Clinical Edge

Summaries of Must-Read Clinical Literature, Guidelines, and FDA Actions

Walnut Ingestion and Diet Quality

Effects on body composition, cardiac risk studied

A walnut supplemented diet with or without dietary counseling to control calorie intake improved diet quality, endothelial function total, and LDL cholesterol in adults at risk for diabetes. This according to a study of 112 participants who were randomly assigned with or without dietary counseling to a walnut-excluded or walnut-included diet (56 g per day) for 6 months. Researchers determined:

• A walnut-included diet for 6 months significantly improved diet quality.

• Endothelial function, LDL cholesterol improved significantly from baseline in the walnut-included diet.

• Body mass index (BMI), percent body fat, visceral fat, fasting glucose, glycated hemoglobin, and blood pressure did not change significantly.

Citation: Njike VY, Ayettey R, Petraro P, Treu JA, Katz DL. Walnut ingestion in adults at risk for diabetes: effects on body composition, diet quality, and cardiac risk measures. BMJ Open Diabetes Research and Care 2015;3:e000115. doi: 10.1136/bmjdrc-2015-000115.

Commentary: Prior studies show that nuts and other foods high in polyunsaturated fats (PUFAs) appear to be beneficial.1 Walnuts have a particularly high level of PUFAs, including high levels of alpha-linolenic acid, which may have beneficial effects decreasing atherosclerosis.2 The result of this and prior studies suggest that nuts, particularly walnuts, can be included as a part of a well-rounded healthy diet. Since nuts have a high caloric density, if we recommend this to patients, we should also emphasize the importance of moderation in nut intake and ideally having the nuts replace other foods, not being added as additional snacks to a person’s current diet. —Neil Skolnik, MD

1. Jiang R, Manson JE, Stampfer MJ, et al. Nut and peanut butter consumption and risk of type 2 diabetes in women. JAMA 2002;288:2554-2560.

2. Ros E, Núñez I, Pérez-Heras A, et al. A walnut diet improves endothelial function in hypercholesterolemic subjects: a randomized crossover trial. Circulation 2004;109:1609-1614.