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Background Adherence to the Dietary Approaches to Stop Hypertension (DASH) diet enhances potassium intake and reduces sodium intake and blood pressure (BP), but the underlying metabolic pathways are unclear. Objectives Among free-living populations, we delineated metabolic signatures associated with the DASH diet adherence, 24-hour urinary sodium and potassium excretions, and the potential metabolic pathways involved. Methods We used 24-hour urinary metabolic profiling by proton nuclear magnetic resonance spectroscopy to characterize the metabolic signatures associated with the DASH dietary pattern score (DASH score) and 24-hour excretion of sodium and potassium among participants in the United States (n =  2164) and United Kingdom (n =  496) enrolled in the International Study of Macro- and Micronutrients and Blood Pressure (INTERMAP). Multiple linear regression and cross-tabulation analyses were used to investigate the DASH-BP relation and its modulation by sodium and potassium. Potential pathways associated with DASH adherence, sodium and potassium excretion, and BP were identified using mediation analyses and metabolic reaction networks. Results Adherence to the DASH diet was associated with urinary potassium excretion (correlation coefficient, r = 0.42; P  < 0.0001). In multivariable regression analyses, a 5-point higher DASH score (range, 7 to 35) was associated with a lower systolic BP by 1.35 mmHg (95% CI, −1.95 to −0.80 mmHg; P  = 1.2 × 10−5); control of the model for potassium but not sodium attenuated the DASH-BP relation. Two common metabolites (hippurate and citrate) mediated the potassium-BP and DASH-BP relationships, while 5 metabolites (succinate, alanine, S -methyl cysteine sulfoxide, 4-hydroxyhippurate, and phenylacetylglutamine) were found to be specific to the DASH-BP relation. Conclusions Greater adherence to the DASH diet is associated with lower BP and higher potassium intake across levels of sodium intake. The DASH diet recommends greater intake of fruits, vegetables, and other potassium-rich foods that may replace sodium-rich processed foods and thereby influence BP through overlapping metabolic pathways. Possible DASH-specific pathways are speculated but confirmation requires further study. INTERMAP is registered as NCT00005271 at www.clinicaltrials.gov. [ABSTRACT FROM AUTHOR]

Background Dietary recommendations to prevent gout emphasize a low-purine diet. Recent evidence suggests that the Dietary Approaches to Stop Hypertension (DASH) diet reduces serum urate while also improving blood pressure and lipids. Objective To compare the effects of DASH-style diets emphasizing different macronutrient proportions on serum urate reduction. Methods We conducted a secondary analysis of the Optimal Macronutrient Intake Trial to Prevent Heart Disease feeding study, a 3-period, crossover design, randomized trial of adults with prehypertension or hypertension. Participants were provided with 3 DASH-style diets in random order, each for 6 wk. Each DASH-style diet emphasized different macronutrient proportions: a carbohydrate-rich (CARB) diet, a protein-rich (PROT) diet, and an unsaturated fat-rich (UNSAT) diet. In the PROT diet, approximately half of the protein came from plant sources. We compared the effects of these diets on serum urate at weeks 4 and 6 of each feeding period. Results Of the 163 individuals included in the final analysis, the mean serum urate at baseline was 5.1 mg/dL. Only the PROT diet reduced serum urate from baseline at the end of the 6-wk feeding period (–0.16 mg/dL; 95% CI: –0.28, –0.04; P  = 0.007). Neither the CARB diet (–0.03 mg/dL; 95% CI: –0.14, 0.09; P  = 0.66) nor the UNSAT diet (–0.01 mg/dL; 95% CI: –0.12, 0.09; P  = 0.78) reduced serum urate from baseline. The PROT diet lowered serum urate by 0.12 mg/dL (95% CI: –0.20, –0.03; P  = 0.006) compared with CARB and by 0.12 mg/dL (95% CI: –0.20, –0.05; P  = 0.002) compared with UNSAT. Conclusions A DASH-style diet emphasizing plant-based protein lowered serum urate compared with those emphasizing carbohydrates or unsaturated fat. Future trials should test the ability of a DASH-style diet emphasizing plant-based protein to lower serum urate and prevent gout flares in patients with gout. This trial was registered at clinicaltrials.gov as NCT00051350. [ABSTRACT FROM AUTHOR]

