Sanjiv Agarwal

Effect of soy protein foods on low-density lipoprotein oxidation and ex vivo sex hormone receptor activity—A controlled crossover trial

Plant-derived estrogen analogs (phytoestrogens) may confer significant health advantages including cholesterol reduction, antioxidant activity, and possibly a reduced cancer risk. However, the concern has also been raised that phytoestrogens may be endocrine disrupters and major health hazards. We therefore assessed the effects of soy foods as a rich source of isoflavonoid phytoestrogens on LDL oxidation and sex hormone receptor activity. Thirty-one hyperlipidemic subjects underwent two 1-month low-fat metabolic diets in a randomized crossover study. The major differences between the test and control diets were an increase in soy protein foods (33 g/d soy protein) providing 86 mg isoflavones/2,000 kcal/d and a doubling of the soluble fiber intake. Fasting blood samples were obtained at the start and at weeks 2 and 4, with 24-hour urine collections at the end of each phase. Soy foods increased urinary isoflavone excretion on the test diet versus the control (3.8+/-0.7 v 0.0+/-0.0 mg/d, P < .001). The test diet decreased both oxidized LDL measured as conjugated dienes in the LDL fraction (56+/-3 v 63+/-3 micromol/L, P < .001) and the ratio of conjugated dienes to LDL cholesterol (15.0+/-1.0 v 15.7+/-0.9, P = .032), even in subjects already using vitamin E supplements (400 to 800 mg/d). No significant difference was detected in ex vivo sex hormone activity between urine samples from the test and control periods. In conclusion, consumption of high-isoflavone foods was associated with reduced levels of circulating oxidized LDL even in subjects taking vitamin E, with no evidence of increased urinary estrogenic activity. Soy consumption may reduce cardiovascular disease risk without increasing the risk for hormone-dependent cancers.

Combined effect of vegetable protein (soy) and soluble fiber added to a standard cholesterol-lowering diet☆

Dietary treatment of hyperlipidemia focuses on reducing saturated fat and dietary cholesterol. Other aspects of diet are not emphasized at present, despite growing evidence that a number of plant components decrease serum cholesterol. We therefore determined whether a combination of two plant components, vegetable protein and soluble fiber, further reduce serum lipids when incorporated into the currently advocated low-saturated-fat diet. Thirty-one hyperlipidemic men and women ate two 1-month low-fat (<7% of total energy from saturated fat), low-cholesterol (<80 mg cholesterol/d) metabolic diets in a randomized crossover study. The major differences between test and control diets were an increased amount of vegetable protein (93% v 23% of total protein), of which 33 g/d was soy, and a doubling of soluble fiber. Fasting blood samples were obtained at the start and end of each phase. On the last 3 days of each phase, fecal collections were obtained. Compared with the low-fat control diet, the test diet decreased total cholesterol (6.2% +/- 1.2%, P < .001), low-density lipoprotein (LDL) cholesterol (6.7% +/- 1.7%, P < .001), apolipoprotein B (8.2% +/- 1.2%, P < .001), and the ratios of LDL to high-density lipoprotein (HDL) cholesterol (6.3% +/- 2.0%, P = .004) and apolipoprotein B to A-I (5.4% +/- 1.5%, P = .001). A combination of vegetable protein and soluble fiber significantly improved the lipid-lowering effect of a low-saturated-fat diet. The results support expanding the current dietary advice to include increased vegetable protein and soluble fiber intake so that the gap in effectiveness between a good diet and drug therapy is reduced.

