Antioxidants: What you should know...

Free radicals

To understand why you need antioxidants, first you must understand free radicals…

Free radicals are types of molecules that contain unpaired electrons. These unpaired electrons make them highly reactive and unstable. In science, they can be termed as oxidants or reductants. Hydrogen peroxide, superoxide anion radicals and hydroxyl radicals are a few examples of free radicals.

Within the body, these highly reactive free radicals are capable of damaging your DNA, proteins, carbohydrates and lipids. They do this by attacking important molecules, which leads to cell damage and homeostatic disruption.

Homeostasis refers to the maintenance of a stable environment within your body, for example normal heart rhythm, blood pressure and body temperature.

In summary, free radicals can damage your body and this damage can be significant and may result in disease or illness.

Where do free radicals come from?

They are made in the body…

Free radicals are derived from normal metabolic processes that occur frequently in the body.

For example, free radicals are continuously formed within our cells as a result of a number of essential chemical reactions; such reactions include those involved in respiration, phagocytosis (part of the immune function) and prostaglandin synthesis (involved in inflammation).

Further to this, free radicals are also produced as a result of exercise (yes, exercise), as well as via the detoxification of drugs (cytochrome P450 system).

They come from external sources…

Free radicals can also come from a number of sources outside the body, including exposure to x-rays, ozone, air pollution, cigarette smoking, industrial chemicals, certain drugs and pesticides.

Atherosclerosis, cancers & free radicals

Atherosclerosis (plaque build up in the arteries) and cancer, both major causes of death, are prominent ‘free radical’ diseases.

It is possible that free radical reactions may result in tumor (cancer) formation.

In relation to atherosclerosis, a number of studies have revealed that this disease may also be a result of free radical reactions that involve diet derived fats and oils inducing endothelial (lining of blood vessel) cell injury. This then produces changes in the arterial walls, i.e. damaged arteries.

Oxidative stress

When there are more free radicals than antioxidants, oxidative stress (damage) can occur to a wide range of moleules within the body, including proteins, lipids and DNA.

Examples of short-term oxidative stress include:

  • Excessive exercise

  • Trauma

  • Infection

  • Toxins

  • Heat injury

Longer term oxidative stress...

Oxidative stress is now thought to make a significant contribution to:

  • All inflammatory diseases (e.g. arthritis)

  • Ischemic diseases (e.g. heart disease, stroke)

  • Hemochromatosis

  • Emphysema

  • Gastric ulcers

  • Hypertension (high blood pressure)

  • Neurological disorders (e.g. Alzheimer’s disease, Parkinson’s disease)

  • Alcoholism

Antioxidants – What are they?

An antioxidant is a molecule that can donate a spare electron to a rampaging free radical, which in turn neutralizes it and prevents it causing damage.

Antioxidants are manufactured in the body…

Glutathione, ubiquinol and uric acid are some types of antioxidants that are produced during normal metabolism in the body.

Antioxidants that must come from the diet…

The principal antioxidants that come from the diet are specific types of vitamins, including:

  • Vitamin E (alpha-tocopherol)

  • Vitamin C (ascorbic acid)

  • Beta-carotene

For a list of antioxidant rich foods, click here.

Synthetic antioxidants…

These have been found to be dangerous to human health.

In summary

  • Free radicals contribute to both short and long term damage across the body.

  • Free radicals likely have a strong influence on chronic health problems, including cancer, cardiovascular disease and inflammatory conditions.

  • Free radicals speed up the ageing process.

  • Antioxidants prevent free radical damage via stopping the formation of radicals, scavenging them up, or by encouraging their decomposition.

  • A diet rich in antioxidants is highly encouraged for better health.

  • In general, eat more plants.