Background Short chain fatty acids (SCFAs; e.g., acetate, propionate, and butyrate) are produced by microbial fermentation of fiber in the colon. Evidence is lacking on how high-fiber diets that differ in macronutrient composition affect circulating SCFAs. Objectives We aimed to compare the effects of 3 high-fiber isocaloric diets differing in %kcal of carbohydrate, protein, or unsaturated fat on circulating SCFAs. Based on previous literature, we hypothesized that serum acetate, the main SCFA in circulation, increases on all high-fiber diets, but differently by macronutrient composition of the diet. Methods OmniHeart is a randomized crossover trial of 164 men and women (≥30 y old); 163 participants with SCFA data were included in this analysis. We provided participants 3 isocaloric high-fiber (∼30 g/2100 kcal) diets, each for 6 wk, in random order: a carbohydrate-rich (Carb) diet, a protein-rich (Prot) diet (protein predominantly from plant sources), and an unsaturated fat–rich (Unsat) diet. We used LC-MS to quantify SCFA concentrations in fasting serum, collected at baseline and the end of each diet period. We fitted linear regression models with generalized estimating equations to examine change in ln-transformed SCFAs from baseline to the end of each diet; differences between diets; and associations of changes in SCFAs with cardiometabolic parameters. Results From baseline, serum acetate concentrations were increased by the Prot (β: 0.24; 95% CI: 0.12, 0.35), Unsat (β: 0.21; 95% CI: 0.10, 0.33), and Carb (β: 0.12; 95% CI: 0.01, 0.24) diets; between diets, only Prot compared with Carb was significant (P  = 0.02). Propionate was decreased by the Carb (β: −0.10; 95% CI: −0.16, −0.03) and Unsat (β: −0.10; 95% CI: −0.16, −0.04) diets, not the Prot diet; between diet comparisons of Carb vs. Prot (P  = 0.006) and Unsat vs. Prot (P  = 0.002) were significant. The Prot diet increased butyrate (β: 0.05; 95% CI: 0.00, 0.09) compared with baseline, but not compared with the other diets. Increases in acetate were associated with decreases in insulin and glucose; increases in propionate with increases in leptin, LDL cholesterol, and blood pressure; and increases in butyrate with increases in insulin and glucose, and decreases in HDL cholesterol and ghrelin (P s < 0.05). Conclusions Macronutrient composition of high-fiber diets affects circulating SCFAs, which are associated with measures of appetite and cardiometabolic health. This trial was registered at clinicaltrials.gov as NCT00051350. [ABSTRACT FROM AUTHOR]

Background Adherence to healthy dietary patterns, measured by the Healthy Eating Index (HEI), Alternative Healthy Eating Index (AHEI), and alternate Mediterranean diet (aMed) scores, is associated with a reduced risk of cardiovascular disease. The association between these scores and chronic kidney disease (CKD) is undetermined. Objective We aimed to estimate the association between the HEI, AHEI, and aMed scores and risk of incident CKD. Methods We conducted a prospective analysis in 12,155 participants aged 45–64 y from the Atherosclerosis Risk in Communities (ARIC) Study. We calculated HEI-2015, AHEI-2010, and aMed scores for each participant and categorized them into quintiles of each dietary score. Incident CKD was defined as an estimated glomerular filtration rate <60 mL/min/1.73 m2 accompanied by ≥25% decline in estimated glomerular filtration rate, a kidney disease–related hospitalization or death, or end-stage renal disease. We used cause-specific hazard models to estimate risk of CKD from the quintile of the dietary score through to 31 December 2017. Results There were 3980 cases of incident CKD over a median follow-up of 24 y. Participants who had higher adherence to the HEI-2015, AHEI-2010, and aMed scores were more likely to be female, have higher educational attainment, higher income level, be nonsmokers, more physically active, and diabetic compared with participants who scored lower. All 3 dietary scores were associated with lower CKD risk (P -trend < 0.001). Participants who were in the highest quintile of HEI-2015 score had a 17% lower risk of CKD (HR: 0.83; 95% CI: 0.74, 0.92) compared with participants in the lowest quintile. Those in quintile 5 of AHEI-2010 and aMed scores, respectively, had a 20% and 13% lower risk of CKD compared with those in quintile 1. Conclusion Higher adherence to healthy dietary patterns during middle age was associated with lower risk of CKD. [ABSTRACT FROM AUTHOR]

