How antioxidants fight free radicals and disease
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.