|SOURCE: Georgetown University |
Georgetown University's Center for Food and Nutrition: Nuts Shown to Have Health Benefits
WASHINGTON, Sept. 20 /PRNewswire/ -- Adding nuts to a healthy, balanced diet may provide a number of health benefits, according to researchers speaking today at Georgetown University's Center for Food and Nutrition Policy. At a conference titled ``Making the Claim for Nuts,'' researchers discussed the role of nuts in heart disease, cancer and weight control.
``Tree nuts have long been perceived as a high-fat, high-calorie food to be avoided,'' said Lester M. Crawford, DVM, PhD, Director and Research Professor at the Center. ``But with a growing body of positive research, particularly in the area of heart disease, tree nuts are finally getting the attention that they deserve.''
While high in total fat, tree nuts are a rich source of unsaturated fats that have important health attributes. According to conference keynote speaker Penny Kris-Etherton, PhD, RD of Pennsylvania State University, ``When included in the diet, the fatty acids, vitamins, minerals and phytonutrients contained in tree nuts may interact synergistically to produce marked health benefits.''
To date, there have been five large epidemiological studies examining the relationship between nut consumption and coronary heart disease (CHD). ``All of these studies found an inverse association between nut intake and CHD risk,'' said Gary Fraser, MD of Loma Linda University, California, principal investigator for one of the five studies. In the most recent, the Nurses' Health Study, researchers found that women who ate at least 5 ounces of nuts per week had a 35 percent lower risk of CHD than women who rarely ate nuts. Similar findings have been seen in men.
A number of clinical studies revealed beneficial effects of nuts on blood lipid levels, supporting the epidemiological findings. ``The beneficial effects of nuts on blood lipids may be due to the fact that nuts are rich in unsaturated fats and contain a variety of protective nutrients, including omega-3 fatty acids, vitamin E, selenium, magnesium and fiber,'' said Joan Sabate, MD, DrPH of Loma Linda University.
Tree nuts may also eventually prove to be effective in protecting against certain forms of cancer. Paul Davis, PhD, University of California, Davis, said, ``While the role of specific nuts in cancer will need to be much more fully explored and defined, the increasing evidence for benefits from nuts suggests that the 'nuts equals a high-fat, high-calorie food' which mean 'to be avoided' needs to be reassessed.''
Finally, researchers have found that including nuts in the diet does not appear to cause weight gain, as long as total calories are controlled. In an 18-month study conducted at Brigham and Women's Hospital in Boston, researchers compared a diet containing 35 percent calories from fat to a low fat diet (20 percent of calories from fat) in 101 overweight men and women. Both diets were limited to 1200 calories for women and 1500 calories for men, with the additional fat in the moderate fat group coming from nuts and olive and canola oils.
``After six months, weight loss was comparable in both groups,'' stated Kathy McManus, MS, RD, of Brigham and Women's Hospital. ``However, at the end of 18 months, there was a significant difference in participation rates.'' While 54 percent of the moderate fat group was still actively participating, only 20 percent remained in the low fat group. ``A moderate fat diet may contribute more flavor and variety, resulting in greater participation rates,'' McManus said.
As the research on tree nuts continues to grow, it appears that eating a handful (one ounce) of mixed nuts a day, as part of a healthy diet, may help curb the appetite and provide other health benefits.
SOURCE: Georgetown University