New research from Canada suggests that a diet rich in fruits and vegetables may help prevent pancreatic cancer, a particularly deadly type of tumor.

The findings, based on a comparison of 585 pancreatic cancer patients and about 4,779 adults without the disease, suggest that the risk of the cancer declines as fruit and vegetable intake increases.

Among cancers, pancreatic tumors have one of the most dismal survival rates, with less than 5 percent of patients still alive 5 years after diagnosis. The poor prognosis is in large part due to the fact that the disease is rarely caught early.

Because of this, uncovering the modifiable risk factors for the disease is vital, according to Dr. Parviz Ghadirian of the University of Montreal, one of the authors of the new study.

Using data from a large study of Canadians diagnosed with cancer between 1994 and 1997, Ghadirian and his colleagues found that higher intakes of fresh fruit and cruciferous vegetables, such as broccoli and cauliflower, were associated with a lower risk of pancreatic cancer.

For reasons that are unclear, the relationship was confined to men; those with the highest fruit and vegetable intakes were about half as likely to develop pancreatic cancer as those with the lowest intakes. There was no clear association between diet and pancreatic cancer risk among women.

The findings, published in the International Journal of Cancer, add to a growing body of evidence on the role of diet in pancreatic cancer risk. Some research has tied higher consumption of fruits, vegetables and fiber to a lower risk of the disease, while other studies have suggested that diets heavy in saturated fat, salted meats or dairy products may raise the risk.

In the current study all of the subjects filled out questionnaires on their lifestyle habits, which included reporting how often they'd eaten various foods over the previous two years.

In a separate newly published study of the same group, Ghadirian and his colleagues found that the antioxidant lycopene, specifically, appeared protective against pancreatic cancer -- again, only men.

Lycopene, obtained mainly through tomatoes and tomato products, belongs to a family of plant compounds called carotenoids, some of which are converted in the body to the antioxidant vitamin A.

In the current study, adults with high intakes of fruits and vegetables tended to favor fresh fruits like apples, oranges and cantaloupe, and cruciferous vegetables like broccoli and cauliflower. These foods, Ghadirian and his colleagues note, are key sources of carotenoids and vitamin C. another antioxidant that has been tied to lower pancreatic cancer risk.

It's thought that antioxidants may help ward off cancer by mopping up oxygen free radicals -- molecules that, though a natural byproduct of metabolism, can result in potentially disease-causing damage to cells over time.

With its often rapidly fatal course, the only way to address pancreatic cancer right now is through prevention, Ghadirian and his colleagues note in their report.

Not smoking is one way to do that, Ghadirian said, and following a diet rich in fiber, fruits and vegetables may be another.

SOURCE: International Journal of Cancer, May 1, 2005.