Background Elevated blood pressure (BP) is a major cause of preventable disease in the United States and around the world. It has been postulated that phosphorus intake may affect BP, with some studies suggesting a direct and others an inverse association. Objectives We systematically reviewed the literature on the association of dietary phosphorus with BP in adults and performed a qualitative synthesis. Methods We included randomized and nonrandomized behavioral intervention and feeding studies (intervention studies) and prospective observational studies that measured dietary phosphorus intake or urinary phosphorus excretion and BP. We excluded studies of supplements, children, or individuals with major medical conditions. We searched PubMed, Embase, Cochrane Trials, and clinicaltrials.gov on 1 June, 2017 and 22 August, 2018. We assessed studies' risk of bias in their assessment of phosphorus exposure and BP. Results We reviewed 4759 publications and included 14 intervention studies (2497 participants), 3 prospective observational cohorts (17,795 participants), and 2 ongoing trials. No included intervention studies were designed specifically to achieve a phosphorus contrast. Two studies found a significant positive association of dietary phosphorus with systolic BP, 4 a significant inverse association, and 8 no significant association. Four studies found a significant inverse association with diastolic BP and 10 no significant associations. Two cohorts found lower risk of incident hypertension comparing the highest with the lowest quintiles of phosphorus intake and 1 found no significant difference: HR: 0.86 (95% CI: 0.75, 0.98); HR: 0.83 (95% CI: 0.68, 1.02); and HR: 0.75 (95% CI: 0.45, 1.27), respectively. Conclusions We found no consistent association between total dietary phosphorus intake and BP in adults in the published literature nor any randomized trials designed to examine this association. This trial was registered at www.crd.york.ac.uk/prospero/ as CRD42017062489. [ABSTRACT FROM AUTHOR]

Background Accurate assessment of dietary intake is essential, but self-report of dietary intake is prone to measurement error and bias. Discovering metabolic consequences of diets with lower compared with higher protein intake could elucidate new, objective biomarkers of protein intake. Objectives The goal of this study was to identify serum metabolites associated with dietary protein intake. Methods Metabolites were measured with the use of untargeted, reverse-phase ultra-performance liquid chromatography–tandem mass spectrometry quantification in serum specimens collected at the 12-mo follow-up visit in the Modification of Diet in Renal Disease (MDRD) Study from 482 participants in study A (glomerular filtration rate: 25–55 mL · min−1 · 1.73 m−2) and 192 participants in study B (glomerular filtration rate: 13–24 mL · min−1 · 1.73 m−2). We used multivariable linear regression to test for differences in log-transformed metabolites (outcome) according to randomly assigned dietary protein intervention groups (exposure). Statistical significance was assessed at the Bonferroni-corrected threshold: 0.05/1193 = 4.2 × 10−5. Results In study A, 130 metabolites (83 known from 28 distinct pathways, including 7 amino acid pathways; 47 unknown) were significantly different between participants randomly assigned to the low-protein diet compared with the moderate-protein diet. In study B, 32 metabolites (22 known from 8 distinct pathways, including 4 amino acid pathways; 10 unknown) were significantly different between participants randomly assigned to the very-low-protein diet compared with the low-protein diet. A total of 11 known metabolites were significantly associated with protein intake in the same direction in both studies A and B: 3-methylhistidine, N-acetyl-3-methylhistidine, xanthurenate, isovalerylcarnitine, creatine, kynurenate, 1-(1-enyl-palmitoyl)-2-arachidonoyl-GPE (P-16:0/20:4), 1-(1-enyl-stearoyl)-2-arachidonoyl-GPE (P-18:0/20:4), 1-(1-enyl-palmitoyl)-2-arachidonoyl-GPC (P-16:0/20:4), sulfate, and γ-glutamylalanine. Conclusions Among patients with chronic kidney disease, an untargeted serum metabolomics platform identified multiple pathways and metabolites associated with dietary protein intake. Further research is necessary to characterize unknown compounds and to examine these metabolites in association with dietary protein intake among individuals without kidney disease. This trial was registered at clinicaltrials.gov as NCT03202914. [ABSTRACT FROM AUTHOR]

