Cancer prevention is important, but it is particularly crucial for those types of cancer not easily detected early. Ovarian cancer, for example, often has no symptoms in early stages and is frequently diagnosed at a more advanced stage, resulting in poorer survival rates than other cancers.
But could natural compounds in plant-based foods help to prevent ovarian cancer?
A new study suggests that diets high in certain flavonoid compounds found in vegetables, fruits, beans and tea may significantly lower a woman’s risk of developing ovarian cancer.
Flavonoids are a large family of antioxidant compounds known as phytochemicals. They are part of a plant’s natural defense system that helps the plant fight off disease and infection.
Lowered disease risk
Research suggests these compounds could help prevent a variety of diseases in humans — including cancer — by protecting cells from DNA damage. Scientists believe some flavonoids may also deter cancer development by helping to regulate cell growth and fight inflammation or by changing hormone levels.
A new study, published in the International Journal of Cancer in 2007, involved almost 67,000 women in the Nurses’ Health Study and looked at flavonoid consumption over 14 years. Although total flavonoid consumption was not shown as related to the risk of developing ovarian cancer, two particular flavonoids were.
Kaempferol — a flavonoid found in tea, broccoli, kale and spinach — and luteolin — which is provided by peppers, carrots, cabbage and celery — were both identified as cancer protective. Women who consumed the most of these two flavonoids were 40 percent and 34 percent less likely, respectively, to develop ovarian cancer compared to women who consumed the least. Participants who consumed high levels of a third phytochemical, myricetin (found in tea, dried beans, raisins and blueberries), also seemed somewhat protected.
Flavonoid compounds found in vegetables may be part of what’s behind an apparent link between vegetable consumption and lower risk of ovarian cancer. A landmark report on diet and cancer risk published by the American Institute for Cancer Research in 2007 noted that some evidence suggests that non-starchy vegetables may offer protection against ovarian cancer. The report emphasizes that protection could come from any of several families of phytochemicals, as well as dietary fiber, vitamins and minerals.
Keep eating those veggies
Researchers note that determining the relative importance of one individual constituent in a food is difficult. A protective effect is likely the result of a combination of influences on several pathways involved in cancer development.
Evidence that supports phytochemicals’ role in fighting ovarian cancer is growing. A 2007 study published in the British Journal of Nutrition linked greater consumption of carotenoid phytochemicals with a 67 percent lower risk of ovarian cancer. This included not only beta-carotene, the oft-cited carotenoid in deep-orange vegetables and fruits, but also alpha-carotene, beta-cryptoxanthin, lutein and zeaxanthin — carotenoids found in a wide range of red, orange, yellow and green vegetables. This research echoed an earlier study, which showed a reduction in ovarian cancer risk of greater than 50 percent amongtop vegetable consumers.
Although the research is promising, for now women are best advised not to focus on a single potential link highlighted in one or two studies, but to follow current guidelines to lower overall cancer risk. General recommendations include following a diet that provides a wide variety of vegetables and other plant-based foods, exercising regularly and controlling weight.