Rainbow on a Plate

A lot of product labels will try to entice you with the promise of antioxidants. But while we know antioxidants are good for us, what do they do exactly? Simply put, antioxidants prevent oxidation, a natural chemical reaction with oxygen. Oxidation causes iron to rust and turns some vegetables (like apple slices or potatoes) brown. It is also required for burning. For example, when you burn wood at a campfire, carbon in the wood reacts with oxygen, creating energy (heat), carbon dioxide and steam. In a similar way, our bodies use oxygen to burn (metabolize) the food we eat, giving us energy and producing carbon dioxide and water vapor (which we breathe out

Carrot contain lots of orange antioxidants. Credit: Steven Depolo, FlickrCC
Carrot contain lots of orange antioxidants. Credit: Steven Depolo, FlickrCC

But some natural “free radical” compounds react with oxygen, damaging cells. In chemistry, a free radical is a molecule with an unpaired electron. The free electron makes these molecules highly reactive, thus prone to oxidation. In the human body, free radical compounds are responsible for the effects of aging and may contribute to chronic diseases like cancer, Alzheimer’s and heart disease.

“Antioxidants guard against cellular damage which occurs as a result of free radicals in the body,” says Dr. Carolyn Dean, medical director of the Nutritional Magnesium Association. Dr. Joy Dubost, a spokesperson for the American Dietetic Association (eatright.org) with expertise in functional foods including antioxidants, explains that “free radicals are formed in your body from external forces like pollutants or the sun. They can also be internally made. For example, you produce free radicals when you exercise or when you’re exposed to viruses and bacteria. Too many free radicals can damage cells and produce a low inflammation state, which can lead to disease. Antioxidants combat those free radicals

Plant Power

So, what are these antioxidant compounds that prevent oxidation? They are natural substances found in plants and include enzymes, vitamins and some minerals. Dr. Dubost explains that plants are the best source of antioxidants. “There are more than 8,000 plant chemicals that behave as antioxidants when you consume them,” she says. These include fruits, vegetables, herbs, spices, nuts, fungi (mushrooms), tea, cocoa, and essential oils. Some of the best known antioxidants are vitamins like vitamin C, vitamin E, and beta carotene (a substance our body uses to make vitamin A) and minerals (like magnesium). Others are lycopene, lutein and zeaxanthin

Dr. Dubost adds that “not all antioxidants behave in the same way. They all have different mechanisms. Different colored fruits and veggies all contain different antioxidants, so we really need to eat a variety of plants to get all of them.

For example, carotenoids are orange antioxidants. They are found in carrots, sweet potatoes and mangoes. Green and yellow antioxidants like lutein and zeaxanthin are linked to reducing the risk of atherosclerosis—or hardening of the arteries—and cataracts. These are found in yellow corn, avocadoes and melons like honeydew. Green cruciferous vegetables like broccoli or kale contain indoles, antioxidants that help fight cancer. Powerful purple antioxidants include anthocyanidins, which help prevent inflammation and may protect against arthritis and heart disease. Purple and blue foods include blackberries, blueberries and eggplant. To get all the antioxidants we need, we should consume a variety of plant foods—fruits and vegetables, as well as herbs, beans and grains.

No Supplement Solution

Chemical food preservatives like BHT which is added to food packaging to extend shelf life, also prevent oxidation. But, says Dr. Dubost, “BHT behaves as an antioxidant in that food, but is not necessarily protective for our bodies when we consume it.”

And it is more beneficial when antioxidants come from food sources as opposed to pills. In fact, says Baltimore internest Dr. Dana S. Simpler, “Johns Hopkins published a study last fall showing that Vitamin E supplements actually increase, rather than decrease, all causes of death. The reason is not yet well understood, but our bodies may have natural antioxidant pathways that somehow get disabled or blocked when we take antioxidant vitamins in pill form. This is not thought to be true when we get antioxidants from fruits, vegetables and other whole foods.”

An ideal diet involves plenty of whole, unprocessed plant foods rich in antioxidants. One of the easiest ways to ensure you’re getting the full spectrum of antioxidants is to fill your plate with foods of many colors

YVONA FAST has two passions: cooking and writing. She writes a weekly column, “North Country Kitchen” and can be reached at wordsaremyworld.com.