What are antioxidants?
In plain and simple English, "antioxidants are the disease-fighting compounds that Mother Nature puts in foods to help our bodies stay healthy" - explains researcher Jeffrey Blumberg, PhD.
Antioxidants are a group of molecules valued for its capability of inhibiting the oxidation of another molecule. Antioxidants can be man-made or natural. Some well-researched antioxidants include antioxidant vitamins C and E, carotenoids, such as beta-carotene and zeaxanthin, and micro-elements like selenium.
Benefits of antioxidantsTo understand what's so valuable about the way antioxidants work, we need to understand the what are free radicals. In 1990s, scientists began to understand that free radical damage played a role in the early stages of atherosclerosis and possibly contributed to conditions such to cancer, vision loss, and a host of other chronic diseases.
What are free radicalsFree radicals are atoms or molecules containing unpaired electrons, which makes them highly reactive with other cellular structures. They are natural by-products of ordinary metabolic processes and immune system responses in the body. Free radical-generating substances can be found anywhere: in our food, medicines, the air and even in the water we drink.
Free radicals may cause damage to proteins, DNA, and cell membranes by robbing them of electrons through a process called oxidation. This “oxidative damage” of important components of the cell can impact their ability to function normally, eventually causing the cell to die. Multiple studies show that overproduction of free radicals contributes to nerve cell injury and diseases.
What are the different types of antioxidants?There are several ways to categorise antioxidants.
They can be classified according to their solubility - they are soluble in lipids/fat (hydrophobic) or water (hydrophilic).
Additionally, there are enzymatic and non-enzymatic antioxidants. The main enzymatic antioxidants are superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHpx) and glutathione reductase. Non-enzymatic antioxidants include carotenoids, vitamin C, vitamin E, plant polyphenols, and glutathione (GSH).
What antioxidants to include in your nutrition?For optimal benefit, you'll want to supply your body with a wide range of antioxidants.
Some of these important substances are already produced in your organism.
Alpha-Lipoic Acid (ALA) is an antioxidant present in every cell of the body, playing a role in turning glucose into energy. Unlike other antioxidants, alpha-lipoic acid is both fat and water soluble, which allows it to work throughout the body. When antioxidants attack free radicals in our body, their resources deplete. Evidence indicated that alpha-lipoic acid may support regeneration of these other antioxidants, helping reactivate them again.
Several studies indicate that Alpha-Lipoic Acid helps decrease blood sugar levels and improve insulin sensitivity.
Since alpha-lipoic acid can pass easily into the brain, it may support protection of the brain and nerve tissue, and it's currently being investigated as a potential treatment for stroke and dementia.
CoQ10 (Ubiquinone) is a powerful antioxidant, found in almost every cell in the body.
Some studies suggest that coenzyme Q10 supplements may help prevent or treat the following conditions:
- Heart care after a heart attack
- Heart failure (HF)
- High blood pressure
Preliminary studies found that CoQ10 improves blood sugar control. CoQ10 supplements may boost heart health and stabilise blood sugar, thus supporting high blood pressure management in people with diabetes.
Preliminary clinical studies suggest that CoQ10 may better immune function in people with HIV or AIDS, have a positive effect on male fertility, have a role in the treatment of Parkinson disease and help prevent migraines. Further studies are needed to precisely determine the safety and effectiveness of these treatments.
Dietary sources of CoQ10 include oily fish, organ meats, and whole grains.
Glutathione (GSH) is a naturally occurring chemical used by the human body to shield against environmental and chemical threats. Over 81,000 of scientific papers have confirmed glutathione (GSH) as one of the most crucial protective molecules in the body.
The level of GSH in the body can decrease as a result of ageing, diet, lifestyle and disease. Decreased GSH levels have been associated with diseases such as cardiovascular disease and diabetes.
There is a group of antioxidants which cannot be produced by human organism. Including them in your diet through consuming antioxidant-rich foods or supplements is especially important.
Resveratrol has been demonstrated to possess various biological activities, which could play a role the treatment as well as prevention of cancer, cardiovascular disease, and neurodegenerative diseases (preclinical studies). (http://lpi.oregonstate.edu/mic/dietary-factors/phytochemicals/resveratrol#food-sources)
Resveratrol is naturally found in grapes, peanuts, red wine, and some berries.
Carotenoids are valued for their positive impact on the ageing process and various diseases, because of their antioxidant properties. Carotenoids have been found to display "beneficial mechanisms of action" for a range of conditions, including cancers, age-related macular degeneration, cardiovascular disease and cataract formation.
Astaxanthin is a particular type of carotenoid, boasting a wide range of impressive health benefits. Multiple studies support the use of astaxanthin as a powerful antioxidant which may be beneficial in reducing the risks of certain chronic diseases. It may contribute to reducing oxidative stress in the nervous system, decreasing the risk of neurodegenerative diseases. In addition, astaxanthin boasts well-documented immune-stimulating and anti-inflammatory properties.
Preliminary research indicates that astaxanthin may help reduce wrinkles and fine lines and improve skin moisture content and elasticity. Further research is underway.
