Ask the Dietitian: May 2013
May 2, 2013
"Do I need antioxidant supplements?"
We are continuously bombarded with information regarding antioxidant supplements and the benefits they provide, from preventing cancer, dementia, and heart disease to helping you use those extra few pounds.
But do we really need to take supplements to benefit from antioxidants?
Antioxidants are substances that may protect your cells against free radical damage. Free radicals are produced when your body breaks down food or from environmental exposures like tobacco smoke and radiation. Free radicals can damage cells and may play a role in heart disease, cancer and other diseases.
There are hundreds of different substances that can act as antioxidants.
The most familiar ones are vitamin C, vitamin E, and carotenoids. However minerals such as selenium and manganese as well as polyphenols, including anthocyanins and catechins, and other enzymes such as coenzyme Q10 have antioxidant properties as well.
Antioxidants are often classified using an oxygen radical absorbance capacity, or ORAC value. This measures the antioxidant capacity in a test tube, which does not necessarily translate into its antioxidant activity in the human body.
The U.S. Drug Administration recently removed this database from their website because companies were abusing it to support the health claims of its products.
Still wondering if you should be taking supplements taking supplements to get higher amounts of antioxidants in your diet?
The short answer is no.
Many supplement companies want you to believe that supplements, such as green tea extract or resveratrol, provide the same health benefits as drinking green tea or a glass of red wine.
Research indicates that there may be a variety of compounds within the food acting together to provide the antioxidant activity, not just one compound, such as what you'd find in a pill.
Additionally by consuming excessive quantities of the antioxidant-rich compound you may actually put yourself at risk of the disease you were trying to prevent.
Instead, it is recommended to eat a diet with a variety of foods to provide adequate amounts of various compounds with antioxidant activity.
Citrus fruits are a great source of vitamin C. Vitamin E is found in nuts, seeds and vegetable oils.
Carotenoids are found in a variety of vegetables including red, orange, deep-yellow and some dark-green leafy vegetables, such as tomatoes, carrots, spinach, Brussels sprouts, sweet potatoes, winter squash and broccoli.
By consuming a variety of fruits and vegetables in your diet you will not need supplements.
Aim for two cups of fruit and 2 ½ cups of vegetables daily.
(Editor's Note: Melissa Denton is an inpatient registered dietitian at Tripler Army Medical Center. Ask the Dietitian is a monthly column. Have a question? Email firstname.lastname@example.org.)