In a study published in the journal BMJ Open Diabetes Research & Care, researchers demonstrated that eating walnuts may improve overall diet quality, blood vessel function, and LDL (“bad”) cholesterol levels. The study randomly divided 112 people into four groups for six months: the first group received dietary counseling to help reduce calorie intake and was also instructed to eat 56 grams (about 2 ounces) of walnuts per day; the second group received the same calorie reduction counseling but was instructed to exclude walnuts; the third group received no dietary counseling but was instructed to eat 56 grams of walnuts per day; and the fourth group did not receive any dietary counseling and excluded walnuts. Participants took a three-month break from the study, and then the groups were reversed for another six months: those who had not eaten walnuts before were now instructed to eat walnuts and vice versa. Researchers assessed the participants for diet quality, body mass index (BMI), cholesterol levels, and other markers of heart disease risk. Diet quality was assessed using the Healthy Eating Index 2010, a measure of diet quality based on the USDA’s Dietary Guidelines for Americans. Regardless of whether or not the participants received dietary counseling, the researchers found that:
Participants who ate walnuts experienced a statistically significant improvement in their diet quality compared with those who did not eat walnuts, meaning that the addition of walnuts was associated with other positive changes to their overall diet.
Participants who ate walnuts also had improved blood vessel function and LDL cholesterol levels (both markers for cardiovascular disease) compared with those who did not eat walnuts.
There were no significant differences between the groups’ BMI, percent body fat, abdominal fat, HDL cholesterol, blood pressure, and markers of blood sugar control.
These findings add to a growing body of evidence showing that eating walnuts can lower cardiovascular risk without increasing body fat or weight—benefits that appeal to both healthy people and people with type 2 diabetes. The improvement in diet quality found in this study may help explain why eating walnuts has been associated with these health benefits. As this study included a majority of Caucasian women, future research should focus on more diverse populations to determine whether walnuts can provide dietary benefits to other groups. In the meantime, it’s a safe (and tasty) bet to add some walnuts to your sweet and savory dishes.
Source: BMJ Open Diabetes Research & Care