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The WHI joins MRFIT: a revealing look beneath the covers.

Am J Clin Nutr. 2010 Feb 24;

Authors: Willett WC

PMID: 20181816 [PubMed - as supplied by publisher]

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Establishing optimal selenium status: results of a randomized, double-blind, placebo-controlled trial.

Am J Clin Nutr. 2010 Feb 24;

Authors: Hurst R, Armah CN, Dainty JR, Hart DJ, Teucher B, Goldson AJ, Broadley MR, Motley AK, Fairweather-Tait SJ

BACKGROUND: Dietary recommendations for selenium differ between countries, mainly because of uncertainties over the definition of optimal selenium status. OBJECTIVE: The objective was to examine the dose-response relations for different forms of selenium. DESIGN: A randomized, double-blind, placebo-controlled dietary intervention was carried out in 119 healthy men and women aged 50-64 y living in the United Kingdom. Daily placebo or selenium-enriched yeast tablets containing 50, 100, or 200 mug Se ( approximately 60% selenomethionine), selenium-enriched onion meals ( approximately 66% gamma-glutamyl-methylselenocysteine, providing the equivalent of 50 mug Se/d), or unenriched onion meals were consumed for 12 wk. Changes in platelet glutathione peroxidase activity and in plasma selenium and selenoprotein P concentrations were measured. RESULTS: The mean baseline plasma selenium concentration for all subjects was 95.7 +/- 11.5 ng/mL, which increased significantly by 10 wk to steady state concentrations of 118.3 +/- 13.1, 152.0 +/- 24.3, and 177.4 +/- 26.3 ng/mL in those who consumed 50, 100, or 200 mug Se-yeast/d, respectively. Platelet glutathione peroxidase activity did not change significantly in response to either dose or form of selenium. Selenoprotein P increased significantly in all selenium intervention groups from an overall baseline mean of 4.99 +/- 0.80 mug/mL to 6.17 +/- 0.85, 6.73 +/- 1.01, 6.59 +/- 0.64, and 5.72 +/- 0.75 mug/mL in those who consumed 50, 100, or 200 mug Se-yeast/d and 50 mug Se-enriched onions/d, respectively. CONCLUSIONS: Plasma selenoprotein P is a useful biomarker of status in populations with relatively low selenium intakes because it responds to different dietary forms of selenium. To optimize the plasma selenoprotein P concentration in this study, 50 mug Se/d was required in addition to the habitual intake of approximately 55 mug/d. In the context of established relations between plasma selenium and risk of cancer and mortality, and recognizing the important functions of selenoprotein P, these results provide important evidence for deriving estimated average requirements for selenium in adults. This trial was registered at clinicaltrials.gov as NCT00279812.

PMID: 20181815 [PubMed - as supplied by publisher]

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Effects of coffee consumption on subclinical inflammation and other risk factors for type 2 diabetes: a clinical trial.

Am J Clin Nutr. 2010 Feb 24;

Authors: Kempf K, Herder C, Erlund I, Kolb H, Martin S, Carstensen M, Koenig W, Sundvall J, Bidel S, Kuha S, Tuomilehto J

BACKGROUND: Coffee consumption is associated with a decreased risk of type 2 diabetes. Suggested mechanisms underlying the association have included attenuation of subclinical inflammation and a reduction in oxidative stress. OBJECTIVE: The aim was to investigate the effects of daily coffee consumption on biomarkers of coffee intake, subclinical inflammation, oxidative stress, glucose, and lipid metabolism. DESIGN: Habitual coffee drinkers (n = 47) refrained for 1 mo from coffee drinking; in the second month they consumed 4 cups of filtered coffee/d and in the third month 8 cups of filtered coffee/d (150 mL/cup). Blood samples were analyzed by gas chromatography-mass spectrometry, bead-based multiplex technology, enzyme-linked immunosorbent assay, or immunonephelometry. RESULTS: Coffee consumption led to an increase in coffee-derived compounds, mainly serum caffeine, chlorogenic acid, and caffeic acid metabolites. Significant changes were also observed for serum concentrations of interleukin-18, 8-isoprostane, and adiponectin (medians: -8%, -16%, and 6%, respectively; consumption of 8 compared with 0 cups coffee/d). Serum concentrations of total cholesterol, HDL cholesterol, and apolipoprotein A-I increased significantly by 12%, 7%, and 4%, respectively, whereas the ratios of LDL to HDL cholesterol and of apolipoprotein B to apolipoprotein A-I decreased significantly by 8% and 9%, respectively (8 compared with 0 cups coffee/d). No changes were seen for markers of glucose metabolism in an oral-glucose-tolerance test. CONCLUSIONS: Coffee consumption appears to have beneficial effects on subclinical inflammation and HDL cholesterol, whereas no changes in glucose metabolism were found in our study. Furthermore, many coffee-derived methylxanthines and caffeic acid metabolites appear to be useful as biomarkers of coffee intake.

