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Antioxidants Can Impair Muscle Function

Are Antioxidants Damaging our Health?

antioxidantsWe generally consider antioxidants to be “good”. Their health benefits are said to be numerous: they aid the body in fighting infections, they slow the aging process, and they help to ward off chronic diseases such as atherosclerosis and cancer. Antioxidants, which are naturally occurring in many foods, such as vegetables, fruits, and legumes, can prevent or slow the oxidative damage to the body by fighting free radicals. Some vitamin and minerals with antioxidant properties include:

Free radicals are chemicals that are produced when the body is exposed to ‘stressful’ toxins such as pollution, cigarette smoke, and alcohol. More innocuous elements such as sunlight and exercise, interestingly, also generate free radicals.

So, knowing this, we might logically conclude that the more antioxidants we get, the better our health. But what if antioxidants are actually causing more harm than good?

A few experts are claiming just that. One hallmark study performed on rats at Kansas State’s Cardiorespiratory Exercise Laboratory claims that antioxidant supplements may lead to impaired muscle function. They found that some antioxidants block the processes of some necessary oxidants, such as hydrogen peroxide. Hydrogen peroxide acts as a vasodilator, and if blocked by antioxidants, the researchers hypothesize that the muscles won’t receive the blood flow essential for muscle function and repair. Furthermore, they discussed the potential for antioxidants to “suppress key signaling mechanisms that are necessary for muscle to function effectively.”

Supplementing with antioxidants might lead to cancer

One notorious study done in the mid-1990’s was forced to stop due to the increased incidence of antioxidant-related cancer and mortality. The Beta-Carotene and Retinol Efficacy Trial looked at the effects of antioxidant supplementation (β-carotene and retinyl palmitate) on 18 314 participants who were at a higher risk of cancer, and lung cancer especially, as a result of asbestos exposure and smoking. The researchers had to stop the trial because those undergoing the antioxidant intervention were discovered to have a 28% increase in incidence of lung cancer and a 17% increase in mortality overall.

The Science is Divided

As happens frequently in scientific studies, findings are contradictory and inconclusive. Some sources tout the extraordinary benefits of antioxidants, while others tell us that, at best, antioxidants are ineffective, and, at worst, life-threatening.

We would recommend to always exercise caution when trying a new supplement, whether or not it is said to be an “antioxidant”. If possible, eat a varied, whole food diet from which you can naturally receive all essential nutrients. Supplements can be powerful substances, and while many do good, some can seriously damage your health. So, do your research! And please feel free to contact the experts at Infofit if you have any questions about changing your nutrition or exercise regimen.

Wishing you all the best on your journey to optimum health!

Written by Theresa Faulder, Master’s in English, Certified Personal Trainer and Infofit fitness blog writer.

Works Cited

Add antioxidants to your diet. (2019, November 23). Retrieved October 19, 2020, from

Antioxidants aren’t always good for you and can impair muscle function, study shows. (2010, January 28). Retrieved October 19, 2020, from

Antioxidants. (2019, November 14). Retrieved October 19, 2020, from

Hanna, N. (2006). The Beta-Carotene and Retinol Efficacy Trial: Incidence of Lung Cancer and Cardiovascular Disease Mortality During 6-Year Follow-up After Stopping β-Carotene and Retinol Supplements. Yearbook of Oncology,2006, 14-15. doi:10.1016/s1040-1741(08)70014-9

Yavari, A., Javadi, M., Mirmiran, P., & Bahadoran, Z. (2015). Exercise-Induced Oxidative Stress and Dietary Antioxidants. Asian Journal of Sports Medicine, 6(1). doi:10.5812/asjsm.24898

Certified Sports Performance and Fitness Nutrition Specialist

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