What are free radicals?

Free radicals are created naturally by performing biological processes such as digesting the food we eat, breathing, metabolising alcohol and drugs, and converting fats into energy.

Free radicals aren’t all bad! When a low or moderate level of free radicals is balanced, multiple beneficial roles occur. This includes our bodies ability to fight pathogens and infection.

Oxidative stress occurs when there is an imbalance of excessive amounts of free radicals within the bodies cells and tissues which outweigh our biological ability to detoxify them.

Where do free radicals come from and what causes disease?

Free radicals are produced from both external and internal causes.

Exogenous (external) sources include:

• Certain pharmacologically prescribed drugs

• Environmental pollution

• Asbestos

• Radiation

• Heavy metals

• Alcohol

• Smoking

• Cooking methods such as what oil being used, charring or smoking meat

• Cleaning products

• Excessive exposure to sunlight

Endogenous (internal) sources include:

• Infection

• Inflammation

• Excessive exercise

• Mental stress

• Ageing

 There is a strong link between oxidative stress and the progression of many diseases such as:

• Cardiovascular disease

• Neurological, renal and liver disorders

• Inflammation

• Degenerative disorders associated with ageing such as parkinsons and huntingtons disease

• Diabetes

• Obesity

• Preeclampsia

• Infertility

• Gastric ulcers

• Cancer of the prostate, breast, lung, bladder and colorectal to name a few.

Ageing results from a build up of cell and molecular damage and reduces cellular regeneration.

Antioxidants and free radicals

The role of antioxidants in foods is to stop or delay the progression of cellular damage and disease. The best source of antioxidants is by gaining them through food. Alternatively antioxidants can be accessed via supplements and functional foods however eating a wide variety of plant foods particularly, vegetables, fruit, nuts, seeds, extra virgin olive oil, whole grains and tea is the best way to get a wide variety.

In summary, free radicals are not all bad! They are a naturally occurring bi-product of the body’s metabolic processes used to function. However free radicals in excessive amounts cause oxidative stress, which leads to illness and disease. This is combated by antioxidants which can be produced within the body and sourced from a well balanced diet.

Good sources of antioxidants:

allium sulphur compounds – leeks, onions and garlic

• anthocyanins – eggplant, grapes and berries

• beta-carotene – pumpkin, mangoes, apricots, carrots, spinach and parsley

• catechins – red wine and tea

• copper – seafood, lean meat, milk and nuts

• cryptoxanthins – red capsicum, pumpkin and mangoes

• flavonoids – tea, green tea, citrus fruits, red wine, onion and apples

• indoles – cruciferous vegetables such as broccoli, cabbage and cauliflower

• isoflavonoids – soybeans, tofu, lentils, peas and milk

• lignans – sesame seeds, bran, whole grains and vegetables

• lutein – green, leafy vegetables like spinach, and corn

• lycopene – tomatoes, pink grapefruit and watermelon

• manganese – seafood, lean meat, milk and nuts

• polyphenols – thyme and oregano

• selenium – seafood, offal, lean meat and whole grains

• vitamin A – liver, sweet potatoes, carrots, milk, and egg yolks

• vitamin C – oranges, blackcurrants, kiwifruit, mangoes, broccoli, spinach, capsicum and strawberries

• vitamin E – vegetable oils (such as wheatgerm oil), avocados, nuts, seeds and whole grains

• zinc – seafood, lean meat, milk and nuts

• zoochemicals – red meat, offal and fish. Also derived from the plants that animals eat.

Source Better Health Channel.