A large apple or banana, a cup of broccoli, or a medium-size salad each counts as two servings. Our advice is based on that from the National Cancer Institute, which recommends at least five servings of fruits or vegetables. The USDA, in its food pyramid, recommends at least three to five vegetables and two to four fruit servings. The more food you eat each day, the more fruits and vegetables you should aim for. Five servings might be the minimum for, say, a woman consuming 1,500 calories a day, but nine would be a better goal for a man eating 3,000 calories.
Some studies have shown that flaxseed can reduce some kinds of tumors in lab animals.
But higher doses were found to have the opposite effect, boosting hormone levels and increasing cell proliferation. It's thought that flaxseed may have an anti-cancer effect because it's very rich in lignans. In the process of digestion, bacteria convert lignans into estrogen-like substances that may affect tumors. Flaxseed oil, however, usually doesn't contain lignans, though some processors do add some lignans back into the oil. But don't eat flaxseed because you think it will protect your prostate.