The Truth About Antioxidants

Written by Jonah Udall; Select sections of article written by and article reviewed by Dr. Bojana Jankovic Weatherly.

Walk into any natural health store, and you’re bound to see products labeled with claims like “cellular protection antioxidants,” or “antioxidant-rich for optimal health.” Antioxidants are popularly lauded for anti-aging effects, cancer-fighting abilities, and all kinds of health benefits, but what are they, really? We’re going to dive into the research about what antioxidants are – and are not – and how to harness their natural power to support your health.

Antioxidants are compounds that quench highly reactive molecules known as free radicals. Free radicals can damage DNA and interfere with cellular function by stealing electrons in a process called ‘oxidation.’ Antioxidants are martyrs, sacrificing themselves to become oxidized in order to spare our cells. Free radicals, and the wider category of reactive species, are normal byproducts of energy production and other cellular processes. These include reactive oxygen species (ROS) as well as reactive nitrogen species (RNS). It has often been suggested that aging itself results from the cumulative effects of this ‘oxidative stress’ over a lifetime.¹ Oxidative stress is also driven up by toxic exposures, radiation, infections, and imbalances in energy production such as insulin resistance and liver diseases. Sounds like a bad thing, right?

But before you go binge on the latest superfood antioxidant, this is not the whole story. As it turns out, normal levels of oxidative stress are actually beneficial and even necessary for optimal health. Say what?

MYTH #1: All oxidative stress is bad

For example, the thyroid gland requires the pro-oxidant hydrogen peroxide to produce thyroid hormone, the master metabolic regulator in the body.² Furthermore, some of the oxidative stress in an infection is intentional – free radicals are vital to the immune system’s defense against viruses and bacteria.³ And while excess free radicals may damage cells, free radicals are also important signaling molecules that regulate healthy bodily functions.⁴

Like many things, it’s about balance – not too much, or too little. Indeed, most research has found no benefit, and sometimes even harm in long-term supplementation with many nutritional antioxidants.⁵ This may also have to do with the second myth about how antioxidants work.

MYTH #2: Antioxidants you consume scavenge free radicals in the body

The popular belief about dietary and supplemental antioxidants is that they are beneficial because they go around the body quenching free radicals. However, research strongly suggests this is not true.⁶ Nutritional antioxidants are inert, they float around the bloodstream and into body tissues just like other nutrients. In order to quench free radicals, an antioxidant molecule would have to get lucky and bump into one before it oxidizes some part of a cell. And this can only happen once – after an antioxidant has become oxidized to neutralize a free radical, it cannot be oxidized a second time. Given the speed at which free radicals are created and move inside a cell, it is nearly impossible that free-floating antioxidants have any benefit in this way.⁶

But don’t fret, we don’t need to rely on random chance to buffer the damaging effects of excess oxidative stress. The body is much smarter than that!

MYTH #3: The most powerful antioxidants are the ones we consume

While nutritional antioxidants are not enough on their own, some can be powerfully therapeutic in certain conditions.⁷ This is most likely because, rather than scavenging free radicals themselves, they are helping to support and stimulate the body’s innate antioxidant defense systems.⁶ Yes, the most powerful antioxidants are made by the body itself. Instead of passively waiting to bump into a free radical by chance, these body-made antioxidants use targeted enzymes to seek out and rapidly eliminate free radicals and ROS in the most vulnerable places. Complementary enzymes rapidly regenerate these martyred antioxidants so they can continue to combat oxidative stress repeatedly. Because these enzyme systems are tightly controlled, the body can tightly regulate oxidative stress on its own terms when they’re functioning optimally – allowing just enough where it’s needed to support health, and reducing the rest.

To make matters more complex, some nutritional antioxidants, including the rich purple anthocyanins in dark berries, may stimulate our innate antioxidant systems by acting instead as pro-oxidant stressors.^6,8 This concept is called ‘hormesis,’ the idea that low levels of stress strengthen cellular responses, much in the way that lifting weights makes your muscles stronger. Indeed, exercise itself is a powerful hormetic stressor, which can become overt and damaging oxidative stress when overexercising.⁹

So, where does this leave us? In summary, oxidative stress needs to be balanced, not eliminated, for optimal health, and nutritional antioxidants can’t do it alone. The most powerful antioxidants are enzyme systems in the body, which can be trained in part by low-level pro-oxidant stimuli including some so-called ‘antioxidants’ and healthy exercise. Fortunately, there are more ways to support a healthy antioxidant balance.

Supporting the body’s master antioxidant system

The master of our body-made cellular antioxidants is glutathione, which may play a vital role in health and disease.¹⁰ Dementia, cancer, liver diseases, diabetes, hypertension, infertility, cystic fibrosis, multiple sclerosis, systemic lupus erythematosus, HIV, and Parkinson’s disease, just to name a few, have all been associated with depleted glutathione.¹¹ Whether or not this relationship is causal, supporting the body’s glutathione system can be a helpful component of promoting optimal health. But not only is glutathione an important antioxidant, it is also crucial for detoxifying some of the most pervasive and insidious environmental toxins, including pesticides, mold, mercury, and air pollution.^12–15

How can we support this powerful glutathione antioxidant and detox system? It’s not just about the molecule glutathione, which has become a popular supplement in recent years, but more importantly about supporting the enzymes that are responsible for its rapid and regenerating effects.¹¹ This means three things: supporting glutathione synthesis, antioxidant activity, and detoxification function. Supporting these three facets of the glutathione system can allow the body to optimally regulate oxidative stress and detoxification. While specialized nutraceuticals can be powerful in the right context, you can do a lot to bolster glutathione with food alone. Speak with a functional medicine doctor about whether therapeutic doses of antioxidants may be indicated in your condition, such as N-acetyl cysteine which has been shown to support glutathione status and mitochondrial function.¹⁶ We’ll leave you here with a few of the most powerful foods you can incorporate into your routine today to help optimize glutathione naturally!

Glutathione superfoods (supporting all three functions):

• Purple and blue polyphenols:^17–19 red grapes, blackberries, chokeberries, black currants, cranberries, sour cherries, blueberries, raspberries, pomegranate, boysenberries
• Rooibos and honeybush infusions^20,21
• Green and white tea^22–24

Synthesis supports:

• Whey protein^25,26
• Magnesium-rich foods (or supplements):^27,28 Seeds (pumpkin, flax, chia, sesame, sunflower); Nuts (Brazil, cashews, almonds); Grains (brown rice, oats, buckwheat, amaranth, wheat germ, quinoa); Legumes (edamame, black beans, peanuts); Greens (seaweed, kale, basil); avocado
• Cacao^29,30

Antioxidant supports:

• Extra virgin olive oil³¹
• Salmon³²
• Vitamin C-rich foods (or supplements):^33,34 bell peppers, chili peppers, acerola cherries, rosehips, guava, cantaloupe, parsley, kale, kiwi, broccoli, cauliflower, brussels sprouts, lemons, oranges, strawberry

Detox supports:

• Cruciferous vegetables:^15,35,36 particularly brussels sprouts, broccoli sprouts, red cabbage
• Rosemary^37,38

References:

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