Background: The Dietary Approaches to Stop Hypertension (DASH) dietary pattern is recommended for cardiovascular disease risk reduction. Assessment of dietary intake has been limited to subjective measures and a few biomarkers from 24-h urine collections. Objective: The aim of the study was to use metabolomics to identify serum compounds that are associated with adherence to the DASH dietary pattern. Design: We conducted untargeted metabolomic profiling in serum specimens collected at the end of 8 wk following the DASH diet (n = 110), the fruit and vegetables diet (n = 111), or a control diet (n = 108) in a multicenter, randomized clinical feeding study (n = 329). Multivariable linear regression was used to determine the associations between the randomized diets and individual log-transformed metabolites after adjustment for age, sex, race, education, body mass index, and hypertension. Partial least-squares discriminant analysis (PLS-DA) was used to identify a panel of compounds that discriminated between the dietary patterns. The area under the curve (C statistic) was calculated as the cumulative ability to distinguish between dietary patterns. We accounted for multiple comparisons with the use of the Bonferroni method (0.05 of 818 metabolites = 6.11 × 10-5). Results: Serum concentrations of 44 known metabolites differed significantly between participants randomly assigned to the DASH diet compared with both the control diet and the fruit and vegetables diet, which included an amino acid, 2 cofactors and vitamins (n = 2), and lipids (n = 41). With the use of PLS-DA, component 1 explained 29.4% of the variance and component 2 explained 12.6% of the variance. The 10 most influential metabolites for discriminating between the DASH and control dietary patterns were N-methylproline, stachydrine, tryptophan betaine, theobromine, 7-methylurate, chiro-inositol, 3-methylxanthine, methyl glucopyranoside, β-cryptoxanthin, and 7-methylxanthine (C statistic = 0.986). Conclusions: An untargeted metabolomic platform identified a broad array of serum metabolites that differed between the DASH diet and 2 other dietary patterns. This newly identified metabolite panel may be used to assess adherence to the DASH dietary pattern. [ABSTRACT FROM AUTHOR]

Background: Interindividual variation in the response to diet is common, but the underlying mechanism for such variation is unclear. Objective: The objective of this study was to use a metabolic profiling approach to identify a panel of urinary metabolites representing individuals demonstrating typical (homogeneous) metabolic responses to healthy diets, and subsequently to define the association of these metabolites with improvement of risk factors for cardiovascular diseases (CVDs). Design: 24-h urine samples from 158 participants with prehypertension and stage 1 hypertension, collected at baseline and following the consumption of a carbohydrate-rich, a protein-rich, and a monounsaturated fat-rich healthy diet (6 wk/diet) in a randomized, crossover study, were analyzed by proton ('H) nuclear magnetic resonance (NMR) spectroscopy. Urinary metabolite profiles were interrogated to identify typical and variable responses to each diet. We quantified the differences in absolute excretion of metabolites, distinguishing between dietary comparisons within the typical response groups, and established their associations with CVD risk factors using linear regression. Results: Globally all 3 diets induced a similar pattern of change in the urinary metabolic profiles for the majority of participants (60.1%). Diet-dependent metabolic variation was not significantly associated with total cholesterol or low-density lipoprotein (LDL) cholesterol concentration. However, blood pressure (BP) was found to be significantly associated with 6 urinary metabolites reflecting dietary intake [proline-betaine (inverse), carnitine (direct)], gut microbial co-metabolites [hippurate (direct), 4-cresyl sulfate (inverse), phenylacetylglutamine (inverse)], and tryptophan metabolism [N-methyl- 2-pyridone-5-carboxamide (inverse)]. A dampened clinical response was observed in some individuals with variable metabolic responses, which could be attributed to nonadherence to diet (<25.3%), variation in gut microbiome activity (7.6%), or a combination of both (7.0%). Conclusions: These data indicate interindividual variations in BP in response to dietary change and highlight the potential influence of the gut microbiome in mediating this relation. This approach provides a framework for stratification of individuals undergoing dietary management. The original OmniHeart intervention study and the metabolomics study were registered at www.clinicaltrials.gov as NCT00051350 and NCT03369535, respectively. [ABSTRACT FROM AUTHOR]

