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Walnuts are loaded with folate, vitamin E, and lots of good fats. Although they are also high in calories, they don't seem to contribute to weight gain. Researchers at Yale University Prevention Research Center wanted to determine if eating walnuts daily could help people at risk for diabetes control their cholesterol and blood sugar.
The researchers randomly assigned 112 people ages 25 to 75—70% of whom were women—to two groups. People in both groups were given 2 ounces of walnuts to eat daily. They were told to eat whatever else they wanted but to keep a record of what they ate. One group was also told to eat 366 fewer calories from other food to compensate for the calories added by the walnuts. Both groups ate the walnuts for six months, and their customary diet without walnuts for another six months.
Everyone visited clinical centers every three months to be weighed and measured and to have their blood pressure, cholesterol, and blood sugar levels checked. At those visits, the researchers also evaluated the quality of their diets using the Healthy Eating Index 2010.
The researchers found that participants' total and LDL (bad) cholesterol levels fell significantly when they ate walnuts every day. Moreover, their weight remained stable whether or not they reduced other calories. In addition, their overall diets were healthier when they were eating walnuts. However, adding walnuts had no effect on blood sugar levels or blood pressure. The study was published online Nov. 23, 2015, by BMJ Open Diabetes Research and Care. Nuts are a healthy and potentially guilt-free snack. If you're trying to lower your cholesterol, a handful of walnuts a day is worth a try.
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