We often hear words like antioxidant, oxidative stress, free radicals and reactive oxygen species thrown around all the time in skincare, diet and supplements in shampoo. One of the key causes to body aging is oxidative stress, which is caused by free radical damage.
Free radicals are substances – molecules or atoms – with an unpaired electron. Electrons like to be paired up, so free radicals are really reactive because they try to get an extra electron to be stable. They’re so unstable that they’ll take an electron from anything that’s around. When a free radical takes an electron, the substance that loses the electron to the free radical will become oxidized, that’s why it’s called oxidative stress. Losing an electron will also make the substance reactive and thirst for electron from other substances, and then the cycle continues into a chain reaction.
A lot of the free radicals in living organisms contain oxygen, so they’re often called reactive oxygen species or ROS. The most common free radicals in humans are superoxide and hydroxyl. The process of stealing electron involves breaking and forming of chemical bonds which can lead to irreversible changes in the substance’s structure and function.
Free radicals are useful in many occasions, like free radical polymerization which is used to make most of the plastics that we use today. They’re also important in lots of biological processes. Free radicals are also the reason that benzoyl peroxide acne cream works to kill acne bacteria.
But if free radicals form in the wrong place at the wrong time, then they’ll react with important substances like DNA proteins, lipids around the skin and these chain reactions will cause a lot of microscopic damage that’s eventually reflected as wrinkles, fine lines, thinning skin, pigmentation and even cancer.
Free radicals can also trigger inflammation and other pathways in your skin that lead to damage like increasing the amount of matrix metalloproteinases (MMPs) which are enzymes that break down collagen in your skin. Collagen works to make your skin plump and bouncy.
Free radicals are formed during normal biological processes like respiration where oxygen is used to break down food to give our bodies energy. These are unavoidable processes but environmental factors like UV light from the sun, pollution and smoking can cause more free radicals to form in your body and then will affect your skin. In your skin UV is particularly bad. Free radicals form in your skin within 15 minutes of UV exposure and they’ll keep on being produced for up to an hour afterwards. Both UVA and UVB can cause free radical formation. UVA penetrates deeper into your skin so it can cause deeper damage.
Avoid bad environmental factors by not smoking and reducing pollution in our cities. Stay in the shade or apply sunscreen to avoid UV. But it is also possible to prevent free radical damage after they’ve been formed, and the best way is through antioxidants.
An antioxidant is a substance that can neutralize free radicals. They’re usually substances that are pretty stable with an unpaired electron. Once the free radical takes their electron, the chain reaction will stop.
Essentially, antioxidants are like shields or sponges that intercept the free radicals before they have a chance to react with more important biological molecules. Your body naturally contains antioxidants that can soak up these free radicals.
Antioxidant enzymes like superoxide dismutase, catalase and glutathione peroxidase are the most common ones. There are also smaller antioxidants like vitamin C and E, coenzyme q- which is also known as ubiquinol and glutathione. However, these natural antioxidant systems in our body can get overwhelmed if there are just way too many free radicals. Which also explains why many people are trying to
supplement their bodies with extra antioxidants from the so-called super foods supplements and skincare.
It’s debatable whether antioxidant supplements actually help. Clinical studies have gone both ways on this, probably because it’s hard to control where the antioxidants actually go in your body, so they can even do things like help keep unwanted cells like cancer cells alive. Luckily, a lot of food like vegetables and fruit are high in antioxidants.
As skin is on the outside of your body, they receive plenty exposure to environmental sources of free radicals especially UV radiation from the Sun. It is also one of the parts of your body that can benefit a lot from the extra antioxidants in skincare products.
Though there are currently many skincare products claimed to contain antioxidants on the market, not all of them have fundamental research to support them. Like with any other skincare ingredient whether or not the antioxidants actually help depends on whether they get to the right place to work.
Here are some antioxidants that have studies to back them up.
These are antioxidant enzymes that are naturally present in your skin. Catalase is also promising for helping to prevent gray hair.
Your cells are made of intracellular fluid surrounded by an oily cell membrane, and in between the separate cells there’s also more watery liquid called extracellular fluid. Vitamin C is water-soluble so it’s naturally found inside these watery compartments, the intracellular and extracellular fluid to help protect you from free radicals. Vitamin C is also important for making collagen and works to reduce pigmentation so it’s a really good ingredient for aging and hyperpigmentation prone skin. Pure ascorbic acid has the most proven benefits as antioxidants.
Vitamin E is vitamin C’s oil soluble counterpart and it’s also naturally found in your body in the oily parts like the cell membranes.
Coenzyme-q is an antioxidant important in energy production. Its levels decline with age and it’s a popular supplement for heart health even though it’s uncertain of the actual effectiveness.
Many plants have evolved to have potent antioxidants to protect them from UV since they’re exposed to a lot more UV than organisms that can stand up and walk out of the sun. Some examples of plant antioxidants are polyphenols, flavonoids, isoflavones and anthocyanins.
Some of the antioxidants that you’ll find in skincare that have some studies to support them are ferulic acid, which comes from cereal and is great at keeping vitamin C and E stable. You’ll find the three ingredients combined in a lot of products.
These are potent antioxidants especially epigallocatechin–gallate which has somewhere between 25 and a hundred times the antioxidant ability compared to vitamin C and E. There are other antioxidant polyphenols in tea as well like epicatechin, epicatechin-3-gallate & epigallocatechin. Green and fresh tea will have higher antioxidant content.
Resveratrol is another antioxidant that’s commonly used in both skincare and nutrition and abundantly found in grape skins and red wine.
It is an isoflavone antioxidant that comes from soy products.
This is a red antioxidant that’s found in lots of fruit like tomatoes, watermelons and apricots.
Idebenone is a synthetic variation of coenzyme-q.
Apart from these there are lots more antioxidants that haven’t been tested much yet in clinical trials but have had good results in in-vitro and animal studies. It’s worth remembering that not all studies are well designed and can be biased.
Findings that work in-vitro and in animal studies might not work on human skin also this depends on the formulation of the product. The effectiveness of the product depends on the formulation as well as the active ingredients.
Some of the factors that need to be considered include whether the antioxidant stays active in the product until you apply it to your skin, whether the antioxidant penetrates the skin and gets to where it needs to exert its function and whether enough of the antioxidant penetrates to make a difference.
Unfortunately, there aren’t many reliable ways of measuring the amount of antioxidant a particular product contains and there aren’t many studies on the effects of different formulations, making it hard to compare between different products. The safest bet is to combine antioxidants for better effects. They’re synergistic and can help to replenish each other. For example, in one study a combination of 15% vitamin C and 1% vitamin E protected against UV damage twice as much as vitamin C on its own and adding ferulic acid helped even more.
Antioxidants should also be applied before free radicals form so get them ready before you go out into the sun.