Introduction To Antioxidants and Free Radicals
Antioxidants, a term that marketers and advertisers have bombarded the the public with, is probably not a foreign term to many. However, despite the best marketing tools many people still are not sure what an antioxidant actually is, where to find it, or why we should be consuming them, and what are the benefits of antioxidants. Well, before we talk about antioxidants, we need to talk about the reason for the existence of antioxidants and its arch nemesis- free radicals.
What Are Free Radicals?
Free radicals are molecules and atoms in the body that are unstable and have the potential to cause damage in the body. When molecules are unstable they are able to cause damage by stealing pieces from DNA, proteins, and cell membranes in order to stabilize themselves. When healthy DNA, proteins, and cell membranes becomes destabilized and loose vital pieces of their structure they lose their ability to function normally, and when a cell is damaged extensively the cell eventually dies. Therefor unwanted and excess free radicals in the body can cause long term damage to your health and can be the cause of a myriad of diseases such as as cancer, autoimmune disorders, rheumatoid arthritis, cardiovascular and neurodegenerative diseases.
Causes Of Free Radicals
There are many different causes of free radicals, and free radicals can be produced in different ways. Our bodies naturally make free radicals during the electron transport chain, which is a microscopic system within your cells that essentially creates energy for the body.
However, there are many other different causes of free radicals that are not natural. Things such as UV light from the sun, air pollution, radiation, pesticides and chronic inflammation can all cause increased production of free radicals and therefor increased cellular damage. Other self induced factors of free radicals include smoking, certain drugs, and excessive exercise.
So again, what is an antioxidant? Well, simply put, an antioxidant neutralizes free radicals by donating a piece of themselves to the free radical and therefor negating the harmful effects that the free radical is capable of doing to the body. Essentially antioxidants sacrifice themselves for the greater good, the unsung heroes if you will. There are possibly thousands of antioxidants but we can put them into two categories:
- Antioxidants that our bodies make naturally including superoxide disputes, catalase, and glutathione systems.
- Antioxidants that we consume in the form of food or supplements. Food and supplement forms of antioxidants is especially important if you are exposed to the various causes of environmental or behavioral sources of free radicals as mentioned earlier. There are actually hundreds if not thousands of antioxidants but some of the more well known ones include: vitamin C, vitamin E, beta-carotene, phytoestrogens, selenium, magnesium.
Antioxidants in Foods
Foods can be measured for their ORAC (oxygen radical absorbance capacity), and a high ORAC amount is desired and is indicative of a high antioxidant quantity. At one point the USDA recommended 3,000-5,000 ORAC units per day. However, unlike other nutrients there has never been a hard and fast rule as to how much we need in order to prevent diseases or how much is needed for optimal health. What is interesting though is that in 2012 the USDA stopped using ORAC – a controversial move that has left more than one researcher disagreeing. One of the main reasons why the USDA stopped using the ORAC is because manufacturers and marketing campaigns were using them incorrectly and misleading the public in order to promote their specific products. Although the USDA has stopped using the ORAC, it is still a very handy tool to quantify which foods contain a high ORAC amount. Below is a list of the top 20 foods with a high ORAC value:
In summary, we at Mr and Mrs Nutritionist recommend eating a very wide variety of foods, including foods with a high ORAC score. Also if you are exposed to many sources of free radicals you should definitely increase your consumption of foods high on the ORAC score. It should also be noted that not all antioxidants are the same, and different foods contain different types of antioxidants, so try and get a large variety of high ORAC foods into your diet in order to neutralize excess free radicals.
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