The effect of serum lipids and oxidized low-density lipoprotein of supplementing self-selected low-fat diets with soluble-fiber, soy, and vegetable protein foods

An increased intake of soluble fiber and soy protein may improve the blood lipid profile. To assess any additional benefit on serum lipids of providing soy protein and soluble-fiber foods to hyperlipidemic subjects already consuming low-fat, low-cholesterol therapeutic diets, 20 hyperlipidemic men and postmenopausal women completed 8-week test and control dietary treatments in a randomized crossover design as part of an ad libitum National Cholesterol Education Program (NCEP) step 2 therapeutic diet (<7% saturated fat and <200 mg/d cholesterol). During the test phase, foods high in soy, other vegetable proteins, and soluble fiber were provided. During the control phase, low-fat dairy and low-soluble-fiber foods were provided. Fasting blood lipid and apolipoprotein levels were measured at 4 and 8 weeks of each phase. On the test diet, 12 +/- 2 g/d soy protein was selected from the foods chosen. Direct comparison of test and control treatments indicated an elevated high-density lipoprotein (HDL) cholesterol concentration on the test diet (6.4% +/- 2.4%, P = .013) and a significantly reduced total to HDL cholesterol ratio (-5.9% +/- 2.3%, P = .020). The proportion of conjugated dienes in the low-density lipoprotein (LDL) cholesterol fraction was significantly reduced (8.5% +/- 3.3%, P = .020) as a marker of oxidized LDL. A combination of acceptable amounts of soy, vegetable protein, and soluble-fiber foods as part of a conventional low-fat, low-cholesterol therapeutic diet is effective in further reducing serum lipid risk factors for cardiovascular disease.

Solutions to obesity: perspectives from the food industry

Obesity has become an epidemic and an important public health concern. Because the problem is multidimensional, the solution will require an interdisciplinary approach involving the cooperation of the food industry with other stakeholders, such as the government, academia, and health care providers. The consumer is an important player in the solution to obesity because the consumer can make healthy lifestyle choices at the individual level. The food industry is committed to providing the consumer with healthy food options and reliable nutrition information.

Diets higher in animal and plant protein are associated with lower adiposity and do not impair kidney function in US adults

BACKGROUND Higher-protein diets are associated with decreased adiposity and greater HDL cholesterol than lower protein diets. Whether these benefits can be attributed to a specific protein source (i.e., nondairy animal, dairy, or plant) is unknown, and concerns remain regarding the impact of higher-protein diets on kidney function. OBJECTIVE The objective of this study was to evaluate trends of protein source on markers of cardiometabolic disease risk and kidney function in US adults. DESIGN Total, nondairy animal, dairy, and plant protein intake were estimated with the use of 24-h recall data from NHANES 2007-2010 (n = 11,111; ≥19 y). Associations between source-specific protein intake and health outcomes were determined with the use of models that adjusted for sex, race and ethnicity, age, physical activity, poverty-to-income ratio, individual intake (grams per kilogram) for each of the other 2 protein sources, body mass index (BMI) (except for weight-related variables), and macronutrient (carbohydrate, fiber, and total and saturated fat) intake. RESULTS Mean ± SE total protein intake was 82.3 ± 0.8 g/d (animal: 37.4 ± 0.5 g/d; plant: 24.7 ± 0.3 g/d; and dairy: 13.4 ± 0.3 g/d). Both BMI and waist circumference were inversely associated [regression coefficient (95% CI)] with animal [-0.199 (-0.265, -0.134), P < 0.0001; -0.505 (-0.641, -0.370), P < 0.0001] and plant [-0.346 (-0.455, -0.237), P < 0.0001; -0.826 (-1.114, -0.538), P < 0.0001] protein intake. Blood urea nitrogen concentrations increased across deciles for animal [0.313 (0.248, 0.379), P < 0.0001; decile 1-10: 11.6 ± 0.2 to 14.9 ± 0.3 mg/dL] and dairy [0.195 (0.139, 0.251), P < 0.0001; decile 1-10: 12.7 ± 0.2 to 13.9 ± 0.2 mg/dL] but not plant protein intake. Glomerular filtration rate and blood creatinine were not associated with intake of any protein source. CONCLUSIONS Diets higher in plant and animal protein, independent of other dietary factors, are associated with cardiometabolic benefits, particularly improved central adiposity, with no apparent impairment of kidney function.

