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In Brief: What if it were fruit or vegetables?

In Brief

What if it were fruit or vegetables?

When it comes to fruit and vegetables, we usually can have our apples and eat our carrots, too. But what if you had to pick one over the other? Fruit might be the better choice, according to some recent research.

Harvard researchers analyzed Nurses' Health Study data to see whether fruit and vegetable consumption was related to colorectal polyps, common precursors of colorectal cancer.

After some statistical slicing and dicing, they found that a high-fruit diet (five servings a day or more) significantly lowered (by about 40%) the risk of polyps, but a vegetable-stocked one did not. Further analysis pointed to citrus fruit as especially protective. Legumes (beans, lentils, peas, soybeans) were also polyp deterrents.

The explanation? There are several possibilities. Fruit is eaten as dessert or a snack, and fruit juice, which tends to get counted as fruit in epidemiological studies, is often a breakfast drink. Vegetables are often part of dinner, going hand-in-hand with red meat — and high red-meat consumption is a well-documented risk factor for colon cancer. Fruit is usually eaten raw and may supply more fiber than vegetables.

It may not be fruit, as such, but fruit as a bellwether for a healthy lifestyle that accounts for the results. The Harvard researchers say that the participants in the Nurses' Health Study who ate a lot of fruit also exercised more, drank less alcohol, and had healthier body weights.

But hold on; fruit itself may deserve some of the credit here. Fruit, particularly citrus fruit, contains folate, and the researchers cite research linking folate consumption to a lower risk for polyps.

Folate has an impressive resume as a cancer fighter. Molecular biologists have shown that it plays an important role in DNA repair and may head off cancer-causing mutations. And epidemiologists have found connections between folate consumption and cancer protection in many studies. For example, Swedish researchers reported in the March 15, 2006, Journal of the National Cancer Institute that high intake of folate from food (but not, interestingly, from supplements) lowers the risk of developing pancreatic cancer. At about the same time, American Cancer Society epidemiologists reported results suggesting that high folate intake lowers a man's risk of developing advanced prostate cancer.

Last updated:	September 05, 2008