Background: For decades, dietary sodium intake in the United States has remained high, and few studies have examined strategies for maintaining recommended intakes. Objective: We examined the effects of a behavioral intervention, which emphasized spices and herbs, on the maintenance of sodium intake at the recommended intake of 1500 mg/d in individuals to whom the US Dietary Guidelines for Americans apply. Design: We conducted a 2-phase study that included adults ≥ 8 y of age for whom Dietary Guidelines for Americans recommends 1500 mg Na/d. The study was conducted in Baltimore, Maryland, from 2012 to 2014. In phase 1, 55 individuals consumed a low-sodium diet for 4 wk. Participants were provided all foods, snacks, and calorie-containing drinks. In phase 2, 40 participants from phase 1 were randomly assigned to either a behavioral intervention to reduce sodium intake (n = 20) or a self-directed control group (n = 20) for 20 wk. The primary study outcome was the change in mean 24-h urinary sodium excretion during phase 2. Linear regression analyses were used to determine intervention effects on urinary sodium excretion. Results: Participant characteristics were as follows: women: 65%; African American: 88%; hypertension: 63%; diabetes: 18%; mean age: 61 y; and mean body mass index (in kg/m2): 30. At the end of phase 2, mean 24-h sodium excretion was lower in the behavioral intervention than in the self-directed group (mean difference: 2956.8 mg/d; 95% CI: 21538.7, 2374.9 mg/d) after sodium intake at screening was controlled for (P = 0.002). These findings persisted in sensitivity analyses that excluded potentially incomplete urine collections [Mage’s equation mean difference: 21090 mg/d (P = 0.001); Joosens' equation mean difference: 2796 mg/d (P = 0.04)]. Conclusions: A multifactorial behavioral intervention emphasizing spices and herbs significantly reduced sodium intake. Because of the ubiquity of sodium in the US food supply, multilevel strategies addressing individual behaviors and the food supply are needed to improve adherence to recommendations. This trial was registered at clinicaltrials.gov as NCT01615159. [ABSTRACT FROM AUTHOR]

The authors reflect on the benefits and risks of potassium-enriched salt substitutes. Other topics include the Salt Substitute in India Study (SSiIS) to assess the effects of salt substitute on blood pressure (BP) among patients with hypertension, and the recommended dietary sodium intake by the World Health Organization (WHO) to prevent adverse consequences like kidney disease and cardiovascular disease.

