- Aynsley Fisher
Antioxidants— Best Defense Against Cellular Damage
Free radicals are a fact of life. They are all around us— in the air we breathe, the food we eat and as a product of sun exposure. They are also formed as a byproduct of converting the food we eat into energy.
Free radicals come in many shapes, sizes, and chemical configurations. Electron thieves, they steal electrons from any nearby substances. This electron theft changes the “loser’s” structure or function, altering the cell’s instructions coded in a strand of DNA. The damage generated by free radicals to cell membranes and DNA may contribute to aging and health conditions, including heart disease and cancer.
Antioxidants work by slowing or even preventing the harmful activity of ‘free radicals’ in our bodies. Antioxidant nutrients are the body’s defense against free radical damage and work by giving electrons to free radicals without turning into electron- scavenging substances themselves. There are hundreds, probably thousands, of different substances that can act as antioxidants. The most familiar ones are vitamin C, vitamin E, beta-carotene, and other related carotenoids, along with the minerals selenium and manganese. They’re joined by glutathione, coenzyme Q10, lipoic acid, flavonoids, phenols, polyphenols, phytoestrogens, and many more.
Carotenoids and Beta-carotene Beta-carotene is a phytonutrient antioxidant (and member of the carotenoids) found in plants characterized by vibrant colors and is converted to vitamin A inside the body. The richest sources of beta-carotene are yellow, orange, and green leafy fruits and vegetables (such as carrots, spinach, lettuce, tomatoes, sweet potatoes, broccoli, cantaloupe, and winter squash). In general, the more intense the color of the fruit or vegetable, the more beta- carotene it has.
Vitamin A Vitamin A is a fat-soluble vitamin that plays a role in many important body processes including immune system function, growth, bone formation, reproduction and wound healing. It helps cells reproduce normally, a process called cell differentiation. It’s essential for good vision, the healthy development of an embryo and fetus and helps keep skin and mucous membranes that line the nose, sinus and mouth healthy.
Vitamin A comes from two sources:
Retinoids From animal sources and includes retinol
Carotenoids From plants and includes beta- carotene
The body converts beta-carotene to vitamin A. Major carotenoids, including lycopene, lutein, and zeaxantuin, have important biological properties, including antioxidant and photo-protective activities.
Vitamin C An antioxidant along with vitamin E, beta-carotene and other plant-based nutrients, vitamin C is a water-soluble vitamin. Since our bodies don’t store it, we have to get what we need from food.
Vitamin C is essential for the growth and repair of tissues in all parts of your body. It helps the body make collagen, an important protein used to make skin, cartilage, tendons, ligaments, and blood vessels. Vitamin C is needed for healing wounds, and for repairing and maintaining bones and teeth. It also helps the body absorb iron from nonheme sources.
Excellent sources of vitamin C include oranges, green peppers, watermelon, papaya, grapefruit, cantaloupe, strawberries, kiwi, mango, broccoli, tomatoes, Brussels sprouts, cauliflower, cabbage, and citrus juices or juices fortified with vitamin C. Raw and cooked leafy greens (turnip greens, spinach), red and green peppers, canned and fresh tomatoes, potatoes, winter squash, raspberries, blueberries, cranberries, and pineapple are also rich sources of vitamin C. Vitamin C is sensitive to light, air, and heat, so you'll get the most vitamin C if you eat fruits and vegetables raw or lightly cooked.
Vitamin E An antioxidant, vitamin E is a fat-soluble vitamin found in many foods, fats and cold-pressed oils. Dietary sources include: eggs, nuts, seeds, wheat germ, dark leafy greens, whole grains, sweet potatoes, avocado, asparagus to name a few. Vitamin E is also important in helping your body make red blood cells, and it helps the body use vitamin K.
Selenium Selenium is an essential mineral and antioxidant found in small amounts in the body. It works as an antioxidant, especially when combined with vitamin E. Good sources of selenium include brewer's yeast and wheat germ, butter, fish (mackerel, tuna, halibut, flounder), shellfish (oysters, scallops, and lobster), garlic, whole grains, sunflower seeds, and Brazil nuts. Selenium levels in food depend on how much selenium was in the soil where the food was grown. Selenium is destroyed when foods are refined or processed. Eating a variety of whole, unprocessed foods is the best way to get selenium in your diet.
Manganese Manganese is a trace mineral that is present in tiny amounts in the body. It is found mostly in bones, the liver, kidneys, and pancreas. Manganese helps the body form connective tissue, bones, blood clotting factors, and sex hormones. It also plays a role in fat and carbohydrate metabolism, calcium absorption, and blood sugar regulation. Manganese is also necessary for normal brain and nerve function.
Manganese is a component of the antioxidant enzyme superoxide dismutase (SOD), which helps fight free radicals. Free radicals occur naturally in the body but can damage cell membranes and DNA. They may play a role in aging, as well as the development of a number of health conditions, including heart disease and cancer. Antioxidants can help neutralize free radicals and reduce or even help prevent some of the damage they cause. Low levels of manganese in the body can contribute to infertility, bone malformation, weakness, and seizures. Found in whole grains, nuts, and seeds, manganese is readily available in our diet.