According to emerging evidence in four different studies conducted, eating well might still be one of the more effective ways to prevent cancer and promote good health.

Foods like broccoli and soy are believed to offer some protection against cancer, but how this happens is not well understood.

Now, researchers at the University of California, Los Angeles, have discovered a biological mechanism whereby two compounds in these foods might lower the invasive and metastatic potential of breast and ovarian cancer cells.

They found that diindolylmethane (DIM), a compound resulting from digestion of cruciferous vegetables, and genistein, a major isoflavone in soy, reduce production of two proteins whose chemotactic attraction to each other is necessary for the spread of breast and ovarian cancers.

"We think these compounds might slow or prevent the metastasis of breast and ovarian cancer, which would greatly increase the effectiveness of current treatments," said Erin Hsu, a graduate student in molecular toxicology.

"But we need to test that notion in animals before we can be more definitive,¡± Hsu added.

Another study of food consumption, people who ate the largest amounts of flavonols had a 23 percent reduced risk of developing pancreatic cancer compared to those who ate the least, according to a research team led by Laurence Kolonel, M.D., Ph.D., at the Cancer Research Center of Hawaii.

¡®The effect was largest in smokers, presumably because they are at increased pancreatic cancer risk already," said study¡¯s lead author, Ute N?thlings, Dr.

Experts agree that people who have had three or more potentially precancerous adenomatous polyps removed during a colonoscopy should be "rescoped" in three years to make sure the polyps do not recur.

Researchers at the National Cancer Institute (NCI) have identified other factors that independently raise the risk of recurrence.

"In a situation where there are not enough physicians, or where doctors have long waiting lists for those who are not first-timers to a colon cancer check-up, then this risk stratification may help physicians prioritize which patients should be seen first," said Adeyinka Laiyemo, M.D., a cancer prevention fellow at NCI.

The research team used data from participants in the Polyp Prevention Trial (PPT), which assessed the impact of a low-fat, high-fiber, high fruits and vegetables diet on polyp recurrence.

Dr. Laiyemo and his team found that, indeed, the presence of multiple adenomas was the largest risk factor associated with polyp recurrence, but that age, gender and obesity played important, if lesser, roles in stratifying risk.

A new study among AARP members shows that just one additional serving of fruit and vegetables per day may lower your risk of head and neck cancer, but the data suggest that you may not want to stop at just one, according to researchers from the National Cancer Institute.

"Identifying protective factors for head and neck cancer is particularly important as it has a high mortality rate," said Neal Freedman, Ph.D., cancer prevention fellow at the National Cancer Institute.

"Increasing consumption by just one serving of fruit or vegetables per 1000 calories per day was associated with a six percent reduction in head and neck cancer risk," Freedman said.