PMID: 20181814 [PubMed - as supplied by publisher]

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The Smart Choices front-of-package nutrition labeling program: rationale and development of the nutrition criteria.

Am J Clin Nutr. 2010 Feb 24;

Authors: Lupton JR, Balentine DA, Black RM, Hildwine R, Ivens BJ, Kennedy ET, Packard PT, Sperber BR, Steffen D, Story M

The goal of the Smart Choices Program (SCP) is to provide a simple front-of-the-package icon system to direct consumers to smarter food choices in the supermarket, which will eventually lead to more balanced diets and to more beneficial foods as food manufacturers renovate products to meet the nutrition criteria for carrying the icon. The SCP was developed by a coalition of scientists and nutrition educators, experts with experience with dietary guidelines, public health organizations, and food manufacturers in response to consumer confusion over multiple front-of-the-package systems based on different criteria. Representatives from different government organizations acted as observers. The process of developing the program was facilitated by the nonprofit Keystone Center, an organization that develops consensus solutions to complex health and social policy changes. The nutrition criteria for receiving the SCP icon are specific for product category by indicating “smarter” products within that category. A calorie indicator noting calories per serving and servings per package accompanies the SCP icon to remind consumers that calories do count, even for smarter food choices. For a product to qualify, it first has to be below the threshold for “nutrients to limit” and then (in most cases) it must be above the threshold for one or more nutrients or food groups to encourage. The criteria are based on the 2005 Dietary Guidelines and other consensus science and are transparent and available on the SCP website. This article describes the nutrition criteria and rationales for their selection.

PMID: 20181813 [PubMed - as supplied by publisher]

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Effect of 5 y of calcium plus vitamin D supplementation on change in circulating lipids: results from the Women’s Health Initiative.

Am J Clin Nutr. 2010 Feb 24;

Authors: Rajpathak SN, Xue X, Wassertheil-Smoller S, Van Horn L, Robinson JG, Liu S, Allison M, Martin LW, Ho GY, Rohan TE

BACKGROUND: Dietary calcium and vitamin D intakes may be inversely associated with cardiovascular disease (CVD) risk, possibly because of their potential beneficial effects on circulating lipids. Clinical trials that have evaluated the effect of calcium supplementation on lipids are limited by a short follow-up, and data on vitamin D are scarce. OBJECTIVE: The objective was to evaluate the effect of a longer-term effect (over 5 y) of calcium and vitamin D (CaD) supplementation on changes in the concentrations of several lipids: LDL, HDL, non-HDL, total cholesterol, triglycerides, and lipoprotein(a) [Lp(a)]. DESIGN: The study was conducted in 1259 postmenopausal women in the Calcium plus Vitamin D Trial (1 g elemental Ca as carbonate plus 400 IU vitamin D(3)/d compared with placebo) of the Women’s Health Initiative. Analyses were conducted by intention-to-treat. Repeated measurements on lipids during follow-up were analyzed by linear mixed-effects models. RESULTS: Overall, the change in lipids was relatively small [</=5% except for Lp(a), which was 20-25%], and there was no significant difference in the mean change of any lipid variable between the active and placebo groups. CONCLUSIONS: Our results indicate that CaD supplementation is not associated with lipid changes over 5 y. Existing and future CaD trials should consider evaluating this association for different doses of supplements. This study was registered at clinicaltrials.gov as NCT00000611.

PMID: 20181812 [PubMed - as supplied by publisher]

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The Nutrient Rich Foods Index helps to identify healthy, affordable foods.