Astaxanthin naturally occurs in nature primarily in sea organisms such as microalgae, salmon, trout, krill, shrimp, crayfish, and crustaceans. Chlorella is considered a good plant-based source of astaxanthin.
Vitamin C is a water-soluble vitamin, also known as ascorbic acid. Most mammals and other animals can produce vitamin C, but humans have to obtain it through proper nutrition.
Ascorbic acid is a potent antioxidant vitamin. Every day, free radicals and reactive oxygen species damage indispensable molecules in the body. These processes take place during normal metabolism and through exposure to toxins and pollutants. Even small amounts of vitamin C can protect indispensable molecules such as proteins, carbohydrates, lipids and nucleic acids (DNA and RNA). Additionally, vitamin C also participates in redox recycling of other powerful antioxidants; for example, it is known to regenerate vitamin E from its oxidised form.
Vitamin E is, in fact, the collective name for a group of fat-soluble compounds with unique antioxidant activities. Out of eight of chemical forms, Alpha- (or α-) tocopherol is the only form that meets human requirements.
Vitamin E is a fat-soluble antioxidant which stops reactive oxygen species, formed when fat undergoes oxidation.
Limited clinical evidence implies that vitamin E supplementation might be beneficial for managing age-related macular degeneration.
Although severe vitamin E deficiency is rare, marginal deficiency of vitamin E is relatively common. It's been estimated that 93% of American adults do not meet the estimated average dietary requirement from food. http://lpi.oregonstate.edu/mic/vitamins/vitamin-E
Boosting your intake naturally can be achieved by consuming more nuts, seeds, and vegetable oils , which are among the best sources of alpha-tocopherol. Notable amounts can also be found in green leafy vegetables.
What are the top high antioxidant foods?
Antioxidant compounds: beta-carotene, vitamin A, vitamin C, vitamin E, zeaxanthin
Goji berries are considered to contain the richest and most complete spectrum of antioxidant carotenoids of all known foods.
Goji berries contain a multitude of nutrients and bioactive compounds which earn them a title of "superfruits". They've been utilised in traditional Chinese medicine for hundreds of years, valued as an important element of a health-promoting diet.
Antioxidant compounds: anthocyanin
In one study on cellular antioxidant activity of 25 common fruits, wild blueberry emerged as a champion in demonstrating antioxidant activity. It demonstrated the highest phenolic content and the highest cellular antioxidant activity. (Wolfe K.L., Kang X., He X., Dong M., Zhang Q., Liu R.H. Cellular Antioxidant Activity of Common Fruits.
Journal of Agricultural and Food Chemistry (2008). 56 (18): 8418–8426)
Do not confuse them with ordinary blueberries - the antioxidant power of wild blueberries is two times higher.
Antioxidant compounds: anthocyanin, flavonoids, epicatechin, catechin
Studies found that dark chocolate improves vascular function, increases insulin sensitivity and boosts overall cardiovascular health.
Studied benefits of dark chocolate (cocoa bean) include:
- Improving skin condition and protecting against UV damage.
- Improving exercise endurance.
- Might help extend lifespan.
- Anti-inflammatory properties.
Antioxidant compounds: vitamin E
In a review of over 100 foods, carried out by the USDA Arkansas Children’s Nutrition Center, pecans ranked highest in antioxidant capacity among all nuts.
Thanks to its vitamin E content, pecans might may play a role in protecting the nervous system.
Research from Loma Linda University demonstrated that boosting your diet with a handful of pecans each day could help inhibit unwanted oxidation of blood lipids, protecting against coronary heart disease.
Antioxidant compounds: vitamin C
The benefits of this undervalued vegetable are astounding. Research has demonstrated the artichokes' ability to strengthen the immune system, lower cholesterol and detoxify the liver. Also, it might also protect against diabetes, heart attacks, strokes and even cancer. These fibre rich plants can help settle digestive issues, decrease blood pressure and even banish hangovers.
Antioxidant compounds: anthocyanins and phenolic compounds
These purple-black fruits are one of the richest sources of phenolic compounds and anthocyanins among small fruits and have been found to have a strong antioxidant capacity. Not surprisingly, elderberries have been used medicinally by various indigenous cultures for centuries. Included as a part of a balanced diet, elderberries exhibit an impressive range of antioxidant protection and therapeutic benefits such as reduced risk of coronary heart disease, anticarcinogenic activity, reduced risk of stroke, improved visual acuity and cognitive behaviour.
Antioxidant compounds: enzyme superoxide dismutase
Antioxidant-rich foods aren't necessarily exotic or expensive. Common kidney beans are a high-octane source of antioxidants.
Antioxidant compounds: Anthocyanins, Ellagic acid, Quercetin, Resveratrol, Selenium, Vitamins A, C and E
A growing body of research indicates that polyphenols, including those found in cranberries, may contribute to reducing the risk of cardiovascular disease and have anti-inflammatory properties.
Natural antioxidant production in your body might decline as you age. Those who choose to increase their daily intake of antioxidants should be careful to not consume too much. Supplementing with high doses of beta-carotene can reportedly the risk of lung cancer in smokers. Additionally, supplementing with high doses of antioxidant vitamin E may increase risks of a particular type of stroke and prostate cancer.