much less attention has been given to quantifying the production costs associated with diversification schemes. Consequently, we know little about the effect of diversification practices on farm profitability, the metric of ultimate importance to farmers. We address this issue by evaluating the ability of varietal mixtures to reduce production costs associated with other types of agrobiodiversity and outline areas for future research to better understand the profit implications of varietal mixtures. Further, we review evidence that varieties of some crop species differ in phytochemical content—a functional trait important for insect pest suppression and human dietary diversity—suggesting that varietal mixtures could be designed to simultaneously support insect pest control and human nutrition services. Given that little research has explicitly addressed the capacity for varietal mixtures to support human nutrition, we outline predictions for where we would expect to see the greatest nutritional impact of mixtures, providing a foundation for future human nutrition research. Taken together, our review suggests that varietal mixtures are a promising and logistically feasible strategy that could simultaneously support multiple services.

Publisher Correction: Uncertainty in human nutrition research

Publisher Correction: Uncertainty in human nutrition research

Uncertainty in human nutrition research

Given the important role that nutritional science plays in global food and health policy, some of the key uncertainties in nutrition research that policy makers should take into consideration are outlined here.

Anti‐hypertensive Effects of Whey Protein Supplementation in Women with Polycystic Ovarian Syndrome

Polycystic Ovarian Syndrome (PCOS) is the most common female endocrine disorder and a leading cause of female infertility affecting about 5 million women of reproductive age in the US. It is characterized by metabolic dysfunction, abnormal hormonal pattern, hyperandrogenism, insulin resistance (IR), dyslipidemia and an inflammatory state. In addition, PCOS women have an increased risk of developing type 2 diabetes (T2DM), hypertension (HTN) and heart disease. One of the most significant factors associated with HTN is increased circulating angiotensin II (Ang II). Ang II is a pro‐inflammatory factor produced by adipose tissue and has been implicated in linking obesity, inflammation and IR. Metabolites generated as result of whey protein digestion improve insulin sensitivity, inhibit ACE (an enzyme responsible for production of Ang II) thereby playing an important role in the prevention of HTN and associated cardio‐vascular pathologies. These benefits of whey protein ingestion have been demonstrated in normal populations and in individuals with T2DM. The purpose of this study was to examine changes in blood pressure (BP), Ang II and Adiponectin concentrations following 40 days of whey protein supplementation and to examine differences in baseline measurements of between body fat distribution in PCOS women and healthy controls (CON). Women with PCOS and CON were recruited from Texas Woman’s University (TWU) and asked to consume 35g of whey protein for 40 days. Baseline, Day 20 and Day 40 concentrations were measured via plasma and serum collection. Resting BP (Systolic and Diastolic pressures; SBP and DBP respectively) were measured with an electronic monitor were used to calculate mean arterial pressure (MAP) at baseline, Day 20 and Day 40. DXA was used to estimate body composition and fat distribution (total body fat, trunk fat and Android: Gynoid fat ratio [A:G]) at baseline. Protocols used in this study were approved by TWU’s Institutional Review Board (IRB). Preliminary analyses indicates that at baseline SBP was significantly lower in the CON group compared to PCOS. However, DBP and MAP had no significant differences at baseline. The PCOS group also had lower adiponectin levels at baseline when compared to the CON group. Ang II concentrations, as well as Day 20 and Day 40 analysis are currently being evaluated. Overall, our results indicate that vascular health is compromised in young women with PCOS compared to health controls. Results from this research, will not only help provide a better understanding of the link between inflammatory markers such as Ang II and the increased risk of HTN commonly seen in women with PCOS, but it also provide a nutritional intervention to help prevent these disorders.Support or Funding InformationGlanbia Nutritionals, Inc., TWU Research Enhancement Program, TWU Human Nutrition Research funds.

