Antioxidants: Fight Free Radicals for a Longer, Healthier Life


Antioxidants in berries

When it comes to anti-aging and disease-proofing your life, fighting free-radicals (aka – oxidation) is an important job.

But what might surprise you is that you get more free-radical protection from the antioxidants manufactured INSIDE your body than you do from your food.

It’s true!

Endogenous antioxidants (meaning “antioxidants produced or synthesized within the organism”) are free-radical fighters made primarily by the liver. They include the phase 2 detoxifying enzymes (glutathione and quinone reductase) as well as superoxide dismutase.

In this article you’ll learn about the specific foods you need to eat to help your body create these powerful endogenous antioxidants.

But before we show you the foods that can flip your internal antioxidant switch to the “on” position, let’s talk about what antioxidants really are.

Free Radicals & Antioxidants

Antioxidants are compounds that protect cells from damage from free radicals.

While the most common cause of free radical generation is simply breathing in and out, exposure to various environmental factors, including tobacco smoke and radiation are also big (preventable) factors of oxidation in the body.

Of course, the Standard American Diet is also a key generator of free radicals thanks to:

  • Sugar: Whether it comes from a can of soda or dried fruit, eating sugar raises blood sugar levels and causes advanced glycation endproduct(AGEs) to form. AGEs cause oxidation, as well as cellular damage and inflammation.
  • Oxidized fats: Eating oxidized fats – either from using oils above their flash point – or consuming low quality omega-6 rich vegetable oils promotes oxidation.
  • Damaged proteins: Cooking meats at high temperatures creates heterocyclic amines – carcinogenic substances that induce oxidative damage to DNA.
  • Damaged carbohydrates: Carbohydrates cooked at high temperatures (think cereals, chips and crackers) contain acrylamide – a cancer-causing substance that causes oxidative stress .

So whether you’re drinking soda, eating donuts and french fries or even so-called “healthy” crackers and vegetable oils a lot of oxidative damage can be done through diet.

And oxidative stress contributes to chronic disease.

How? When an oxygen molecule (O2) becomes electrically charged or “radicalized” it tries to steal electrons from other molecules, causing damage to DNA and other molecules. Over time, this damage ravages tissues, vessels and cells leading to a range of chronic diseases including heart disease, Alzheimer’s disease, macular degeneration and cancer, to name a few.

But antioxidants interact with and stabilize free radicals, helping to buffer that damage.

Key Antioxidant Nutrients

Let’s take a closer look at some of the phytonutrients (found in plant foods) and zoonutrients (from animal sources) that help to protect against oxidation.

  • Ajoene: This sulfur-rich nutrient, found exclusively in garlic, helps to inhibit the release of superoxide—the most common free radical in the human body.
  • Allicin: Also found in garlic, allicin helps induce the body’s phase 2 detoxifying enzymes.
  • Anthocyanins: This group of more than 400 red-blue substances is found primarily in berries and scavenges four types of cell-damagers—superoxide radicals, hydrogen peroxide, hydroxyl radicals and singlet oxygen.
  • Astaxanthin: Found in wild salmon, shellfish and microalgae, astaxanthin shows antioxidant capacity 10 times stronger than other carotenoids. It’s also a natural internal sunscreen that protects skin from sun damage and discoloration.
  • Carotenoids: This diverse group of more than 600 lipid-soluble plant pigments includes beta-carotene, alpha-carotene, lycopene, lutein, astaxanthin, zeaxanthin and cryptoxanthin. Because of their lipid-soluble nature, carotenoids are believed to be most protective in cell membranes.
  • Curcumin: Found exclusively in turmeric, not only does this potent antioxidant scavenge free radicals, it also kicks up the body’s phase 2 detoxifying enzymes.
  • EGCG: Found in green tea, this potent antioxidant scavenges free radicals, fights inflammation and boosts the body’s phase 2 detoxifying enzymes.
  • Ellagic Acid: A potent antioxidant found in raspberries, strawberries, cranberries, walnuts, pecans and pomegranates that neutralizes free radicals and disarms carcinogens.
  • Ergothionene: This antioxidant is found in mushrooms (shiitake, oyster, king oyster and maitake have the most). While ergothionene does not contribute to total antioxidant activity in the mushroom, it may significantly boost antioxidant activity in the body.
  • Flavonoids: This large family of phytonutrients is found in a wide variety of healing foods—including apples, onions, tea, red wine, berries, citrus, cocoa and beans. Researchers believe that flavonoids protect cells by increasing the body’s production of phase 2 detoxifying enzymes and help to reduce inflammation, rather than acting as direct antioxidants.
  • Glucosinolates: Found in cruciferous vegetables, glucosinolates are one of the most sulfur-rich groups of nutrients, helping to induce the phase 2 detoxifying enzymes and reduce inflammation. While fresh cruciferous veggies all start out with glucosinolates, they turn into isothiocyanates—including sulforaphane, phenethyl-isothiocyanate (PEITC) and others—when chewed and digested.
  • Resveratrol: Primarily found in red wine, resveratrol has potent antioxidant activity, protects DNA from damage and has been found to boost longevity too.

Learn more about how you can boost glutathione  – your body’s master antioxidant and detoxifier and learn about the high ORAC foods you should be enjoying everyday for maximum free radical protection.

Antioxidants - Found in:

Acai, açaí, Artichokes, Blueberries, Beans, Cocoa, Blackberries, Spices, Strawberries, Raspberries, Cloves, Cinnamon, Pecans, Apples, Red Wine, Kidney Beans, Black Beans,
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About The Author

Kelley Herring, founder of Healing Gourmet, is a natural nutrition enthusiast with a background in biochemistry. Her passion is educating on how foods promote health and protect against disease and creating simple and delicious recipes for vibrant health and enjoyment.

Kelley Herring – who has written posts on Healing Gourmet.

About Kelley Herring

Kelley Herring, founder of Healing Gourmet, is a natural nutrition enthusiast with a background in biochemistry. Her passion is educating on how foods promote health and protect against disease and creating simple and delicious recipes for vibrant health and enjoyment.

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