Free Radicals and Eating Well


Why you should protect against damaging Reactive Oxygen Species (ROS) such as Free Radicals?

By Anthony Ortiz Rph, CCN


The protective mechanisms in your cell include enzymes that disable the free radicals, such as superoxide dismutase, and glutathione peroxidase. These enzymes require nutrients like the minerals manganese, selenium, and copper, which are present in whole grains. Glutathione is a very important molecule that can destroy free radicals, and it can be obtained directly from the diet, or can be made in your body from nutrients in the diet like the amino acid glycine, and the sulfur-containing amino acid cysteine, which are present in a variety of foods, such as broccoli, garlic and cauliflower. The enzymes involved in energy metabolism also require minerals, like iron, magnesium, copper, selenium, and manganese, which can be obtained from whole foods and vegetables.

Antioxidants are dietary compounds that directly bind to and destroy (quench) free radicals that are oxidants. Much research has shown that green tea is protective against many types of cancer, and the active ingredients in green tea that play this protective role are the catechins, which are antioxidants. Research supports that these food ingredients protect against cancer and other damage in the cell by their antioxidant activities. Vegetables and fruits contain a number of compounds like this, called flavonoids, which can act directly as antioxidants and quench the ROS free radicals. This is thought to be why higher consumption of fruits and vegetables is associated with lower risk of a host of diseases, including cancers and many chronic degenerative diseases. Among their protective actions, micronutrients like vitamin C, the tocopherols (which include vitamin E), and the carotenoids (including beta-carotene, lutein and lycopene) function as antioxidants to protect your cells from damage.

What Can I Do to Support Healthy Cellular Nutrition?


Food provides your cells with the nutrients that serve as their building blocks and protect your cell’s important functions like energy production. By understanding how food and nutrients affect the health of your cells, you not only know what foods are beneficial, but how and why a diet that features nutrient-rich, whole and organically grown foods can promote your optimal health. • Eat foods that nutritionally support your cell’s membranes. Dietary proteins, after being broken down into amino acids and then resynthesized into new proteins, replace protein-containing components in the cellular membrane that have become worn out. Certain amino acids are also used to manufacture the signaling chemicals, such as hormones, that are integral to cell-to-cell communication. Good dietary sources of protein include fish, (preferably wild-caught, cold water fish, since they are also an excellent source of beneficial omega 3 fatty acids), organic eggs, legumes, grains, nuts and seeds, and vegetables. A significant percentage of the essential fatty acids in phospholipids is comprised of omega-3 essential fatty acids. For example, over 35% of phospholipids in the brain and 60% in the eye’s photoreceptors feature the omega-3 fatty acid, docosahexanoic acid (DHA). Therefore, providing the body with adequate levels of these important nutrients can help to ensure proper membrane structure. Good dietary sources of omega-3 essential fatty acids include fish, in particular wild-caught tuna and salmon.


Inositol is a component of membrane phospholipids that are involved in various functions including cellular signaling. Increases in dietary inositol and choline have been found to significantly influence the concentration of membrane phospholipids and support healthy membranes. Good dietary sources of inositol include whole grains; choline is also present in high amounts in egg yolks. 

Provide your body with foods rich in antioxidants.

The vitamin E family, the tocopherols, contains powerful antioxidants that are able to protect both the lipid and protein components in your cell membranes from damage caused by free radicals and other oxidative compounds. Research has suggested that through their powerful antioxidant activity, the tocopherols may be able to protect DNA from the damage caused by oxidative stress. Recent research has focused upon vitamin E’s ability to shield DNA from the damage caused by free radicals generated by cigarette smoking. Smokers with higher levels of chromosomal damage have been found to have lower levels of circulating vitamin E. The antioxidant vitamin E can also protect the mitochondria from the effects of the free radicals produced during ATP manufacture. In addition, supplemental vitamin E seems to support tissue retention of supplemental coenzyme Q10, a critical nutrient for energy production. Good dietary sources of the vitamin E family include wheat germ and wheat germ oil, as well as oils from other grains and legumes, like soy oil. Vitamin C is critical to cellular membrane health since it plays an integral role in recycling vitamin E back to its active form.


Intracellular vitamin C has been found to protect the DNA of many cells, including white blood cells and the eye’s lens, from oxidative damage caused by free radicals and ultraviolet radiation. By regenerating vitamin E back to its active form, vitamin C also plays a role in supporting genetic integrity and as discussed above, in protecting the mitochondria from potential damage by reactive oxygen species, like free radicals. Excellent dietary sources of vitamin C include chili peppers, parsley, broccoli, bell pepper, strawberries, oranges, lemon juice, papaya, cauliflower, kale, mustard greens, and Brussels sprouts.