Popcorn Consumption and Dietary and Physiological Parameters of US Children and Adults: Analysis of the National Health and Nutrition Examination Survey (NHANES) 1999-2002 Dietary Survey Data

Popcorn is a whole-grain food/snack that is included among foods recommended in the 2005 Dietary Guidelines for Americans and MyPyramid to increase whole-grain consumption. The purpose of the present study was to use 1999-2002 National Health and Nutrition Examination Survey 24-hour dietary recall data to determine the average popcorn intake among Americans, and whether popcorn consumers exhibited different dietary intake patterns or physiological biomarkers of cardiovascular disease compared with popcorn non-consumers. Mean intake among consumers of popcorn was 38.8 g/day. Compared with non-consumers, popcorn consumers had approximately 250% higher (P<0.01) intake of whole grains (2.5 vs 0.70 servings/day) and approximately 22% higher (P<0.01) intake of fiber (18.1 vs 14.9 g/day). Small but significant differences (P<0.01) were also observed for intake of carbohydrate, magnesium (higher intake in popcorn consumers), protein, niacin, and folate (lower intake in popcorn consumers). In addition, popcorn consumers had a greater (P<0.01) intake of total grains and consumed fewer meat servings. Popcorn consumption was associated with increased intake of whole grains, dietary fiber, and certain other nutrients.

Moderate doses of commercial preparations of Ginkgo biloba do not alter markers of liver function but moderate alcohol intake does: A new approach to identify and quantify biomarkers of ‘adverse effects’ of dietary supplements

Abstract It is difficult to determine if certain dietary supplements are safe for human consumption. Extracts of leaves of Ginkgo biloba trees are dietary supplements used for various purported therapeutic benefits. However, recent studies reported they increased risk of liver cancer in rodents. Therefore, this study assessed the association between ginkgo consumption and liver function using NHANES 2001–2012 data (N = 29,684). Since alcohol is known to adversely affect liver function, association of its consumption with liver function was also assessed. Alcohol and ginkgo extract intake of adult consumers and clinical markers of liver function (alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, gamma glutamyl transferase, lactate dehydrogenase, bilirubin) were examined. Moderate consumers of alcohol (0.80 ± 0.02 drinks/day) had higher levels of aspartate aminotransferase and gamma glutamyl transferase than non‐consumers (P < 0.001). There was no difference (P > 0.01) in levels of markers of liver function in 616 ginkgo consumers (65.1 ± 4.4 mg/day intake) compared to non‐consumers. While moderate alcohol consumption was associated with changes in markers of liver function, ginkgo intake as typically consumed by U.S. adults was not associated with these markers. Biomarkers measured by NHANES may be useful to examine potential adverse effects of dietary supplements for which insufficient human adverse event and toxicity data are available. Trial registration number Not applicable, as this is secondary analysis of publicly released observational data (NHANES 2001–2012). HighlightsGinkgo biloba extract was recently reported to cause liver cancer in animals.Associations between ginkgo consumption & liver function were evaluated using NHANES.Effects of alcohol intake on liver function were also examined as a positive control.Moderate intake of ginkgo did not alter liver function markers but alcohol did.NHANES can be used to examine potential adverse events of dietary supplements.

Establishing Pediatric and Adult RBC Reference Intervals With NHANES Data Using Piecewise Regression

Abstract Objectives To develop age- and sex-specific RBC reference intervals using the National Health and Nutrition Examination Survey (NHANES) 1999 to 2012, a large nationally representative, population-based, cross-sectional database (n = 44,328). Methods Comprehensive medical data were used to define a “healthy” population. Reference intervals for RBC count, hemoglobin, hematocrit, mean cell hemoglobin, mean cell hemoglobin concentration, mean cell volume, and red cell distribution width were computed using piecewise regression, an evidence-based statistical procedure that identifies breakpoints. Results The derived reference intervals were sex specific, unlike many current standards, and more precise for individuals of different ages, especially for children, adolescents, and elderly individuals, as additional breakpoints were detected for these groups. Suggested reference values for hematocrit and hemoglobin of older adult males were substantially lower than current values. Conclusions The reference intervals provided here, based on a large, nationally representative healthy population, contribute to the ongoing transition to precision medicine.