Walnuts decrease risk of cardiovascular disease: a summary of efficacy and biologic mechanisms

Dietary Protocols to Maximize Disease Reversal and Long-Term Safety

This article covers some important concepts and controversies in modern nutritional science. It describes a diet style designed to maximize health, longevity, and disease reversal—foundationally structured on the quality and comprehensive adequacy of nutrients rather than the balance of macronutrients, as is more popular today. I call such a diet, which attempts to optimize micronutrients, a nutritarian diet. I will review a small case series demonstrating typical results in diabetics and some of my clinical observations over the last 25 years treating people with a nutritarian diet, which could be either vegan or flexitarian. I will also discuss health concerns observed from an unsupplemented vegan diet, specifically the risk of depression and later life dementia in individuals with enhanced need for long-chain omega-3 fatty acids.

Novel multimetabolite prediction of walnut consumption by a urinary biomarker model in a free-living population: the PREDIMED study

The beneficial impact of walnuts on human health has been attributed to their unique chemical composition. In order to characterize the dietary walnut fingerprinting, spot urine samples from two sets of 195 (training) and 186 (validation) individuals were analyzed by an HPLC-q-ToF-MS untargeted metabolomics approach, selecting the most discriminating metabolites by multivariate data analysis (VIP ≥ 1.5). Stepwise logistic regression analysis was used to design a multimetabolite prediction biomarker model. The global performance of the model and each included metabolite in it was evaluated by receiver operating characteristic curves, using the area under the curve (AUC) values. Dietary exposure to walnuts was characterized by 18 metabolites, including markers of fatty acid metabolism, ellagitannin-derived microbial compounds, and intermediate metabolites of the tryptophan/serotonin pathway. The predictive model of walnut exposure included at least one compound of each class. The AUC (95% CI) for the combined biomarker model was 93.4% (90.1-96.8%) in the training set and 90.2% (85.9-94.6%) in the validation set. The AUCs for individual metabolites were ≤85%. As far as we know, this is the first study proposing a combination of biomarkers of walnut exposure in a population under free-living conditions, as considered in epidemiological studies examining associations between diet and health outcomes.

What comes first: the food or the nutrient? Executive summary of a symposium

This article summarizes background materials and presentations at a symposium that considered the issue of the role of foods and dietary patterns vs. nutrients in relation to chronic disease risk. A model of food synergy is presented as a basis for studying whole foods and dietary patterns. Findings from a series of studies of walnuts were presented and support the concept that walnuts are a healthy food, with specific benefits in a mouse model of breast cancer growth, reductions in cardiovascular disease risk factors in humans, and motor performance and in vitro, in vivo, and ex vivo cellular response to challenge in an aged-rat model.

Effects of supplementing n-3 fatty acid enriched eggs and walnuts on cardiovascular disease risk markers in healthy free-living lacto-ovo-vegetarians: a randomized, crossover, free-living intervention study

Background

Plant and marine n-3 fatty acids (FA) may favorably modify select markers of cardiovascular disease risk. Whether supplementing the habitual diet of lacto-ovo-vegetarians (LOV) with walnuts (containing α-linolenic acid, ALA) and n-3 FA enriched eggs (containing primarily docosahexaenoic acid, DHA and ALA) would have equivalent effects on CVD risk factors is explored in this study.

Methods

In this study, 20 healthy free-living LOVs following their habitual diet were randomly assigned in a crossover design to receive one of three supplements: n-3 FA enriched egg (6/week), walnuts (28.4 g, 6/week) or a standard egg, 6/week (control) for 8 weeks each with 4-wk washout between treatments. Erythrocyte membrane fatty acids, serum lipids and inflammatory markers were measured at the end of each treatment.

Results

Dietary compliance was observed by an expected increase in erythrocyte membrane ALA following the walnut treatment and in DHA following the n-3 FA enriched egg treatment. Walnut treatment lowered serum triacylglycerol, total cholesterol and Apo B (p < 0.05) compared to the standard egg but not the n-3 FA enriched egg treatment. However, walnut treatment significantly reduced total: HDL cholesterol ratio compared to both egg treatments. There were no differences between treatments for any of the inflammatory markers.

Conclusions

For LOV, a direct source of DHA such as n-3 FA enriched eggs seems necessary to increase membrane levels of DHA. However for producing an overall favorable blood lipid profile, daily consumption of a handful of walnuts rich in ALA may be a preferred option for lacto-ovo vegetarian.