How Walnuts Could Affect Weight Loss

Walnuts may help women lose weight, lower cholesterol

/ Author:  / Reviewed by: Beth Bolt, RPh

(RxWiki News) Looking to lose weight? You may want to try going a little nuts.

A new study from the University of California at San Diego (UCSD) found that when women ate diets containing the type of unsaturated fat found in walnuts and olive oil, it helped them lose weight. It also helped them improve their cholesterol levels.

Lead study author Cheryl Rock, PhD, RD, said in a press release, "One of the surprising findings of this study was that, even though walnuts are higher in fat and calories, the walnut-rich diet was associated with the same degree of weight loss as a lower fat diet." Dr. Rock is a professor of public health at UCSD.

She continued, "Considering the results of this study, as well as previous walnut research on heart health and weight, there's something to be said for eating a handful of walnuts a day."

For this study, Dr. Rock and team looked at 245 women ages 22 to 72. All of these women were overweight or obese, and were enrolled in a 1-year weight loss intervention program.

Dr. Rock and team assigned the women to one of three groups. The first group ate a diet low in fat, but high in carbohydrates. The second group ate a diet low in carbohydrates, but high in fat.

The third group also ate a high-fat, low-carb diet but included 1.5 ounces of walnuts per day. That's equal to about 10 whole walnuts per day.

After the first six months, the women in all three groups lost about 8 percent of their initial weight overall.

Although the women in the walnut group didn't lose more weight than the other two groups, their cholesterol levels changed for the better. LDL cholesterol, commonly called “bad” cholesterol, dropped significantly in these women. HDL, or "good" cholesterol, also increased more among women in the walnut group than the other two groups.

Unlike most nuts, walnuts primarily contain polyunsaturated fat. They also contain a significant amount of alpha-linolenic acid (ALA), an omega-3 fatty acid.

Because all participants in this study were women, researchers said a walnut-rich diet may not have the same effects in men.

This study was published Feb. 9 in the Journal of the American Heart Association.

The National Institutes of Health and the California Walnut Commission funded this research, making for a potential conflict of interest. No other conflicts of interest were disclosed.

Reviewed by: 
Review Date: 
February 9, 2016
Last Updated:
February 10, 2016