Healthy older adults that ate about a half cup of walnuts every day for two years gained a modest reduction in low-density lipoprotein (LDL), the “bad cholesterol”, reports a study of 636 people from San Diego’s Loma Linda University. Other risk factors for heart health—small LDL particles and intermediate-density lipoprotein—also decreased, signaling a lower chance of cardiovascular events. “Many people are worried about unwanted weight gain when they include nuts in their diet,” says study co-author Emilio Ros, M.D., Ph.D. “Our study found that the healthy fats in walnuts did not cause participants to gain weight.”