Metabolic Effects of Whey Protein Isolate Supplementation on Cholesterol and Triglycerides in Women with Polycystic Ovary Syndrome

The current study examined the acute‐ and chronic effects of whey protein isolate ingestion on plasma cholesterol and triglyceride concentrations in women with polycystic ovary syndrome (PCOS). PCOS, an endocrine abnormality in women of reproductive age, is characterized by menstrual cycle disturbance, hyperandrogenism and obesity. Women with PCOS have altered metabolic profiles and are more likely to develop type 2 diabetes and/or liver disorders such as non‐alcoholic fatty liver disease (NAFLD). Nutritional management options are severely limited. Whey protein isolate (WPI) improves metabolic parameters in patients with and without type 2 diabetes, but its therapeutic potential in polycystic women has yet to be realized. Given the association between PCOS and NAFLD, we hypothesized that supplementation with WPI may attenuate circulating cholesterol and triglycerides in a polycystic population. Fifteen premenopausal women with PCOS and eleven healthy, regularly menstruating women underwent three 150‐min oral glucose tolerance tests (OGTT): (i) OGTT without protein preload, (ii) OGTT on 1st, and (iii) 40th day of protein preload. Participants consumed 35g protein daily with protein intake 30 min before carbohydrate load on test days. Plasma levels of cholesterol and triglycerides were assessed at baseline, day 1 and day 40 to determine acute and chronic effects on cholesterol and triglycerides using a Biolis 24i chemistry analyzer. (Participant recruitment, data collection and analyses in progress.) Protocols used in this study were approved by the TWU Institutional Review Board. Mixed Model Repeated Measure ANOVA indicates that time and condition (PCOS vs control) did not have a significant effect on cholesterol or triglyceride levels within and between groups (p &gt; .05). However, preliminary data indicate that disease condition had a significant impact on cholesterol (p&lt; .001) and triglyceride (p = .001) concentrations at baseline. Changes in cholesterol and triglyceride levels after 40 days of protein preload are currently being analyzed. Women with PCOS have higher levels of cholesterol and triglycreides than those without this condition. While acute effects of 35g WPI ingestion do not seem to alter these levels, a longer duration of supplementation may induce more beneficial effects (currently being conducted). Findings from this study will provide foundational support for WPI as a nutritional treatment for PCOS and reveal insights into cholesterol metabolism mechanisms that are affected by PCOS and NAFLD.Support or Funding InformationGlanbia Nutritionals, INC; Human Nutrition Research Funds, Texas Woman’s University; Research Enhancement Program, Texas Woman’s University

Effect of 7‐Day Whey Protein Supplementation on Steroid Hormones and SHBG in Women with Polycystic Ovary Syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is the most prevalent endocrinopathy in women of child‐bearing age and is associated with obesity, infertility, insulin resistance, and hyperandrogenemia. Sex‐hormone binding globulin (SHBG) is suppressed as a result of hyperinsulinemia leading to an increase in free testosterone levels commonly observed in PCOS women. High levels of free testosterone contributes to hirsutism, acne, and irregular menstrual cycles in this population resulting in the need for interventions aimed at increasing SHBG concentration in PCOS women. Subsequently, estradiol and progesterone levels suffer in this population resulting in irregular menstrual cycles and infertility. Current treatments for PCOS target symptoms of the disease but not the underlying mechanisms, and typically are associated with adverse side effects. Nutritional interventions, therefore, that can ameliorate PCOS‐related issues are warranted. Whey protein has recently been shown to have improved glycemic homeostasis, reduced chronic inflammation and enhanced protein anabolism effects in people with or without insulin resistance. The purpose of this study was to examine changes in SHBG and free testosterone concentrations following 7 days of whey protein supplementation and to examine differences in baseline measurements of progesterone and estradiol between PCOS women and healthy controls (CON). Women with PCOS and CON consumed 35g of whey protein for 7 days. Baseline and Day 7 concentrations were measured via plasma and serum collection. Progesterone and estradiol concentrations were measured at baseline only whereas free testosterone and SHBG concentrations were measured at baseline and Day 7. Protocols used in this study were approved by the TWU Institutional Review Broad (IRB). Initial analyses indicate progesterone levels were lower in the PCOS group compared to CON. Currently, no other statistical differences are reported at baseline nor over time in any other variable. Additional analyses are currently being conducted. Seven days whey protein supplementation is not a viable intervention to increase fertility in PCOS women by enabling changes in steroid hormone and globulin binding concentrations. Future studies will include a prolonged intervention period to establish potential changes in the aforementioned hormones following chronic whey protein supplementation.Support or Funding InformationGlanbia Nutritionals, Inc., TWU Research Enhancement Program, TWU Human Nutrition Research funds