Free Radicals And Oxidative Stress – The Problems They Can Cause And Ways To Minimize The Risks

You may have heard this term before, but if you’re not sure what they are, then you’ve come to the right place to find out more – about what they are, why they can be harmful, and what you can do to minimize any risks.

So let’s get straight to it.

What Are Free Radicals?

According to a study from the National Institutes of Health, “A free radical can be defined as any molecular species capable of independent existence that contains an unpaired electron in an atomic orbital.”

If that is a little bit too technical, then this short video featuring Dr. Mark Whitacre explains it better:

(Although he states that the atom is the smallest possible particle matter that cannot be divided any further, there are, of course, subatomic particles that have been known about for decades now, although this fact does not alter the basic premise of what he is saying.)

So, a free radical is basically unstable and highly reactive, and because it has an unpaired electron, then in order to fill the gap, as it were, it will try to steal an electron from another atom.

Examples of free radicals include:

• hydroxyl radical
• nitric oxide radical
• superoxide

So Why Are Free Radicals Harmful?

When molecules of oxygen split into single atoms that have unpaired electrons, they become unstable free radicals, which means they try to bond with other molecules or atoms.

If this process continues to happen, oxidative stress occurs.

Oxidative stress represents an imbalance between the free radicals in your body, and your body’s ability to counteract those free radicals.

In other words, as long as there aren’t too many free radicals in your body, and your body is healthy enough to mount an appropriate response to them, you will be fine.

But if the free radicals overpower your body’s defences, then health issues can arise.

That is when oxidative stress becomes oxidative damage

What Harm Can Oxidative Stress Lead To?

Oxidative damage has been associated with the following:

• autoimmune / inflammatory disorders (e.g. cancer, rheumatoid arthritis)
• cardiovascular diseases (e.g. atherosclerosis, hypertension) because of clogged arteries
• cataracts, including other age-related vision problems
• central nervous system diseases (e.g. Alzheimer’s, other forms of dementia)
• diabetes
• neuro-degenerative diseases (e.g. Huntington’s disease, Parkinson’s)
• visible signs of aging (e.g. graying hair, hair loss, loss of skin elasticity, wrinkles)

Remember that rust is the result of the oxidation of some metals (e.g. iron) – so you already know it’s probably not a good thing.

What Causes Oxidative Stress?

The following are all potential sources of free radicals and are therefore risk factors for oxidative stress / damage:

• Alcohol
• Chronic stress
• Fried foods
• Industrial chemicals (some but not all)
• Infections (e.g. Chlamydia pneumoniae, H. pylori, hepatitis C, P. gingivalis)
• Iron overload
• Obesity
• Ozone
• Pesticides (some but not all)
• Pollution
• Prescription medications (some but not all)
• Radiation
• Rancid vegetable oils (e.g. canola, peanut, safflower, soybean)
• Sedentary lifestyle
• Sleep problems
• Sugars
• Tobacco smoke

And, finally, insufficient antioxidants is another potential cause of oxidative damage, which I’ll talk about in a moment.

So What Are Antioxidants?

As the name suggests, antioxidants are substances that are capable of counteracting the often damaging effects of oxidation.

Technically, they are a type of nutrient (e.g. minerals, vitamins) or enzyme (e.g. proteins within your body that assist in chemical reactions).

Antioxidants neutralize the action of free radicals, but by doing so, they themselves become oxidized.

This is why you need a constant supply of antioxidants, because there are almost always free radicals in your body that need dealing with.

When free radicals release or steal one of their electrons, the result is another free radical, which in turn creates another one, and so, causing a chain reaction.

Antioxidants can help counteract free radicals in one of two ways – they can either inhibit the start of the chain reaction process, or they can terminate a chain that is already proliferating.

Enzymes such as catalase, glutathione peroxidase, and superoxide dismutase are examples of the first type of antioxidant (i.e. they can slow down the rate of chain initiation), while beta-carotene and both vitamins C and E are examples of the second type (i.e. they can terminate an active chain reaction).

This is why not all antioxidants work in all situations.

Sources Of Antioxidants

Here are some of the antioxidant nutrients:

• Beta-carotene
• Manganese
• Selenium
• Vitamin C
• Vitamin E
• Zinc

Here are some of the main antioxidant enzymes:

• catalase (CAT)
• glutathione peroxidase (GPx)
• superoxide dismutase (SOD)

And lastly, there are a few other sources not covered by the above two categories:

• Coenzyme Q10 (CoQ10, or ubiquinone)
• Phytochemicals (which are compounds found in some plants)
• Uric acid (which is a product of DNA metabolism and is, of course, one component of urine)

There are plenty of dietary sources of antioxidants, and you’ll find them referenced in several articles on this site. Examples include, but are not limited to, berries, broccoli, carrots, cherries, cinnamon, citrus fruits, dark leafy greens, fish (e.g. wild-caught Alaskan salmon), garlic, green tea, nuts, olives, onions, prunes, tomatoes, and turmeric.

You can also purchase antioxidant supplements (e.g. resveratrol, which can be found, for example, in grapes), but these should be a last resort if, for whatever reason, you are unable to obtain what you need from your food.

Other Ways To Reduce Oxidative Stress

There are also other lifestyle changes you can make that will reduce your risk of oxidative damage, including:

• Be careful with using industrial chemicals (e.g. garden products and household cleaners)
• Choose organic foods where possible, as these often are exposed to fewer dangerous chemicals (e.g. glyphosate)
• Eat smaller meals
• Get enough high-quality sleep on a regular (preferably daily) basis
• Reduce, or eliminate, your alcohol intake
• Regular exercise
• Stop smoking
• Take steps to reduce your stress (e.g. meditation, yoga)
• Treat infections, especially chronic ones, quickly and appropriately

Caveats

1. Be aware that studies investigating the benefits of antioxidants show mixed results – some concluded that they help, while others contradicted (or, at least, could not confirm) those results.
2. It is possible to ingest too many antioxidants, so it is recommended that you do not exceed the official RDAs. As an example, a study conducted in 2013 found that high doses of beta-carotene or vitamin E significantly increased the risk of dying.

Conclusion

It would appear that it is impossible to completely eliminate free radicals from your body, and provided that you eat a healthy diet and abstain from risky behaviours, they do not pose a significant problem.

The damage comes when your antioxidant levels are insufficient to counter the constant production of new free radicals.

As usual, I stand by my top three recommendations (i.e. eat healthily, get enough sleep, and exercise regularly), as the basis for overall good mental and physical health.

And, as I’m sure I’ve said elsewhere, balance is everything!

Additional Resources

These are suggestions for those who wish to delve deeper into any of the above:

1. Dietary Supplement Fact Sheets
2. Guided Stress Relief Hypnosis Session
3. Resveratrol