Antioxidants for Health
You have probably heard the word antioxidant thrown around everywhere, but have you wondered what is an antioxidant and whether antioxidants have any benefit to you?
What are Antioxidants?
Antioxidants are molecules that fight free radicals in your body.
Free radicals are compounds that can cause harm if their levels become too high in your body. They’re linked to multiple illnesses, including diabetes, heart disease, and cancer. Your body has its own antioxidant defences to keep free radicals in check.
However, antioxidants are also found in food, especially in fruits, vegetables, and other plant-based, whole foods. Several vitamins, such as vitamins E and C, are effective antioxidants.
Antioxidant preservatives also play a crucial role in food production by increasing shelf life.
How Free Radicals Function
Free radicals are constantly being formed in your body.
Without antioxidants, free radicals would cause serious harm very quickly, eventually resulting in death. However, free radicals also serve important functions that are essential for health.
For example, your immune cells use free radicals to fight infections. As a result, your body needs to maintain a certain balance of free radicals and antioxidants.
When free radicals outnumber antioxidants, it can lead to a state called oxidative stress. Prolonged oxidative stress can damage your DNA and other important molecules in your body. Sometimes it even leads to cell death. Damage to your DNA increases your risk of cancer, and some scientists have theorized that it plays a pivotal role in the aging process.
Several lifestyle, stress, and environmental factors are known to promote excessive free radical formation and oxidative stress. And the usual suspects make the list:
Air pollution
Cigarette smoke
Alcohol intake
High blood sugar levels
High intake of polyunsaturated fatty acids
Radiation, including excessive sunbathing
Bacterial, fungal, or viral infections
What do Antioxidants do?
The antioxidants protect other molecules in the body from a chemical process called oxidation. I feel some more chemistry coming on. Oxidation is the loss of an electron from an atom or molecule, and it can produce unstable chemicals called free radicals. Free radicals can damage molecules in our cells if their levels become too high, such as to our DNA (our genetic material) and proteins which carry out our bodily processes. Some oxidation reactions are necessary in our body, such as respiration to provide our body with fuel. You may have heard of the term, ‘oxidative stress’, when there is an imbalance of free radicals and antioxidants in your body. Some free radicals are good and our immune system uses them to for protection, but excess free radicals have been linked to a variety of health issues, so we need to keep their numbers in balance.
Your body has its own antioxidant system to mop up many of these free radicals produced each day as reactions take place in your body. Antioxidants are also found in many of the foods we eat, particularly fruits, vegetables, nuts, seeds and wholegrains.
What Foods are High in Antioxidants?
Most of our plant foods are rich in antioxidants. There are many different antioxidants, most with big, hard to pronounce names and different foods have higher levels of different ones!
Antioxidants are often responsible for the beautiful, vibrant colours of fruits and vegetables, with darker ones generally having greater amounts. For example, the dark green and purple lettuce leaves versus light green or white leaves. To make sure you are eating a variety of antioxidants it is quite easy - choose a variety of different coloured plant foods, particularly fruits and vegetables, nuts and seeds. If you aim for the recommended two fruit and five vegetables and a handful of nuts per day you are on your way!
Here are just a few antioxidants and the foods they are found in3. See how many different fruits and vegetables you can eat everyday.
anthocyanins – eggplant, grapes and berries
beta-carotene – pumpkin, mangoes, apricots, carrots, spinach and parsley
copper – seafood, lean meat, milk and nuts
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
lutein – green, leafy vegetables like spinach, and corn
lycopene – tomatoes, pink grapefruit and watermelon
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.
Types of Dietary Antioxidants
Antioxidants can be categorized as either water- or fat-soluble. Water-soluble antioxidants perform their actions in the fluid inside and outside cells, whereas fat-soluble ones act primarily in cell membranes.
Important dietary antioxidants include:
Vitamin C - This water-soluble antioxidant is an essential dietary nutrient.
Vitamin E - This fat-soluble antioxidant plays a critical role in protecting cell membranes against oxidative damage.
Flavonoids - This group of plant antioxidants has many beneficial health effects.
Many substances that happen to be antioxidants also have other important functions. Notable examples include curcuminoids in turmeric and oleocanthal in extra virgin olive oil. These substances function as antioxidants but also have potent anti-inflammatory activity.
Should you get Antioxidants from Food or Take Supplements?
It’s best to get your antioxidants from a well-rounded and nourishing diet rather than from supplements. But in saying that, unfortunately, only 5% of us eat the recommended daily amount of fruit and veg. If you have an antioxidant deficiency due to lifestyle, supplementation may be of benefit.