Updated 14 February 2013

Free radicals and chronic disease

We need oxygen to stay alive and burn food for energy. Unfortunately some of the oxygen molecules are damaged during the metabolic processes.

Why are free radicals bad for you? The answer lies in the oxygen we inhale as part of the process of burning food for energy.

When one burns wood or coal to produce heat, toxins are released in the form of smoke. The same happens when your body "burns" food for energy. This process is called metabolism and the toxic molecules produced as a result are called free radicals.

They are extremely destructive and damage cells if you are exposed to high levels over a long period of time. They also weaken the immune system, making you vulnerable to diseases and infections.

They can cause damage to your skin, brain, lungs, digestive track, arteries and your DNA – the genetic code that controls cellular behaviour. The reason is that they are constantly attacking body proteins, carbohydrates, fats and DNA. Scientists have estimated that every cell in the body suffers 10 000 free radical “hits” each day.

Research proved that excess free radicals over a prolonged period of time could trigger chronic diseases such as cancer, stroke, heart disease, diabetes and arthritis.

The role of the environment
Free radicals are, however, not only produced within the body but also from substances in the environment, such as exhaust fumes, tobacco smoke, alcohol, compounds in the food we eat, pollutants in the water we drink, and compounds in some medicines, particularly antibiotics.

They enter our bodies primarily via the skin, the lungs and the digestive tract from what we eat. Food is one of the more important sources of free radicals.

For instance, a high-fat diet can increase free radical production considerably. Research has shown that the breakdown of fats in the body produces more free radicals than does the breakdown of carbohydrates and proteins.

Free radicals can accumulate in cell membranes, causing them to break and the cell content to leak, rendering them useless. If they damage cells’ DNA, they can become confused and start behaving abnormally, such as suddenly starting to grow uncontrollably. This happens in many types of cancer. If they attack your pancreas, they can cause diabetes, in blood and blood vessels they can cause cardiovascular diseases.

Brain cells are vulnerable
Brain cells are especially vulnerable to free radical attacks since the brain generates more free radicals per gram of tissue than any other organ. The reasons are that it receives a large percentage of the body’s available oxygen from the blood supply and is active day and night.

Recent studies have established a connection between free radical damage and brain diseases such as Parkinson’s and Alzheimer’s. Even clinical depression and hyperactivity disorder (ADHD) are linked to excessive free radicals.

Reduce free radical production
Unfortunately there’s no way you can avoid free radicals, but there’s a lot you can do to reduce the numbers produced in your body, and to ensure that the maximum number of those that are produced, are neutralised.

You can reduce your exposure to free radicals in various ways. Avoid high-fat, high-sugar, over-processed foods. Stop smoking. Reduce exposure to solvents, chemicals and synthetic products such as insecticides. Get some exercise, but don't overdo it. Drink distilled water. Try to reduce stress, which also increases free radical production.

And supplement your diet with antioxidants, such as the proanthocyanidin complex found in grape seed extract to boost your natural antioxidant system. Sufficient antioxidants, both made by the body and derived from the diet, can mean the difference between a healthy and a diseased body.


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