Foods to Reduce Free-Radical Damage

With the increase in environmental toxins in our food, air, soil and water, we are more susceptible than ever to the potential damage to our body. As we age, we are more likely to experience intercellular damage resulting in degenerative disease.

Aging itself is connected with the instability of the body’s chemical byproducts, or free radicals1. These electrically charged molecules are a normal part of the body’s functioning, and have many positive effects on the body2. However, free radicals that build up in the body over time create dysfunction1 and damage cell membranes2. In particular, reactive oxygen free radicals are a major contributor to chronic disease3. Envision natural elements causing metals to rust. 

Antioxidants are the body’s force for combatting free radicals. Antioxidants reduce oxidative damage, support the body’s defense systems, contribute to longevity, and support cell maintenance and DNA repair3. Every physiological system relies on antioxidants.

Unfortunately, pollutants, chemicals, stress, aging, alcohol, medications and The Standard American Diet reduce antioxidant status4. Resultant damage is linked to age-related neurodegenerative diseases like Alzheimer’s and Parkinson’s, the prevalence of which increases with aging5 and neuroendocrine diseases like some cancers, affecting mostly women4.

Increased oxidative toxicity and poor antioxidant status is called The Aging Theory of Oxidative Stress4, meaning that the damage defeats the insufficient antioxidant potential. When we alleviate oxidative stress, we reduce risk of related diseases3. This concept highlights the importance of preventative health and lifestyle factors4.

Glutathione is the matriarch of antioxidants and made within the body. It supports cardiovascular and immune systems, eye and brain health, and the aging process.  Unfortunately, glutathione levels decline as we age and low levels are associated with cancer, systemic inflammation, Alzheimer’s and Parkinson’s, and a suppressed immune system6.

So what can we eat to reduce free radical damage?

While whole foods do not contain glutathione itself, its amino acids – glutamate, cysteine and glycine – are widely available from both plant and animal sources. The nutrients that are essential to glutathione function include sulfur, alpha-lipoic acid, B vitamins (including biotin and folate)7,8. Cruciferous vegetables, garlic and onions are high in sulfur and some are also high in alpha-lipoic acid. Like amino acids, B vitamins are in a wide range of foods.

Other nutrients are fundamental in the production of glutathione and are revered for their ability to scavenge free radicals. These antioxidants include vitamins E and C found in nuts, seeds, fruits and vegetables, and the mineral selenium found in Brazil nuts, some fish, meat and dairy products.

Additionally, plant-based foods contain bioactive phytonutrients, which exhibit high antioxidant activity on cells, both individually and synergistically. Key phytonutrient antioxidants include carotenoids, flavonoids, anthocyanins, lycopene, lutein, genistein and resveretrol3.

A short list of foods of antioxidant foods we should all be eating include plenty of brightly colored fruits and vegetables – leafy greens; cruciferous; sweet potatoes, carrots and mangoes; tomatoes, watermelon and pink grapefruit; wild blueberries, goji berries, elderberries, beets and red cabbage. Nuts, seeds, beans and (my favorites) dark chocolate and green tea exhibit high levels of antioxidants9,10. Furthermore herbs (cumin, parsley, cilantro, basil) and spices (cloves, cinnamon, turmeric, cumin, cayenne) show some of the most potent levels of antioxidants9, though intake is typically small.

In conclusion, to offset the burden of the world’s toxins: 1. Eat high amounts of colorful, sustainably raised whole foods, especially from plant sources; 2. Cook at home using toxin-free kitchen methods (metals steal sulfur from enzymes and other compounds in our body that otherwise protect cells6; 3. Ensure optimal gut function for digestion, nutrient absorption, and elimination.



1Denham Harmon, 1916-2014. (2015). The Pauling Blog. Retrieved from

2Bowen, R. (n.d.). Free radicals and reactive oxygen. Vivo pathophysiology: Colorado State University. Retrieved from

3Carlsen, M. H., Halvorsen, B. L., Holte, K., Bøhn, S. K., Dragland, S., Sampson, L., … Blomhoff, R. (2010). The total antioxidant content of more than 3100 foods, beverages, spices, herbs and supplements used worldwide. Nutrition Journal9, 3.

4Gonçalves Mota, M. P., Santos, Z., Soares, J., Pereira, A., Fonseca, S., Peixoto, F., Gaivão, I., … Oliveira, M. (2017). Oxidative Stress Function in Women over 40 Years of Age, Considering Their Lifestyle. Frontiers in endocrinology8, 48. doi:10.3389/fendo.2017.00048

5Kim, G. H., Kim, J. E., Rhie, S. J., & Yoon, S. (2015). The Role of Oxidative Stress in Neurodegenerative Diseases. Experimental neurobiology24(4), 325-40. 

6Williams, D. (n.d.). NAC: A glutathione booster. Dr. David Williams. Retrieved Oct. 16, 2018 from

7Axe, J. (2015). 9 ways to boost glutathione. Dr. Axe: Food is Medicine. Retrieved from

8Hyman, M. (n.d.). What is glutathione and how do I get more of it? Dr. Hyman. Retrieved from

9Axe, J. (2018). Top 10 high antioxidant foods. Dr. Axe: Food is Medicine. Retrieved from

10Weil, A. (2010). ORAC: Scoring antioxidants? Weil. Retrieved from