Tuesday, April 26, 2011

Free radicals,antioxidants and ORAC

We’ve all heard about free radicals and the damage it causes the body-but how many of us actually know what free radicals are and how we can prevent/reduce the damage caused by it. Free radicals are oxygen molecules that have lost an electron and hence become highly unstable and extremely reactive. In this state it tries to grab an electron from any atom that it is close to, so that it can become stable again. This sort of starts a chain reaction as now the other atom has lost an electron and has become a free radical and needs to find an electron itself to become stable. This kind of grabbing of electrons within our body causes a lot of damage. Free radicals are created as natural by-products of the various reactions in our body as well as due to exposure to cigarette smoke, air pollution, and UV light or radiation. It is said that on an average, every cell in our body comes under attack from a free radical once every ten seconds. So how do we stop/prevent/reduce this damage? The answer lies in something known as antioxidants.
Antioxidants are substances or nutrients found in food that may help in protecting or slowing the damage caused by free radicals to our bodies. These antioxidants are thought to act as ‘free radical scavengers’ and provide them with the extra atom that they need. By doing so, the free radical become stable and also stops the chain reaction. Although there are some enzyme systems within the body that scavenge free radicals, the principle micro nutrient antioxidants are said to be vitamin E, beta-carotene, and vitamin C. Additionally, selenium ( which is a trace metal that is required for proper function of one of the body's antioxidant enzyme systems) is also included in this category.
Since the body cannot manufacture these micro nutrients, they must be supplied by our diet. Foods that contain antioxidants are measured by ORAC (Oxygen Radical Absorbance Capacity). Though this theory hasn’t been proved, nutrition researchers estimate that a person needs to consume around 3,000 to 5,000 ORAC units every day for our blood levels to maintain a good antioxidant defense system.
Here are some foods and the ORAC Value/100g:
Pomegranate:3,307
Raisins:2,830
Blueberries:2,400
Strawberries:1,540
Spinach:1,290
Plums:949
Broccoli:890
Beetroot:840
Oranges:750
Red grapes:730
Cherries:670
Brinjal/eggplant:390
Carrots:207
String beans:201
Tomatoes:189

You don’t have to memorize these values, just remember to eat a variety of colored fruits and vegetables. The more colorful your diet (naturally colorful-not by the addition of food colors) the more you will benefit. Don’t limit yourself to just the vegetables and fruits mentioned in the list-others can have their own special benefit.
The rule of the thumb should be to include as many seasonal (and fresh) fruits and vegetables as possible.

Q)What is your favorite antioxidant rich fruit/vegetable?

3 comments:

Rebecca from Chow and Chatter said...

informative post, miss your posts, I like blueberries

Rohini said...

super Shweta! Aaj samaj mein aaya!! I am still following your advice on eating lots of coloured fruits and veggies!! What all happens in our body man, OMG!

Mother Rimmy said...

Terrific post. You've explained the role of free radicals in such a way as it is easy to understand. Kale is tops on my list of greens. It's cheap and stand up well when cooked.

Kristi