- Free radicals (ROS and RNS) are unstable molecules with one or more broken pairs of electrons. Antioxidants are elements that neutralise damage causing free radicals in our bodies.
- Endogenous antioxidants are internally produced in our bodies, exogenous antioxidants are consumed externally in diets or as supplements.
- Antioxidant paradox refers to the theory that exogenously consumed antioxidants might have no real impact on neutralising free radicals. Hence deeming antioxidant supplements unnecessary.
What are antioxidants? Why do we need to them?
In the simplest of terms, antioxidants are molecules that fight or neutralise the free radicals in our bodies. Antioxidants are present in their natural form in many fruits, vegetables and other consumable items.
You may come to wonder about these free radicals whose neutralisation is required to preserve our health. As you all must know our bodies are made up various cells. Each of these cells in turn is made of molecules which further comprise of pairs of electrons. So, when a pair of electrons gets broken, the molecule itself becomes unstable and is referred to as a free radical. There are majorly two types of free radicals, namely reactive oxygen species (ROS) and reactive nitrogen species (RNS). They are also collectively referred to as ‘reactive species’.
The causes for the breaking of the pair of electrons and hence the formation of free radicals are numerous. They vary from our body’s normal metabolic process, to oxygen consumption (i.e. breathing), smoking, and exposure to pollutants and so on. Note that since breathing (oxygen consumption) results in free radicals, those who exercise are at a greater risk of oxidation as oxygen consumption is more intense during workouts.
Getting back to free radicals- a molecule that has become unstable by loss of an electron starts seeking ways to become whole again. In the process of trying to become whole again it begins damaging other healthy molecules, by stealing an electron from them. This sets of a chain reaction where every subsequent free radical tries to make whole by breaking another healthy pair. This process can become overwhelming and lead to serious damage. The loss of an electron alters the molecule’s structure and even its functionality by altering the instructions coded in the DNA strand. An excessive amount of these free radicals in the body is a condition referred to as oxidative stress. This may lead to some serious chronic diseases if not dealt with . Thus there is a need to neutralise these free radicals.
But, don’t worry, the situation isn’t as grave as it seems. That’s because the human body isn’t completely defenceless against free radicals. Just like its ability to fight against infections by producing antibodies, human system generates antioxidants to fight off these free radicals. The antioxidants produced by the human body are referred to as endogenous antioxidants.
Antioxidants scavenge these free radicals and rid our bodies of them or neutralise their effects. Hence when fitness professionals or consumer product companies tout out that antioxidant supplementation is essential; it does make a lot of sense. But wait; don’t go off buying your share of antioxidant supplements just yet. Because there is still a lot that needs to be noted and discovered about antioxidants, their supplements and their impact.
Types of antioxidants
As mentioned above, human body naturally produces antioxidants which are referred to as endogenous. Glutathione (GSH), Superoxide Dismutase (SOD), Alpha Lipoic Acid (ALA), Coenzyme Q10 (CoQ10), and Catalase are the most potent endogenous antioxidants . Though this natural reaction exists, a problem arises when free radicals cannot be checked by endogenous antioxidants alone.
The other type of antioxidants is exogenous, the ones we consume externally via our diets or in form of supplements. Generally speaking when someone mentions ‘antioxidants’, they are usually referring to exogenous ones. However, the term ‘antioxidants’ is extremely broad and consists of numerous subcategories. Each of these subcategories further contains different types of antioxidants . Some of the most commonly known antioxidants are vitamin C, vitamin E, beta-carotene, flavonoids etc.
What is the antioxidant paradox?
Now we know that free radicals are harmful to our bodies, can cause excessive damage and can even be the cause of many fatal diseases. We also know that antioxidants are helpful in neutralising these free radicals in our body. This observation forms the perfect basis for the antioxidant supplement consumption bandwagon. Even though the benefits of consuming exogenous antioxidants seem logical and tempting, this isn’t the complete picture.
The other side of the picture, which the antioxidant supplement propagators forget to mention is a little something called the antioxidant paradox. The paradox in question refers to the fact that even though antioxidants are meant to neutralise free radicals, most studies indicate zero or marginal impact of dietary/ supplementary antioxidants as preventive measure against the ill effects of these free radicals .
While the antioxidant bandwagon-ers cheer for inclusion of antioxidants as supplements in diets and as supplements, research have been hard at work to make real sense of the whole ordeal.
As per claims, antioxidants can improve one’s cardiovascular health and protect against heart diseases and strokes. Studies however suggest that antioxidants like vitamin E, beta-carotene and others do not impact rate of cardiovascular disease . Next comes the impact of antioxidants on cognition. The studies for this are neither here nor there. One of the studies suggests that a long term supplementation of antioxidants over at least 15 years shows cognitive benefits . But another study finds vitamin E and/ or selenium supplementation of be ineffective in protection against dementia . Many also believe that antioxidant supplementation is preventive against cancer or cancer causing agents. The studies however paint a completely inconclusive picture. As per one study beta-carotene has not effect on cancer rates in men. Another study indicates reduced risk of cancer in men given a cocktail of antioxidants, while no such impact of women taking the same concoction .
Antioxidants supplementation and exercising
Many fitness professionals and athletes promote the use of antioxidant supplements to counter excessive oxidative stress endured during workout sessions. Again, on paper, antioxidant supplementation seem to the most logical way to go. But studies and research do not paint a completely rosy picture when it comes to benefits from these supplements.
For example, a review of studies assessing the impact of vitamin C supplements on exercising indicates and its ability to reduce oxidative stress. None of the studies in the review however, indicated absolute effectiveness of vitamin C supplements in the matter . Another antioxidant N-Acetylcysteine is expected to help synthesis endogenous antioxidant- glutathione. And as per some studies it actually does increase endurance and skeletal muscle function . The studies also suggest that it enhances endurance only during moderate-intensity and submaximal exercises, with lesser impact during high intensity works. However, there may be severe side-effects of this antioxidants.
Some athletes and fitness professionals favour antioxidant supplementation in hope of reducing soreness, muscle damage and promote recovery. And as a per review study, vitamin C and E, may actually favourably counter oxidative stress induced ill effects . However it is also important to note that these results are neither consistent nor positive all round.
A reason why one may hold off on these supplements is that, while they may somewhat enhance endurance, recovery and blood flow, they may also be counterproductive. As per a study, these supplements may inhibit muscle hypertrophy related signalling pathways. Many experts go off of this and go to completely shun these supplements for blunting hypertrophy. However even the research concerning this aspect is not sufficient to draw strong conclusion.
Then again since antioxidants is an umbrella term with numerous subcomponents, and the research we have remains insufficient. With the results of most of whatever studies we have being inconsistent, there is no way to establish and impose a strictly positive or negative opinion about antioxidant supplementation. So where does that leave us now?
Well, there is no definite answer as is evident by research (or lack thereof). That being said, another thing that is pretty obvious is that- there is no harm in being conscious of eating food with natural antioxidants. The most logical way to proceed is to consume a well-balanced diet comprising of enough fruits and vegetables to fulfil antioxidant requirements. It is also advisable to discourage from antioxidant supplements, till the time there is enough evidence to disregard their ill effects. Or there is stronger evidence highlighting clear and consolidated benefits of these supplements.
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