What do antioxidants actually do?



What is oxidative stress and why do we need antioxidants? 

Our cells are powered by small factories (of bacterial origin!) called mitochondria which create energy from a series of chemical reactions. An important part of this energy production is the creation of reactive oxygen species (ROS) which are a by-product of normal metabolism, but need to be kept in check. 

Antioxidants play an important role helping to 'mop up' ROS, keeping them within a healthy range for the chemical reactions to take place without causing the cell too much damage. A good way to think about this is with the analogy of a home, which needs a good fire to produce heat and energy for cooking, warming water etc. If that fire is not given sufficient oxygen supply or good wood as fuel, it will burn with a thick, black smoke or worse it’ll get out of control.

Eating plenty of antioxidant rich foods ensures we have a good supply of antioxidants on hand to mop up the ROS, especially after illness or exercise or a stressful week at work - all of which require extra energy and therefore produce more ROS. Antioxidants are typically found as polyphenols in fruits and vegetables, vitamin C is an obvious example, and we have anthocyanins in purple berries and oleuropein in extra virgin olive oil all contributing to a healthy balance.

We don’t want to completely wipe out ROS - they form an important part of our immune system’s ability to respond to intruders and we know from clinical trials that having too much of an antioxidant such as vitamin E can be harmful. The key is to make these chemicals available to our cells in a natural form found in whole plant foods and Indi supplements.



Dr Federica Amati is a powerhouse of evidence-based knowledge and information. She holds a PhD in Clinical Medicine Research from Imperial College London and is a registered Nutritionist with the Association for Nutrition. She is also actively involved in nutrition, physical activity and mental wellbeing research at Imperial College London; and cardiometabolic health and COVID-19 and nutrition research with NNedPro, a global think tank founded at Cambridge University. Alongside her research and private client consultations, she is also Chief Nutrition Scientist for Indi Supplements. 

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