Recently, one of the most talked-about topics in healthy living circles and beyond is none other than antioxidants. They have scooped away all the attention because of many claims of their health benefits. Let’s learn something new today and take a look at them more closely.
WHAT ARE ANTIOXIDANTS?
Most simply put, they are substances that may protect our cells from oxidative damage (oxidative stress) caused by unstable molecules called free radicals. This damage can lead to inflammation, heart disease, cancer, and other diseases.
Free radicals are produced as inevitable byproducts when our body breaks down food and turns it into energy, but also much more when we are exposed to tobacco smoke, air pollution, and UV radiation.
They can play important roles in many normal cellular processes, but when their levels are high, free radicals can be hazardous to the body and damage all major components of cells.
Free radical damage can:
- make changes in DNA
- make bad cholesterol (LDL) molecule more likely to get trapped in an artery wall
- alter cell’s membrane, changing the flow of what enters and what leaves the cell
Antioxidants are the preventers and fighters against the effects of free radicals and there is a wide variety of substances with antioxidant activity.
The presence of antioxidants in food may prevent oxidation and may serve as a natural defense.
HOW CAN THEY HELP?
Many studies were conducted regarding the effects of antioxidants on the prevention and reduction of damage caused by free radicals. And the results are mixed.
Current research in cancer shows two different aspects of antioxidants.
The dark side is that it may not help at all with the treatment of cancer, as shown in a few studies. But on the bright side, research showed that antioxidants can protect against oxidative damage influenced by cigarette smoking thereby reducing the risk of cancer.
More research is needed, but this may suggest that when antioxidants are taken by healthy individuals they have beneficial effects, but when tumors are forming or formed, high doses of antioxidants should be prevented just in case, until more research is done.
- Hearth health
Many studies were conducted and indicated that antioxidants may prevent atherosclerosis. Oxidation of bad cholesterol (LDL) is one of the major steps in the becoming of atherosclerosis and it was shown that antioxidants can help prevent it.
Oxidative stress has a big role in the pathogenesis of complications associated with diabetes. Antioxidants have been found to defend against the oxidative burst associated with diabetes and in turn help in reducing the hyperglycaemic state in diabetes.
- Brain health
Oxidative stress has been linked to several central nervous system disorders.
Proteins that act as antioxidants (thioredoxins) and play a role in the regulation of redox signaling ( transduction of signals coding for cellular processes) have been associated with protective effects in nerve cells.
- Oral health
One of the most common chronic conditions that affect people worldwide are periodontal diseases. The leukocytes respond to chronic inflammation by releasing reactive species responsible for the oxidative damage to the gingival and the periodontal tissues.
The biological substances with potent antioxidant capacity that have been studied in periodontal disease include Vitamin C, vitamin E, carotenoids, polyphenols, bilirubin, and more.
It has been observed that certain components present in green tea such as epigallocatechin-3-gallate have been found to reduce the risk of development of dental caries and plaque formation by its scavenging effect.
One probable reason why many studies on antioxidant supplements do not show a health benefit is that antioxidants tend to work best in combination with other nutrients, plant chemicals, and even other antioxidants.
A vitamin C supplement does not contain the plant chemicals (polyphenols) naturally found in strawberries like proanthocyanins and flavonoids, which also possess antioxidant activity. They can mix up with vitamin C and help fight many diseases.
There is a question if a nutrient with antioxidant activity can cause the opposite effect with pro-oxidant activity if too much is taken. This is why using an antioxidant supplement with a single isolated substance may not be the best possible strategy for all of us.
Differences in the amount and type of antioxidants in foods versus those in supplements might also influence their effects.
For instance, there are eight chemical forms of vitamin E present in foods, but vitamin E supplements typically only include one form, alpha-tocopherol.
WHERE TO FIND THEM?
A higher intake of fruits, veggies, and legumes plentiful in antioxidants is associated with a lower risk of oxidative damage and diseases like cancer, cardiovascular disease, etc.
Some of the substances having the power of antioxidant activity are:
- Vitamin C – found in broccoli, red and green peppers, orange juice and oranges, brussel sprouts, grapefruit and grapefruit juice, kale, strawberries, kiwi, cauliflower, cabbage, and cantaloupe
- Vitamin E – found in sunflower seeds, almonds, hazelnuts, wheat germ oil, peanuts, and peanut butter, spinach, broccoli, tomatoes, and mangoes
- Carotenoids (β-carotene, lycopene) – in apricots, asparagus, beet, broccoli, cantaloupe, carrots, kale, peaches, pumpkin, sweet potato, and mangos
- Zinc- in baked beans, sesame seeds, pumpkin seeds, chickpeas, lentils, cashews, fortified cereals
- Phenolic compounds:
Quercetin – found in apples, berries, grapes, red wine, onions
Catechins – in tea, cocoa, strawberries, blackberries, black grapes, cherries
Resveratrol – sources are grapes, peanuts, pistachios, berries, cranberries
Coumaric acid – found in spices, berries, basil, garlic
Anthocyanins – in blueberries, blackberries, strawberries, cranberries, cherries
Plant-based foods are the best sources of antioxidants, and also high in fiber, low in saturated fats, good sources of vitamins and minerals, which only heightens the beneficial effects.
So far, research showed that some trials have had limitations. However, there is an abundance of evidence suggesting that eating fruits, vegetables, and whole grains rich in nutrients provides protection against many problems and conditions. One way or another, you can’t be wrong with eating proper amounts of fresh fruits and veggies, but you can always consult your doctor just to be sure.
- Mayo Clinic, “Antioxidants”, org
- Harvard School of Public Health, “Antioxidants”, Harvard.edu
- Sarangarajan, S. Meera, R. Rukkumani, P. Sankar, G. Anuradha, “ Antioxidants: Friend or foe?”, Asian Pacific Journal of Tropical Medicine, Volume 10, Issue 12, 2017, ScienceDirect