Antioxidant Power: Food Can Do It

By Karen Collins, M.S., C.D.N, American Institute for Cancer Research

Is healthy eating enough? Recent studies from Johns Hopkins University, Tufts University and USDA found that simply adding a few more servings of fruits and vegetables each day can provide enough antioxidants to offer significant protection against a process linked with heart disease and cancer.

Antioxidants work by blocking the actions of certain highly reactive substances that can damage body cells and either start the process of cancer development themselves or make cells more vulnerable to other cancer-causing substances. Research in recent years has also found a link with heart disease: the clogging of blood vessels by fatty deposits is not just related to the amount of fatty substances in the blood, but also to how much those fats have been changed into a more dangerous form by a process called oxidation. Antioxidants block that reaction, too.

Many people hearing of antioxidants, think only of certain antioxidant vitamins (C, E and beta carotene), but a joint Tufts University/USDA study does not support that notion. When subjects increased their fruit and vegetable consumption to 10 standard-size servings a day, laboratory tests showed that their ability to resist damage from oxidation increased significantly. Yet analysis showed that carotenoids and vitamins C and E provided only a small part of this resistance. The researchers reported that a wide variety of natural phytochemicals in fruits and vegetables seem to play an important role. The study also found that resistance peaked with ten servings and could not be increased further.

Circulatioin's report on a study at John Hopkins University identified two ways to reduce Oxidative damage. As in the previous study, increased fruits and vegetables to nine or ten servings a day showed greater resistance to oxidation. Another test showed that combining this strategy with eating a healthfully low level of fat reduced oxidation damage even further.

While public education campaigns are urging Americans to increase their fruits and vegetables to reach “Five a Day” these studies managed to boost consumption to nine or ten servings per day. Some may think it's easier to just shoot for the five servings and add a supplement to get extra antioxidants. But remember that one of these studies' analysis showed that only a small portion of the antioxidant improvement was vitamin - or carotenoid - related. Produce's naturally-occurring phytochemicals seems to play a key role, and they haven't even all been discovered yet!

This level of fruit and vegetable consumption isn't quite as awesome a feat as it may sound at first: a half-cup of cooked or chopped raw fruit or vegetables, a cup or raw leafy greens, quarter-cup of dried fruit, and a six-ounce glass of juice all count as one serving. So as long as you don't fill up on too much meat or sweets, or overdue the pasta and bread, you could easily include three servings in each meal. And snacks are a great place to work in some fruit, juice or a raw vegetable.

If you haven't yet reached the goal of five servings of fruits and vegetables a day, don't be overly ambitious -- aim for five first by including some form of produce in each meal. But if you've made it to five servings, consider whether you're ready to push a bit further -- studies like these recent ones suggest that the benefits continue to increase all the way up to ten serving per day. Go for it!