Source: Best Health Magazine, January/ February 2009
Known for mopping up body-damaging free radicals, antioxidants’found in fruit, vegetables and tea, for example’are increasingly being heralded as health ‘good guys.’
The ‘bad guys’ are free radicals, the by-products of oxidation. Here’s why: Our cells use oxygen to produce energy, and other essential enzymes in our bodies need it to function. But just as oxidation causes a bicycle to rust over time, this process damages not only cell membranes, but also proteins, lipids and DNA (and damage to DNA can trigger cancer). The by-products of this oxidation process are free radicals.
What free radicals do to our bodies
Our bodies can cope with some free radicals; we actually need them to fight infection, stop tumour cells from growing and help repair our tissues. However, as we get older and our built-in antioxidant defence system wears down, we can have too many free radicals. (In fact, it’s long been known that the aging process itself is due to the oxidation of our cells.) Stress, sunlight, alcohol and pollution make it tough for our bodies to fight them off. Smoking produces them in the lungs, where they then enter the body’s circulation system. Free radicals can cause deterioration of the eye lens, inflammation of the joints or arthritis and damage to nerve cells in the brain. They also play some role in heart disease. When oxygen is added to LDL (‘bad’) cholesterol, fatty plaques build up on artery walls. This atherosclerosis can eventually block blood flow to the heart. The best way to avoid heart disease is to limit free radicals. Ways to do that include quitting smoking, avoiding stress and atmospheric pollutants, and eating a varied, healthy diet, including foods containing antioxidants.
Antioxidants and your health
There are different types of antioxidants, including vitamins A, C and E; minerals such as copper, zinc and selenium; phytochemicals from plants, including anthocyanins, lycopene and flavonoids; and zoochemicals in animal products. Antioxidants produce the bright colours in fruit and vegetables; the flavour in foods such as tea, coffee and extra-virgin olive oil; and the bitter taste of dark chocolate.
We’re only just starting to understand the science of how boosting our supply of antioxidants relates to our health. What we do know from population studies is that people who eat a lot of fruit and vegetables live longer. Tests in the lab indicate that some antioxidants may prevent specific diseases: Flavonoids found in green tea are thought to be behind the low rates of cardiovascular disease in Japan, and lutein, an antioxidant found in vegetables such as spinach and corn, protects against deterioration in the eye’s lens.
Is it better to get antioxidants from food or from supplements? Studies seem to indicate that making diet your primary source of antioxidants is best, but if you’re not getting enough from food, then you should definitely use supplements. (Read ‘Vitamins and minerals 101’ for our comprehensive breakdown of why you need them and how much you should be getting daily.)
Get antioxidants into each meal
Canada’s Food Guide recommends that women age 19 to 50 eat seven to eight servings of vegetables and fruit each day, suggesting at least one dark green and one orange vegetable. As antioxidants give some foods brighter colours than others, choose oranges or berries over honeydew melon, and romaine over iceberg lettuce. You could also have a small piece of dark chocolate once a day, and drink green tea rather than coffee. Include antioxidant-rich foods in every meal: Eat slices of tomato on toast, or fruit with your cereal at breakfast, and add salad to your lunch. Juices can provide several servings of fruit or vegetables in one glass, but watch the extra calories. (Or whip up an antioxidant-rich drink). The key is variety, so that you obtain as many different antioxidants as possible.