Plateful of Beta-Carotene: A Good Thing


Sweet potatoes, squash, pumpkin, carrots … beta-carotene is easily identified in the rich oranges of fall vegetables — and is certainly a good force against the evils of free radicals.

But beware of large-dose beta-carotene nutritional supplements, advise two leading scientific groups. Studies have pointed to potential problems, such as increased cancer risk.

The Mechanism

Like other supplements could boost Preventive Services Task Force has looked at the top studies and also found no evidence that beta-carotene [supplements] protects against heart disease and cancer — specifically , prostate, , breast, or nonmelanoma skin cancer in middle-aged and older adults.

In fact, the Task Force warned against taking beta-carotene nutritional supplements to and cancer.

Some of the evidence:

Heart disease and stroke: The Cleveland Clinic researchers compiled data from eight trials with follow-up ranging from one to 12 years. Those who took beta-carotene supplements had a small but significant increase in deaths from all causes, including heart disease and stroke. The findings were published June 2003 in The Lancet.

Lung cancer: A study of nearly 29,000 male smokers in Finland showed that those who took a daily beta-carotene nutritional supplement had an 18% higher rate of lung cancer. That study was published in The Journal of the American Medical Association in July 2003.

A study of more than 120,000 people showed that in a 10-year period those who ate the most fruits and vegetables had a 20%-25% lower risk of lung cancer. That study was published in the American Journal of Clinical Nutrition.

Colon Polyps: In a study of 700 people who had a benign polyp removed, those who took beta-carotene nutritional supplements — and who didn’t smoke or drink — had a marked decrease in colon polyps within the four-year follow-up period.

However, those who smoked or drank alcohol — and took beta-carotene nutritional supplements — had a modest increase in recurrence of colon polyps. If they smoked and drank more than one alcoholic drink per day, beta-carotene doubled their risk of polyp recurrence. That study appeared in the May 2003 Journal of the National Cancer Institute.

Bottom Line

It may be that at a lower dose, beta-carotene nutritional supplements may have benefits — that only higher doses are dangerous, says Mayne.

But a better strategy is to eat beta-carotene-rich foods — such as carrots, oranges, sweet potatoes, squash, yams, apricots, collards, spinach, and mustard greens, she notes.

“Possibly, beta-carotene and other compounds found naturally in food work together to enhance the effectiveness of each other,” she tells WebMD.