Research on animals suggests that lipoic acid supplementation increases mitochondrial membrane function and metabolic activity and reduces the potential for oxidative damage. In addition, lipoic acid functions directly as an antioxidant and serves as a cofactor for maintaining the active states of coenzyme Q10 and vitamin E, both of which are important to the integrity of the mitochondria. Dietary sources of lipoic acid include potatoes, carrots, beets and and kohlrabi. Although not recommended since it is also loaded with cholesterol, red meat also contains alpha-lipoic acid. The amino acid cysteine is a precursor for glutathione peroxidase, a powerful antioxidant that helps protect the mitochondria from oxidative damage. The mineral selenium serves to activate the formation of this important antioxidant. Dietary sources of cysteine include legumes, whole grains, and sesame seeds. Excellent dietary sources of selenium include mushrooms, shrimp, salmon, snapper, halibut, calf’s liver, mustard seeds, and pork. 


Provide key nutrients for mitochondrial support and energy production. Vitamin B3 (Niacin), serves as a precursor to NAD+, a compound that is important in the electron transport for energy production, and inhibits DNA strands from rupturing. Supplementation of nicotinic acid (a form of niacin) has been found to reduce DNA damage in human white blood cells. Excellent sources of B3 include salmon, tuna, chicken breast, mushrooms, and yeast. Very good sources include asparagus, tomato, halibut, pork, and calf’s liver. Coenzyme Q10 serves as both a component of the ETC as well as a mitochondrial antioxidant.

Supplementation of Coenzyme Q10 in humans and animals has been shown to beneficially affect the efficiency of mitochondrial energy production and to protect mitochondrial DNA from free radical damage. Good dietary sources of Coenzyme Q10 include oils from nuts, fish and meat. • Support healthy DNA. Folic acid is critical to our genetic integrity since a deficiency of this nutrient can cause the incorporation of an incorrect nucleotide into DNA that will cause the strand to break. In addition, folic acid plays an important role in the process of methylation, which is necessary for proper genetic expression. In addition to folic acid, vitamin B6 and vitamin B12 are also involved in methylation reactions that are critical for maintaining proper genetic expression. Deficiencies of these vitamins are related to increased homocysteine levels that have been found to have a negative effect on cellular methylation. Excellent dietary sources of folate include spinach, parsley, broccoli, beets, turnip greens, asparagus, romaine lettuce, yeast, calf’s liver, and lentils. Excellent dietary sources of B6 include bell peppers, turnip greens, cauliflower, garlic, tuna, mustard greens, and kale. Excellent dietary sources of B12 include calf’s liver, snapper, salmon, shrimp, scallops, beef, lamb, and halibut. Many of the enzymes that are involved in the repair and replication of DNA have zinc as a component. Zinc supplementation has been found to prevent radiation-induced DNA strand breakage. Excellent sources of zinc include: calf’s liver and mushrooms. Very good sources include: beef and yeast. Good sources include: turkey, pork, pumpkin seeds, and adzuki beans.


 Reduce intake of foods to which you are allergic or intolerant. Certain people have allergenic and hypersensitivity reactions to specific foods. These reactions, which involve an array of different immune system messengers, can disrupt the communication process both within and between cells. For people who are sensitive to certain foods, following a low-allergen diet may be beneficial to cellular health. 

Eat organically grown foods when you can! Eating organically grown foods can help protect cellular membranes since certain agricultural chemicals may damage the structure and function of the cellular membrane. The insecticide endosulfan and the herbicide paraquat have been shown to oxidize lipid molecules and therefore can damage the phospholipid components of the cellular membrane. In animal studies, pesticides such as chlorpyrifos, endrin and fenthion have been shown to over stimulate enzymes involved in chemical signaling, causing an imbalance that has been linked to conditions in which inflammation is a significant contributing factor, such as atherosclerosis and psoriasis. Eating organically grown foods also minimizes the degradation of DNA and may help to better sustain health. Recent test tube and animal research suggests that certain agricultural chemicals used in the conventional method of growing food may have the ability to cause genetic mutations that can lead to the development of cancer. One example is the chemical pentachlorophenol (PCP), which has been found to be able to cause DNA fragmentation in animals. Several of these agricultural chemicals used in the conventional growing of foods have also been shown to have a negative effect upon mitochondrial function. These chemicals include paraquat, parathion, dinoseb and 2,4-D, all of which have been found to affect the mitochondria and cellular energy production in a variety of ways including increasing membrane permeability (which exposes the mitochondria to damaging free radicals), and inhibiting the protein that creates ATP. 

Eat additive-free foods. Some of the food additives that are legally allowed in food processing in the United States have been identified as potentially able to damage genetic material. These include benzoyl peroxide, sodium bisulfite, butylated hydrotoluene (BHT) and butylated hydroanisole (BHA).

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