Am J Clin Nutr. 2010 Feb 24;

Authors: Drewnowski A

BACKGROUND: The Nutrient Rich Foods (NRF) Index is a formal scoring system that ranks foods on the basis of their nutrient content. When used in conjunction with a food prices database, it can help identify foods that are both nutritious and affordable. OBJECTIVE: Our aim was to identify healthy, affordable foods and food groups by using the NRF index and US Department of Agriculture nutrient composition and food prices data sets. DESIGN: Foods in the US Department of Agriculture Food and Nutrition Database for Dietary Studies 1.0 were scored by using the NRF index. This NRF algorithm was represented by the sum of the percentage of the daily values of 9 nutrients to encourage (protein, fiber, vitamin A, vitamin C, vitamin E, calcium, iron, magnesium, and potassium) minus the sum of the percentage of the maximum recommended values for 3 nutrients to limit (saturated fat, added sugar, and sodium). NRF scores and mean national food prices were calculated per calorie and per US Food and Drug Administration-defined serving. RESULTS: Each of the 9 USDA food groups offered foods of diverse nutritive value and cost. Eggs, dry beans and legumes, and meat and milk products were the lowest-cost sources of protein. Milk and milk products were the lowest-cost sources of calcium, whereas vegetables and fruit were the lowest-cost sources of vitamin C. Milk, potatoes, citrus juices, cereals, and beans had more favorable overall nutrient-to-price ratios than did many vegetables and fruit. Energy-dense grains, sweets, and fats provided most of the calories but fewer nutrients per dollar. CONCLUSION: One important application of nutrient profile models is to help consumers identify foods that provide optimal nutrition at an affordable cost.

PMID: 20181811 [PubMed - as supplied by publisher]

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An antiinflammatory dietary mix modulates inflammation and oxidative and metabolic stress in overweight men: a nutrigenomics approach.

Am J Clin Nutr. 2010 Feb 24;

Authors: Bakker GC, van Erk MJ, Pellis L, Wopereis S, Rubingh CM, Cnubben NH, Kooistra T, van Ommen B, Hendriks HF

BACKGROUND: Low-grade chronic inflammation in overweight subjects is thought to play an important role in disease development. OBJECTIVE: It was hypothesized that specific dietary components are able to reduce low-grade inflammation as well as metabolic and oxidative stress. DESIGN: Dietary products [resveratrol, green tea extract, alpha-tocopherol, vitamin C, n-3 (omega-3) polyunsaturated fatty acids, and tomato extract] selected for their evidence-based antiinflammatory properties were combined and given as supplements to 36 healthy overweight men with mildly elevated plasma C-reactive protein concentrations in a double-blind, placebo-controlled, crossover study with treatment periods of 5 wk. Inflammatory and oxidative stress defense markers were quantified in plasma and urine. Furthermore, 120 plasma proteins, 274 plasma metabolites (lipids, free fatty acids, and polar compounds), and the transcriptomes of peripheral blood mononuclear cells and adipose tissue were quantified. RESULTS: Plasma adiponectin concentrations increased by 7%, whereas C-reactive protein (principal inflammation marker) was unchanged. However, a multitude of subtle changes were detected by an integrated analysis of the “omics” data, which indicated modulated inflammation of adipose tissue, improved endothelial function, affected oxidative stress, and increased liver fatty acid oxidation. CONCLUSIONS: An intervention with selected dietary products affected inflammatory processes, oxidative stress, and metabolism in humans, as shown by large-scale profiling of genes, proteins, and metabolites in plasma, urine, and adipose tissue. This trial was registered at clinical trials.gov as NCT00655798.

PMID: 20181810 [PubMed - as supplied by publisher]

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Performance characteristics of NuVal and the Overall Nutritional Quality Index (ONQI).

Am J Clin Nutr. 2010 Feb 24;

Authors: Katz DL, Njike VY, Rhee LQ, Reingold A, Ayoob KT

BACKGROUND: Improving diets has considerable potential to improve health, but progress in this area has been limited, and advice to increase fruit and vegetable intake has largely gone unheeded. OBJECTIVE: Our objective was to test the performance characteristics of the Overall Nutritional Quality Index (ONQI), a tool designed to help improve dietary patterns one well-informed choice at a time. DESIGN: The ONQI was developed by a multidisciplinary group of nutrition and public health scientists independent of food industry interests and is the basis for the NuVal Nutritional Guidance System. Dietary guidelines, existing nutritional scoring systems, and other pertinent scientific literature were reviewed. An algorithm incorporating >30 entries that represent both micro- and macronutrient properties of foods, as well as weighting coefficients representing epidemiologic associations between nutrients and health outcomes, was developed and subjected to consumer research and testing of performance characteristics. RESULTS: ONQI and expert panel rankings correlated highly (R = 0.92, P < 0.001). In consumer testing, approximately 80% of >800 study participants indicated that the ONQI would influence their purchase intent. ONQI scoring distinguished the more-healthful DASH (Dietary Approaches to Stop Hypertension) diet (mean score: 46) from the typical American diet according to the National Health and Nutrition Examination Survey (NHANES) 2003-2006 (mean score: 26.5; P < 0.01). In linear regression analysis of the NHANES 2003-2006 populations (n = 15,900), the NuVal system was significantly associated with the Healthy Eating Index 2005 (P < 0.0001). Recently generated data from ongoing studies indicate favorable effects on purchase patterns and significant correlation with health outcomes in large cohorts of men and women followed for decades. CONCLUSION: NuVal offers universally applicable nutrition guidance that is independent of food industry interests and is supported by consumer research and scientific evaluation of its performance characteristics.

