You may have heard these natural nutrition factors called vitamin P. The more than 800 flavonoids in plants, better known as phytochemicals, may help fight cancer and heart disease. A recent study of almost 10,000 men and women in Finland found that the risk of lung cancer went down as intake of flavonoid-rich foods went up.
Red wine and grape juice, for example, contain significant levels of flavonoids that act as antioxidants, protect against LDL oxidation, and inhibit platelet aggregation, thereby providing protection against heart disease. The following are some of the most studied flavonoids.
Wild blueberries are exceptionally rich in this group of flavonoids, which is responsible for their intense blue color.
They are also found in the reddish pigments in many fruits, such as strawberries, cherries, cranberries, raspberries, grapes, and black currants. More than 100 studies worldwide have looked at the potential health benefits of anthocyanins. They appear to have the ability to inhibit cholesterol synthesis, thus providing protection against heart disease. And proanthocyanin, another flavonoid component of wild blueberries, inhibits an enzyme involved in cancer promotion.
This is the most abundant flavonoid in grapefruit. It may provide protection against cancer by triggering cancer-fighting enzymes in the body. But it can also have strong interactions with some prescription drugs. Researchers have discovered that drinking grapefruit juice with certain drugs prescribed for the heart and for high blood pressure can trigger some pretty frightening side effects, including rapid pulse, irregular heartbeat, dizziness, and flushing.
They believe it's the flavonoids, most likely naringin, that increase the drugs' potency and make them potentially dangerous. But there's an easy solution -- don't take your meds with grapefruit or grapefruit juice. This phytochemical is found in many fruits, vegetables, and grains. Quercetin is the major flavonoid in the western diet. Rich sources are red and yellow onions, kale, broccoli, red grapes, cherries, apples, and cereals.
Like its flavonoid relatives in red wine and tea, it is thought to protect against heart disease via its antioxidant powers. Translation: It prevents the damage to LDLs (low-density lipoproteins, the "bad" cholesterol) that makes them dangerous to artery walls. It may also have anticancer activity.
On the next page, learn about phytonutrient supplements and their role in preventing disease.