Background: Elevated serum phosphorus is associated with all-cause mortality, but little is known about risk associated with dietary phosphorus intake. Objective: We investigated the association between phosphorus intake and mortality in a prospective cohort of healthy US adults (NHANES III; 1998-1994). Design: Study participants were 9686 nonpregnant adults aged 20-80 y without diabetes, cancer, or kidney or cardiovascular disease. Exposure to dietary phosphorus, which was assessed by using a 24-h dietary recall, was expressed as the absolute intake and phosphorus density (phosphorus intake divided by energy intake). All-cause and cardiovascular mortality was assessed through 31 December 2006. Results: Median phosphorus intake was 1166 mg/d (IQR: 823-1610 mg/d); median phosphorus density was 0.58 mg/kcal (0.48-0.70 mg/kcal). Individuals who consumed more phosphorus-dense diets were older, were less often African American, and led healthier lifestyles (smoking, physical activity, and Healthy Eating Index). In analyses adjusted for demographics, cardiovascular risk factors, kidney function, and energy intake, higher phosphorus intake was associated with higher all-cause mortality in individuals who consumed >1400 mg/d [adjusted HR (95% CI): 2.23 (1.09, 4.5) per 1-unit increase in ln(phosphorus intake); P = 0.03]. At,1400 mg/d, there was no association. A similar association was seen between higher phosphorus density and all-cause mortality at a phosphorus density amount .0.35 mg/kcal [adjusted HR (95% CI): 2.27 (1.19, 4.33) per 0.1-mg/kcal increase in phosphorus density; P =0 . 0 1 ]. A t <0.35 mg/kcal (approximately the fifth percentile), lower phosphorus density was associated with increased mortality risk. Phosphorus density was associated with cardiovascular mortality [adjusted HR (95% CI): 3.39 (1.43, 8.02) per 0.1 mg/kcal at .0.35 mg/kcal; P = 0.01], whereas no association was shown in analyses with phosphorus intake. Results were similar by subgroups of diet quality and in analyses adjusted for sodium and saturated fat intakes. Conclusions: High phosphorus intake is associated with increased mortality in a healthy US population. Because of current patterns in phosphorus consumption in US adults, these findings may have important public health implications. [ABSTRACT FROM AUTHOR]

Background: The 2010 Dietary Guidelines Advisory Committee report contained dietary patterns developed by using nutrient-dense foods. In most cases, low-sodium forms of foods were incorporated into the patterns. Objectives: We wanted to determine whether choosing lower-sodium foods could lower the sodium content to 1500 mg without compromising nutrient adequacy. We also explored the effect of choosing typical foods (more calories with higher sodium) and the feasibility of implementing sodium recommendations on a density basis (mg Na/kcal). Design: Food patterns developed during the 2010 Dietary Guidelines development process were used as the base for this analysis. Modeling was then used to analyze the effect of substituting lower-sodium foods on nutrient adequacy. Results: Sodium amounts in the base model varied directly with energy level (1.0 mg Na/kcal) and ranged from 996 to 3176 mg/d. Amounts in the lowest-sodium model also varied with energy level (~0.5 mg/kcal) and ranged from 500 to 1250 mg/d. A comparison of sodium density for the base and the lowest sodium models showed that sodium in the lowest model is ~50% of the base. For typical food choices, sodium amounts were much higher (1.6-2.0 mg/kcal and 1715-5078 mg/d). Comparison of sodium density for the base and the typical food choice models showed that amounts were 1.6-2.0 times greater than the base. Conclusions: By choosing only low-sodium foods, it was possible to construct nutritionally adequate dietary patterns with 1500 mg Na/d. Sodium density (mg Na/kcal) is a practical approach for expressing sodium recommendations. [ABSTRACT FROM AUTHOR]

Background: In observational studies, increased vitamin C intake, vitamin C supplementation, and higher blood concentrations of vitamin C are associated with lower blood pressure (BP). However, evidence for blood pressure-lowering effects of vitamin C in clinical trials is inconsistent. Objective: The objective was to conduct a systematic review and meta-analysis of clinical trials that examined the effects of vitamin C supplementation on BP. Design: We searched Medline, EMBASE, and Central databases from 1966 to 2011. Prespecified inclusion criteria were as follows: 1) use of a randomized controlled trial design; 2) trial reported effects on systolic BP (SBP) or diastolic BP (DBP) or both; 3) trial used oral vitamin C and concurrent control groups; and 4) trial had a minimum duration of 2 wk. BP effects were pooled by random-effects models, with trials weighted by inverse variance. Results: Twenty-nine trials met eligibility criteria for the primary analysis. The median dose was 500 mg/d, the median duration was 8 wk, and trial sizes ranged from 10 to 120 participants. The pooled changes in SBP and DBP were -3.84 mm Hg (95% CI: -5.29, -2.38 mm Hg; P < 0.01) and -1.48 mm Hg (95% CI: -2.86, -0.10 mm Hg; P = 0.04), respectively. In trials in hypertensive participants, corresponding reductions in SBP and DBP were -4.85 mm Hg (P < 0.01) and -1.67 mm Hg (P = 0.17). After the inclusion of 9 trials with imputed BP effects, BP effects were attenuated but remained significant. Conclusions: In short-term trials, vitamin C supplementation reduced SBP and DBP. Long-term trials on the effects of vitamin C supplementation on BP and clinical events are needed. [ABSTRACT FROM AUTHOR]

