We’ve all heard them mentioned, but what, exactly, are ‘free radicals’?
You may remember that atoms are held together by paired electrons, in what is called a chemical bond. This chemical bond is what keeps a molecule stable.
So, when an electron is unpaired, i.e. when the chemical bond is broken, the molecule turns unstable. It is now highly reactive. That’s a free radical.1
Why does this happen? Mostly, perfectly natural processes. For example:
- When the body converts food into energy, chemical bonds are broken (and formed).1
- Free radicals are sometimes needed in order to send signals to other cells.2
- They are also created by the immune system to fight off harmful bacteria and viruses.3.
Here’s when this becomes a problem, though: the UV rays of the sun, pollution, cigarette smoke, etc. also break chemical bonds, leading to the creation of even more free radicals.
Why is having too many free radicals in the body a bad thing?
Free radicals are very reactive. They attack the nearest stable molecule, “stealing” its electron, desperate to stabilise once again. When the “attacked” molecule loses its electron, it becomes a free radical itself. This begins a domino effect, resulting in the ultimate disruption of a living cell.
Cell damage by free radicals is the underlying cause of ageing and a number of diseases (eg. Arthritis, cancers, atherosclerosis, Parkinson’s disease, etc.).4
Luckily, there is a way to stop free radical damage: through antioxidants.
Antioxidants neutralise free radicals by ending the electron-“stealing” reaction. They donate one of their own electrons. After donating an electron, they don’t become free radicals themselves, because they are stable in either form.1
Where do antioxidants come from?
The body produces them to protect itself. However, when environmental factors increase the number of free radicals, the body cannot cope, and diseases ensue.
You can’t do much about the environmental factors, but you can help your body protect itself from them, through antioxidant-rich foods or supplements.
Vitamin C, vitamin E, beta-carotene, and lycopene are some examples of the antioxidants we can find in foods and supplements. Research is also busy finding new sources of antioxidants, given the ever-increasing need for protection from environmental factors. Also, not all antioxidants are created equal. For instance, scientific evidence suggests that the antioxidant power of an extract from grape seeds is 20 times greater than vitamin E and 50 times greater than vitamin C.5
As science continues to investigate other potential ways in which we can prevent free radical damage in the body, one thing is already abundantly clear: there’s every reason to consume as many and as wide a variety of antioxidants as you can!
1. Lobo V, et al. Pharmacognosy Reviews 2010, 4(8): 118-126.
2. Ray PD, et al. Cellular signalling 2012, 24(5): 981-990.
3. Yang Y, et al. International reviews of immunology 2013, 32(3): 249-270.
4. Kammeyer A, and Luiten RM. Ageing research reviews 2015, 21: 16-29.
5. Shi J, et al. Journal of medicinal food 2003, 6(4): 291-299.