In everyday life, our bodies generate free radicals. Normally, the body can handle free radicals, but if antioxidants are unavailable, or if the free radical production becomes excessive, cellular damage can occur. Free radicals are the major cause of aging and declined health. Antioxidants bind with these free radicals, rendering them powerless to help you maintain optimal health.
Free radicals cause cell mutations, damage immune function, cause wrinkles and aging and are a contributing cause behind many diseases including cancer, heart disease, arthritis, Alzheimer’s disease, Parkinson’s disease, and others. Free radical damage is a factor behind almost every known disease according to some researchers.
Free radicals are caused by the body’s own natural processes. Free radical excesses are further created from the addition of things like toxins or radiation or poor digestive function. Disease tends to create free radicals. We are constantly creating free radicals at an astonishing speed.
The antidote to free radicals is the antioxidant. We make some antioxidants and some are traditionally supplied in the diet (fruits, vegetables). Environmental influences have increased the need well beyond what our bodies are capable of producing, and even beyond diet.
What are free radicals?
We’re made up of trillions of cells. They come together to form tissues, and tissues come together to form organs. The free radical/antioxidant story couldn’t really be told until cellular biology matured as a science, which wasn’t all that long ago. What happens within these cells may determine how long you live, and whether you live your life fully or with the burden of disease.
Cells have smaller units called atoms. Within the atom is a nucleus surrounded by pairs of electrons. But unlike a stable molecule in which every atom is ringed by pairs of electrons, free radicals carry an unmated electron that is looking to pair up with another. By snaring an electron from a neighboring molecule (which then makes that molecule a free radical), it can set off a chain reaction that wrecks havoc on cells. This process damages cell structures and DNA. This is devastating to a cell. Free radicals are constantly forming everywhere in the body at an astonishing rate.
Bruce Ames, a well-known scientist in the field of antioxidants, estimates that just one cell in the human body is hit about 10,000 times a day by a free radical. If that’s multiplied by the trillions of cells in the body the magnitude of this activity is tremendous.
How are free radicals formed?
Oxygen is the basis for the formation of free radicals. We require large amounts of it for metabolism, which is breaking down nutrients for growth and energy. This energy is essential for such processes as breathing, thinking, digesting your food and having a beating heart. This is natural. The body and immune system uses some free radicals in a positive way.
Additional free radicals can be caused by environmental sources like tobacco smoke, oil fumes, chemicals, pollutants, radiation, the sun or ozone. Disease creates free radicals. So does exercise.
Free radical proliferation can also be caused by a lack of antioxidants in the diet, or the inability of the body to produce enough of them.
How do antioxidants help?
When an antioxidant encounters a free radical it freely gives up an electron of its own which satisfies the free radical and stops the out of control damage. This makes the antioxidant a free radical because it’s now an electron short. However, the chain reaction is stopped because the newly created free radical made from the antioxidant is very weak and unlikely to do further harm.
Antioxidants for Immunity: Where to Find Them
Adding more fruit and vegetables of any kind to your diet will improve your health. But some foods are higher in antioxidants than others. The three major antioxidant vitamins are beta-carotene, vitamin C, and vitamin E. You’ll find them in colorful fruits and vegetables – especially those with purple, blue, red, orange, and yellow hues. To get the biggest benefits of antioxidants, eat these foods raw or lightly steamed; don’t overcook or boil.
- Beta-carotene and other carotenoids: Apricots, asparagus, beets, broccoli, cantaloupe, carrots, corn, green peppers, kale, mangoes, turnip and collard greens, nectarines, peaches, pink grapefruit, pumpkin, squash, spinach, sweet potato, tangerines, tomatoes, and watermelon.
- Vitamin C: Berries, broccoli, Brussels sprouts, cantaloupe, cauliflower, grapefruit, honeydew, kale, kiwi, mangoes, nectarines, orange, papaya, red, green or yellow peppers, snow peas, sweet potato, strawberries, and tomatoes.
- Vitamin E: Broccoli, carrots, chard, mustard and turnip greens, mangoes, nuts, papaya, pumpkin, red peppers, spinach, and sunflower seeds.
Other super foods that are rich in antioxidants include prunes, apples, raisins, berries, plums, red grapes, alfalfa sprouts, onions, eggplants, and beans.
Vitamins aren’t the only antioxidants in food. Other antioxidants that may help boost immunity include zinc (found in oysters, red meat, poultry, beans, nuts, seafood, whole grains, fortified cereals, and dairy products) and selenium (found in Brazil nuts, tuna, beef, poultry and fortified breads, and other grain products).
Antioxidant Super Foods: How Much Do You Need?
For optimal health and immune functioning, you should eat the recommended dietary allowance (RDA) of the antioxidant vitamins and minerals. That’s the amount of a vitamin or nutrient that you need to stay healthy and avoid a deficiency.
Here are the RDAs for some antioxidants:
- Zinc: 11 milligrams for men, 8 milligrams for women. If you are a strict vegetarian, you may require as much as 50% more dietary zinc. That’s because your body absorbs less zinc when you have a diet rich in plant-based foods.
- Selenium: 55 micrograms for men and women.
- Beta-carotene: There is no RDA for beta-carotene. But the Institute of Medicine says that if you get 3 milligrams to 6 milligrams of beta-carotene daily, your body will have the levels that may lower risk of chronic diseases.
- Vitamin C: 90 milligrams for men, 75 milligrams for women. Smokers should get extra vitamin C: 125 milligrams for men and 110 milligrams for women.
- Vitamin E: 15 milligrams for men and women.
How Foods Boost Immunity
Can’t you get antioxidants from taking a vitamin or a supplement? Yes, but you may be missing out on other nutrients that could strengthen the immune system. Foods contain many different nutrients that work together to promote health. For example, researchers delving into the mysteries of fruits and vegetables and the complex antioxidants they contain have discovered benefits of:
- Quercetin: a plant-based chemical (phytochemical) found in apples, onions, teas, red wines, and other foods. It fights inflammation and may help reduce allergies.
- Luteolin: a flavonoid found in abundance in celery and green peppers. It also fights inflammation and one study showed it may help protect against inflammatory brain conditions like Alzheimer’s.
- Catechins: a type of flavonoid found in tea. Catechins in tea may help reduce risk of heart disease, cancer, and Alzheimer’s disease.
If you can’t get enough antioxidants in your diet by eating fresh produce, some experts recommend taking a multivitamin that contains minerals, too. But be cautious about taking individual immune system supplements to boost immunity. With antioxidants, as with most anything, moderation is key. Vitamins A and E, for example, are stored in the body and eliminated slowly. Getting too much can be toxic.