Background: Despite the reported benefits, weight loss is not always advised for older adults because some observational studies have associated weight loss with increased mortality. However, the distinction between intentional and unintentional weight loss is difficult to make in an observational context, so the effect of intentional weight loss on mortality may be clarified in the setting of a randomized controlled trial. Objective: The objective was to determine the effect of intentional weight loss on all-cause mortality by using follow-up data from a randomized trial completed in 1995 that included a weight-loss arm. Design: The Trial of Nonpharmacologic Intervention in the Elderly (TONE) used a 2 × 2 factorial design to determine the effect of dietary weight loss, sodium restriction, or both on blood pressure control in 585 overweight or obese older adults being treated for hypertension (mean ° SD age: 66 ° 4 y; 53% female). All-cause mortality was ascertained by using the Social Security Index and National Death Index through 2006. Results: The mortality rate of those who were randomly assigned to the weight-loss intervention (n = 291; mean weight loss: 4.4 kg) did not differ significantly from that of those who were not randomly assigned to this group (n = 294; mean weight loss: 0.8 kg). The adjusted HR was 0.82 (95% CI: 0.55, 1.22). Conclusions: Intentional dietary weight loss was not significantly associated with increased all-cause mortality over 12 y of follow-up in older overweight or obese adults. Additional studies are needed to confirm and extend our findings to older age groups. [ABSTRACT FROM AUTHOR]

Background: Lipid peroxidation may be important in the pathogenesis of atherosclerosis, particularly in its earliest stages. Evidence predominantly from in vitro studies suggests that antioxidant vitamins can prevent lipid peroxidation and that vitamin C and vitamin E have synergistic effects. However, in vivo evidence in support of these hypotheses is sparse. Objective: The objective was to determine the effects of vitamin C and vitamin E, alone or in combination, on in vivo lipid peroxidation. Design: We conducted a placebo-controlled, 2 × 2 factorial trial of vitamin C (500 mg ascorbate/d) and vitamin E (400 IU RRR-α-tocopheryl acetate/d) supplementation in 184 nonsmokers. The mean duration of supplementation was 2 mo. The outcome measures were changes from baseline in urinary 8-isoprostaglandin F2α, urinary malondialdehyde + 4-hydroxyalkenals, and serum oxygen-radical absorbance capacity. Results: The within-group mean changes (and 95% CIs) in urinary 8-iso-prostaglandin F2α (pg/mg creatinine) were 9.0 (-125.1, 143.1), -150.0 (-275.4, -24.6), -141.3 (-230.5, -52.1), and -112.5 (-234.8, 9.8) in the placebo, vitamin C alone, vitamin E alone, and vitamins C + E groups, respectively. No synergistic effect of these 2 vitamins on urinary 8-iso-prostaglandin F2α was observed (P = 0.12). Neither vitamin had an effect on urinary malondialdehyde + 4-hydroxyalkenals. Vitamin C, but not vitamin E, increased serum oxygen-radical absorbance capacity (P = 0.01). Conclusions: Supplementation with vitamin C or vitamin E alone reduced lipid peroxidation to a similar extent. Supplementation with a combination of vitamins C and E conferred no benefit beyond that of either vitamin alone. [ABSTRACT FROM AUTHOR]

The authors discuss a feeding study that evaluates the 2010 Dietary Guidelines for Americans dietary pattern. The authors think that the power calculations in the study were overly optimistic. They said that the study's eligibility criteria may have affected study power. Several caveats to consider when interpreting the systolic blood pressure findings were mentioned.

A letter to the editor in response to an article on dietary phosphorus intake by A. R. Change and colleagues in the 2014 issue of the "American Journal of Clinical Nutrition" is presented.