Antioxidants: hope or hype?

Throughout our life, our health is faced by many threats such as starvation, infections, toxins, inflammation etc. Amongst these threats, one of the most frequent is a threat from free radicals. These ‘free radicals’ are chemicals which are formed as a by-product of digestion, exercise, exposure to toxins, smoke, pollution and radiations. Free radicals have an appetite for free electrons and would take it from near-by molecules which may cause alteration in the structure and function of the donor. Recent studies uncover protective properties of free radicals in fighting infections but excessive amounts can be damaging and can cause oxidative stress on our body. Actions of free radicals may alter DNA strands leading to premature ageing, cause LDL cholesterol to accumulate in arteries, and change functioning of cell membrane and affecting flow of nutrients.

Antioxidants are protective substances which quench free radicals by donating electrons and hence other molecules are spared. They are also involved in DNA repair mechanisms and maintenance of cell health. We consume antioxidants from food as well as produce them naturally. There are probably thousands of antioxidants found in foods such as vitamin A, C and E, beta carotene, and minerals like selenium and manganese. Antioxidants are specific in their activity which means they can’t be used interchangeably therefore having a varied diet is essential.

The hype:

In 1990s, antioxidants gained spotlight when scientists were trying to find links between free radicals and chronic diseases like atherosclerosis, cancer and vision loss. Epidemiological findings showed that people consuming more fruits and vegetables had less risk of developing these diseases which propelled studies on protective effects of single antioxidants in supplement form against these diseases. And as always, to promote their products the media and the food industry started inflating the health benefits of antioxidants before any conclusive results were concluded by studies. From teas and frozen fruits to supplements, all sorts of products were marketed with the labels “antioxidant rich” to capitalize on the incomplete information their consumers had about their health benefits.

Further, scientists are not sure if antioxidants are the actual heroes. While there are evidences suggesting reduced chronic health risks associated with consumption of more fruits and vegetables, it is unclear if they are due to antioxidants, other plant compounds or their combination.

What the science says:

There are two major findings of multiple studies conducted in recent times, first is that the touted health benefits may not be as promising as we might think they are; secondly, eating whole fruits might be a better solution than popping antioxidant supplement pills. Scientific findings show no substantial positive effect of antioxidant supplements in protecting against cardiovascular disease and cancer, on the contrary, one study on beta-carotene supplement shows increased risk of developing lung cancer and another finds vitamin E supplements to be associated with higher risk of hemorrhagic stroke. While in case of age-related eye diseases, supplements containing a combination of antioxidants showed some promising results.

Are supplements superior?

It is clear that supplements don’t work like magic to fix your poor diet and lifestyle but the effects of antioxidant supplements is especially disheartening. Consuming antioxidants in from of whole fruits and vegetables is exponentially efficient in quenching free radicals probably because other plant chemicals like polyphenols work in conjunction to improve functioning of vitamins and minerals, plus one fruit may provide numerous other nutrients and antioxidants as compared to limited amounts in a pill. Another important factor is availability of different forms of same antioxidant in natural foods in contrast to one form in a tablet. As said earlier, antioxidants are specific in function and therefore different forms of the same will have different functions in the body.

The takeaway box

Food and supplement manufacturers have long been using the distorted perception about antioxidants as a marketing tool for their products which as a result fuelled the misconception further by inflating beneficial effects of antioxidants. While it is true that eating antioxidant rich fruits and vegetables reduces chronic disease risks such as cancers, heart disease, and macular degeneration it is not clear whether only the antioxidants are the real defenders or if other compounds work in unison. This perplexity rises from the sub optimal efficacy of supplements in comparison to natural fruits as per current research data. If you are considering taking a supplement, then I would highly recommend that you have a discussion first with your doctor, especially if you are pregnant or thinking about giving your kids a supplement; also keep in mind that having a supplement is not going to balance an unhealthy diet. Supplement consumption can hinder with your current medication or may lead to toxicity due to over accumulation of fat stored vitamins and minerals.


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