Antioxidants are substances that can prevent or slow damage to cells caused by free radicals; unstable molecules that the body produces as a reaction to environmental and other pressures. Antioxidants neutralize excess free radicals to protect cells, prevent illness and reduce inflammation. Oxidative stress has been implicated as a mechanism underlying major psychiatric disorders, as the brain has comparatively greater vulnerability to oxidative damage. 

Oxidative stress is an imbalance between free radicals and antioxidants in the body. Free radicals are oxygen containing molecules with an uneven number of electrons. The uneven number allows them to easily react with other molecules. Free radicals can cause large chain chemical reactions in the body because they react so readily with other molecules. These reactions are called oxidation. 

Oxidation is a normal process that takes place in the body. Oxidative stress, on the other hand, occurs when there’s an imbalance between free radical activity and antioxidant activity. When functioning properly, free radicals can help fight off pathogens, which can lead to infections. When there are more free radicals present than can be kept in balance by antioxidants, the free radicals can start doing damage to fatty tissue, proteins and DNA in the body. 

Because lipids, proteins and DNA make up a large part of the body, excess free radicals are associated with damage all over the body. Studies show that the brain is particularly at risk. A large body of research has demonstrated that antioxidants can help protect the brain and other parts of the body from this type of damage. 

There is substantial evidence linking oxidative stress and the antioxidant defense system with the development of neuropsychiatric disorders, including depression. Equally important, researchers have found that major depression is correlated with a lowered total antioxidant state. 

Antioxidants are known to play a major role in modifying inflammation throughout the body and they help to fight depression due to their anti-inflammatory effect. Although there’s no way surefire way to stop excess free radicals completely, you can lessen their destructive effect by eating foods rich in antioxidants, including the following:

  • Beta-carotene: apricots, broccoli, cantaloupe, carrots, collards, peaches, pumpkin, spinach, sweet potato
  • Vitamin A: apricots, cantaloupe, carrots, collard greens, kale, spinach, sweet potatoes, winter squash
  • Vitamin C: blueberries, broccoli, grapefruit, kiwi, oranges, peppers, potatoes, strawberries, tomato
  • Vitamin E: margarine, nuts and seeds, vegetable oils, wheat germ
  • Herbs and spices: turmeric, cinnamon, clove, oregano, thyme, sage, rosemary
  • Beverages: coffee, bitter beers, green tea

You may wonder, if antioxidants can help with depression, can’t I just take an antioxidant supplement? Unfortunately, it’s not that easy. According to the research, antioxidant supplements don’t have the same protection from depression as food sources. While plant foods and food-derived phytochemicals have been associated with health benefits, antioxidants from dietary supplements appear to be less beneficial. Of course, antioxidants can be taken in the way of supplements and there will be some benefit. Still, it’s best to get as much as possible from food sources. By eating a whole foods diet with lots of fruits and vegetables, you’ll be more apt to get a healthy spectrum of antioxidants. 

It’s impossible to completely avoid free radical exposure and oxidative stress. However, there are things you can do to minimize the effects of oxidative stress on your body. The main thing you can do is to increase your levels of antioxidants and decrease your exposure to free radicals in the environment. Some sources of free radicals include the following: 

  • Pesticides
  • Chemicals from cleaners
  • Cigarette smoke
  • Excessive exercising
  • Ozone
  • Pollution
  • Radiation

Some foods contribute to free radical production, adding to your body’s burden. These include sugar, unsaturated fats and oils, some cooked and processed meats, alcohol and even antioxidant supplements. This is because doses of antioxidants that are too high can actually have a prooxidant effect. 

In sum, an antioxidant supplement treatment may be useful as an adjuvant therapy for patients with stress-induced psychiatric disorders. Anxiety and depression are the most common forms of stress-induced psychiatric disorders. To combat the biochemical changes which occur as a result of stress, there is antioxidant defense in the biological system. Antioxidants like vitamin E, vitamin C and beta-caro-tene are thought to act as secondary non-enzymatic defense against oxidative stress and its potential negative effects.

Randi Fredricks, Ph.D.


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