Fruits and veggies no help against cancer
Consuming a diet that is high in fruits and vegetables seems to reduce the risk of heart attack and strokes, but not cancer, according to a report in the Journal of the National Cancer Institute.
Dr. Walter C. Willett, from the Harvard School of Public Health in Boston, and colleagues investigated the protective effects of such diets by analyzing data from 71,910 women who participated in the Nurses’ Health study and from 37,725 men who participated in the Health Professionals’ Follow-up Study.
All of the subjects were free from major disease when the studies began in the mid-1980s and they were followed through 1998. Food frequency questionnaires were administered on a regular basis to assess diet.
During follow-up, 9329 cases of heart attack, stroke, cancer, or death occurred among women and 4957 occurred among men.
Compared with no fruit or vegetable intake, consuming five or more servings per day reduced the risk of heart attack and stroke by 12 percent, the researchers note. In contrast, no effect on cancer risk was seen.
Further analysis revealed that consumption of green leafy vegetables provided the greatest reduction in heart attack and stroke risk. Consuming just one serving per day decreased the risk by 11 percent.
“Our results provide further evidence that high intake of fruits and vegetables is associated with a modest reduction in major chronic disease risk and support the recommendation of consuming five or more servings of fruits and vegetables daily,” the authors state.
SOURCE: Journal of the National Cancer Institute, November 3, 2004.
Revision date: July 6, 2011
Last revised: by Jorge P. Ribeiro, MD