You've probably heard of antioxidants. But what exactly are antioxidants and what is their function in our body? In this article we describe everything you need to know about antioxidants.
In the first part we answer the question “what are antioxidants”. You then read more about how free radicals work, after which they zoom in on foods that are rich in antioxidants. We also explain three common antioxidants. We conclude this article by describing whether it is beneficial to take antioxidant supplements.
What are antioxidants?
To get straight to the point: Antioxidants are molecules that fight free radicals in your body. Free radicals are compounds that can cause damage when the numbers in your body get too high. Free radicals can be linked to multiple diseases, including diabetes, heart disease and cancer.
The great thing is that your body has its own so-called “antioxidant defense” to keep free radicals in check. However, your body can sometimes use some extra antioxidants. Fortunately, antioxidants are also found in food; especially in fruits, vegetables and other plant foods. Several vitamins – such as vitamins E and C – are also effective antioxidants.
Also, some antioxidants are used by the food industry to extend the shelf life of foods. Certain types of antioxidants can therefore be classified as preservatives. Now that the question “what are antioxidants” has been answered, we describe the action of free radicals in the next paragraph.
What is the function of free radicals?
In the previous paragraph “what are antioxidants” we briefly discussed free radicals. However, let's take a closer look at how free radicals work. Free radicals are constantly being formed in your body. Without antioxidants, free radicals would cause serious damage within a short period of time and, in the worst cases, eventually lead to death.
However, free radicals also perform important functions that are essential for health. For example, your immune cells use free radicals to fight infection. As a result, your body must maintain a certain balance of free radicals and antioxidants.
When there are more free radicals than antioxidants in your body, it can lead to a condition called “oxidative stress.” Long-term oxidative stress can damage important molecules (such as your DNA) in your body. Sometimes it even leads to cell death. Damage to your DNA increases the risk of cancer and some scientists theorize that it plays a critical role in the aging process.
Several stress, environmental, and lifestyle factors are known to promote excessive formation of oxidative stress and free radicals. With this you can think of:
- 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
- Excessive intake of zinc, magnesium, iron or copper
- Too much or too little oxygen in your body
- Excessive intake of antioxidants, such as vitamin E and vitamin C
- Deficiency of antioxidants
Basically, your body needs to maintain a certain balance between free radicals and antioxidants. Disrupting this balance can result in oxidative stress. Long-term oxidative stress also leads to an increased risk of negative health outcomes, such as cardiovascular disease.
Which foods contain antioxidants?
Antioxidants are necessary for all living things to survive. Your body generates its own antioxidants, such as the cellular antioxidant called “glutathione”. Plants and animals, as well as all other life forms, have their own defenses against free radicals and oxidative damage.
Therefore, antioxidants are found in all foods of plant and animal origin. Adequate intake of antioxidants is important. Your life even depends on the intake of certain antioxidants – think vitamins C and E.
However, many other non-essential antioxidants are found in food. Although they are not necessarily necessary for your body, they play an important role in general health. The health benefits of a diet rich in plants are largely due to the variety of antioxidants contained in that diet. For example, berries, green tea, coffee and dark chocolate are known as good sources of antioxidants.
According to some studies, coffee is one of the largest sources of antioxidants in the Western diet. This is not really surprising, because this is mainly because the average person does not eat many foods that are rich in antioxidants. Fish and meat products also contain antioxidants, but to a lesser extent than fruits and vegetables.
As described earlier in this article, antioxidants can extend the shelf life of both natural and processed foods. For that reason, they are often used as food additives. Vitamin C as an antioxidant , for example, is often added to processed foods to act as a preservative.
What types of antioxidants are in food?
Antioxidants can be categorized as water soluble or fat soluble. Water-soluble antioxidants act in the fluid inside and outside the cells, while fat-soluble antioxidants act primarily in the cell membranes.
While answering the question “what are antioxidants” we already briefly considered certain vitamins that can be classified as antioxidants. Important antioxidants in food include:
Vitamin C: This water-soluble antioxidant is an essential nutrient. A vitamin C deficiency should be remedied as soon as possible.
Vitamin E: This fat-soluble antioxidant plays a critical role in protecting cell membranes from oxidative damage. A vitamin E deficiency should therefore be prevented at all times.
Flavonoids: This group of plant antioxidants has many beneficial health effects.
Many nutrients that can be termed an antioxidant also have other important functions in the human body.
Well-known examples are so-called “curcuminoids” in turmeric and so-called “oleocanthal” in extra virgin olive oil. These substances act as antioxidants, but also have a powerful anti-inflammatory effect.
Should You Take Antioxidant Supplements?
Antioxidant intake is essential for optimal health, but more isn't always better. Excessive intake of antioxidants can have toxic effects and may even promote rather than prevent oxidative stress and damage .
Some studies even show that high doses of antioxidants increase the risk of death. For this reason, most health professionals advise avoiding high-dose antioxidant supplements, although further studies are needed before definitive conclusions can be drawn.
Eating lots of antioxidant-rich foods is a better idea. Studies show that foods reduce oxidative damage to a greater extent than supplements. For example, one study compared the effects of drinking blood orange juice with drinking sugar water, both of which contain equal amounts of vitamin C. It turned out that the juice had significantly greater antioxidant power.
The best strategy for ensuring adequate antioxidant intake is to eat a diet rich in various fruits and vegetables. However, low-dose antioxidant supplements, such as some high-quality multivitamins , may be beneficial if you are deficient in certain nutrients or unable to follow a healthy diet.