PMID: 20181809 [PubMed - as supplied by publisher]

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A vegetable-fruit-soy dietary pattern protects against breast cancer among postmenopausal Singapore Chinese women.

Am J Clin Nutr. 2010 Feb 24;

Authors: Butler LM, Wu AH, Wang R, Koh WP, Yuan JM, Yu MC

BACKGROUND: Prospective epidemiologic studies in Asian populations consistently show that soy is protective against breast cancer. OBJECTIVE: The objective was to prospectively evaluate whether the protective effect of soy is due to soy isoflavones alone or to their combination with other beneficial dietary factors in an Asian population. DESIGN: Using principal components analysis, we previously identified a “meat-dim sum” pattern characterized by meat, starch, and dim sum items and a “vegetable-fruit-soy” pattern characterized by cruciferous vegetables, fruit, and tofu items in a population-based cohort of Singapore Chinese initiated between 1993 and 1998. Component scores representing intakes of each pattern were used in multivariable Cox regression models to analyze the relation between diet at baseline and breast cancer incidence. RESULTS: As of 31 December 2005, 629 incident breast cancer cases had been diagnosed among the 34,028 women. With greater intake of the vegetable-fruit-soy dietary pattern, we observed a dose-dependent trend (P < 0.01) for decreasing breast cancer risk among postmenopausal women [hazard ratio (HR): 0.70; 95% CI: 0.51, 0.95 for the fourth compared with first quartile]. A stronger association for the vegetable-fruit-soy pattern was observed among postmenopausal women with >/=5 y of follow-up (HR: 0.57; 95% CI: 0.36, 0.88; P for trend <0.01). No trend was observed for a greater intake of the meat-dim sum dietary pattern and increased breast cancer risk. CONCLUSION: Our findings support the hypothesis that a diet characterized by vegetables, fruit, and soy has an early-acting protective effect on breast carcinogenesis.

PMID: 20181808 [PubMed - as supplied by publisher]

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Review of muscle wasting associated with chronic kidney disease.

Am J Clin Nutr. 2010 Feb 24;

Authors: Workeneh BT, Mitch WE

Muscle wasting increases the morbidity and mortality associated with chronic kidney disease (CKD) and has been attributed to malnutrition. In most patients, this is an incorrect diagnosis because simply feeding more protein aggravates uremia. Instead, there are complex mechanisms that stimulate loss of skeletal muscle, involving activation of mediators that stimulate the ATP-dependent ubiquitin-proteasome system (UPS). Identified mediators of muscle protein breakdown include inflammation, metabolic acidosis, angiotensin II, and neural and hormonal factors that cause defects in insulin/insulin-like growth factor I (IFG-I) intracellular signaling processes. Abnormalities in insulin/IGF-I signaling activate muscle protein degradation in the UPS and caspase-3, a protease that disrupts the complex structure of muscle proteins to provide substrates for the UPS. During the cleavage of muscle proteins, caspase-3 leaves behind a characteristic 14-kD actin fragment in the insoluble fraction of muscle, and characterization of this fragment identifies the presence of muscle catabolism. Thus, it could become a marker of excessive muscle wasting, providing a method for early detection of muscle wasting. Another consequence of activation of caspase-3 in muscle is stimulation of the activity of the proteasome, which increases the degradation of muscle proteins. Treatment strategies for blocking muscle wasting include correction of metabolic acidosis, which can suppress muscle protein losses in patients with CKD who are or are not being treated by dialysis. Correcting acidosis also improves bone metabolism in CKD and hence should be a goal of therapy. Exercise training is a potentially beneficial approach, but more information is needed to optimize exercise regimens. Replacing testosterone deficits can improve muscle mass in men, but dosing and side effects in women have not been adequately tested. Although insulin resistance occurs early in the course of CKD, there are no effective means of correcting it. Consequently, new therapies that can safely suppress muscle wasting are needed.

PMID: 20181807 [PubMed - as supplied by publisher]

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