Walnuts, like those featured in this parsley and
walnut salad, provide fiber as well as minerals and other nutrients. Image
courtesy of the Walnut Marketing Board.
Walnuts' Potential New Link to Heart Health
Reported By Marcia Wood July
Walnuts, already shown in some studies to reduce "bad" (LDL)
cholesterol, may have yet another way of enhancing cardiovascular health.
University of California-Davis (UC-Davis) scientists and their Agricultural
Research Service (ARS) and
University of Padova (Italy)
co-investigators have found that laboratory hamsters that ate feed containing
walnuts had significantly lower levels of a natural chemical called endothelin.
The compound causes inflammation of arteries and growth of sticky
depositscalled plaqueon blood vessels. These conditions contribute
to heart disease, the leading cause of death in the United States.
In this six-and-one-half-month study of about 100 hamsters, walnuts
apparently suppressed heart artery endothelin. Walnuts had that effect at all
levels tested, which were the equivalent of a human eating from three to eight
handfuls of walnuts a day.
For the study, scientists used English walnuts, the kind sold in
supermarkets nationwide, adding them to the hamsters' meals as a finely ground
H. Yokoyama, with the ARS
Regional Research Center in Albany, Calif., collaborated in the study,
which was led by research nutritionist Paul A. Davis at UC-Davis.
The study, reported earlier this year in the Journal of Nutrition, builds upon
observations by researchers elsewhere that eating walnuts may affect blood
vessels directly. The California study is the first to demonstrate this by
showing walnuts' ability to suppress artery endothelin in lab animals.
Additional studies are needed to determine if this beneficial effect occurs in
people who eat a moderate amount of walnuts.
Walnuts are a good source of fiber, healthful fatty acids and
minerals. They can be sprinkled on breakfast cereal, tossed with crisp greens
for a lunch or dinner salad, or simply eaten out of hand as a snack.
ARS is the U.S. Department of
Agriculture's chief scientific research agency.