Wednesday, 27 July 2016


What are anti-oxidants? 

Anti-oxidants work against oxidants, or more correctly Reactive Oxygen Species(ROS). 
As we know oxygen is vital for us. But in our body, oxygen molecules can turn into ROS and damage our cells.  ROS is a group of reactive molecules that contain oxygen, and is unstable. Thus to achieve stability it tends to react with our cells, protein, enzymes and other molecules. These reactions often cause damage to our cells, and this damage is called “oxidative stress”. 

Oxidative stress means our body has no sufficient anti-oxidant to fight off the reactive oxygen species. Thus we have damages occurring to our DNA, proteins and other cells.  

It’s widely believed that consuming a large amount of anti-oxidants will reduce the oxidative stress. 

How true is this? 

Food that are rich in Vitamin A, E and beta-carotene are often cited as anti-oxidant food.  

Vitamin A and E are fat soluble vitamin, and is found in very high levels in fruits such as oranges and pineapples. Additionally, many among us take supplements in form of tablets to ensure the take sufficient vitamins every day.  

Anti-oxidants and heart 

Heart issues are a main concern now in developed countries. We are seeing an increasing trend of obesity and heart problems often accompany it. Selenium gained popularity as anti-oxidant with the capability to reduce atherosclerosis (hardening or blood vessels in the heart with fat). 

Selenium is a trace element found in many food. Tuna especially has 92 mcg per serving of selenium. Many other dairy products and cereal have high amount of selenium as well.  

Is selenium effective in preventing heart disease?  

A group of researchers from Cochrane collaboration pooled 12 researches that were done on this topic. After carefully looking at all the studies done on this issue, they concluded that selenium has no benefits in reducing heart diseases. But interestingly, selenium is reported to increase the risk of getting diabetes mellitus. But the risk is not strong enough for us to have any firm conclusion.  

But, we can safely conclude that as of now, Selenium has no benefits nor risk in regards to cardiovascular health. The authors of the research paper concluded that it’s not necessary for a well-nourished adult to take Selenium for heart protection.  

Vitamin E is also a fairy popular anti-oxidants taken by many. Another study done by a group of scientists from UCLA, pooled a total of 84 researches done on effect of Vitamin E on cardiovascular health. Again they concluded that Vitamin E supplementation does not protect us from heart problems.  

Anti-oxidants and Cancer 

Image by |Pixabay

Vitamin A is found in food like fish oil, milk and egg. Does it help in cancer prevention? One group of scientists looked into the claim of Vitamin A being a protective agent against bladder cancer. They concluded that eventhough the researches are showing Vitamin A to be protective against bladder cancer, no consensus can be reached in regard to how much Vitamin A is needed and what’s the best way to take it.  

Furthermore, do we all have to take Vitamin A to prevent bladder cancer? Who are the ones with high risk? Without answering these questions, taking Vitamin A daily might not be very beneficial. Not much studies have been reported for other types of cancers.  

In conclusion, taking supplements for its antioxidant activity has not been proven effective in preventing illness especially heart diseases and cancer. But daily requirement of vitamins in the form of food should be taken regularly as a general health measure.  

For further reading:  

  1. Selenium – Health Info 

  1. Vitamin A – Health Info 

  1. Vitamin A and Bladder Cancer 

  1. Vitamin E and cardiovascular health 

  1. Selenium and cardiovascular health 

No comments:

Post a Comment