Do Microwaves Zap Away Nutrients from Food?

It is difficult to imagine days without using the microwave in today’s fast paced world. Every one is in some or the other hurry and they prefer using microwave in order to save time. You are most likely to use it at least once a day as cooking in microwave is much faster and easier.
But as a matter of fact, certain questions arise in our mind from time to time regarding the effects that the microwave cooking can have on the foods. At times you may also compare it with traditional cooking to see what exactly is the difference in the nutritional value of food cooked by these two different methods.

The issue regarding the nutrition loss:
We get important vitamins, minerals and antioxidants such as Vitamins B, C and D, potassium, calcium, iron and magnesium from the vegetables we eat and all of these help us to stay healthy and fight against various diseases.
Apart from these benefits, large amount of sulphur containing compound is present in cruciferous vegetables like broccoli, cauliflower and cabbage.  These compounds are considered to be very helpful in fighting against cancer.
There has been concern about the possibility of nutrients being depleted by the use of microwaves to cook food and it goes without saying that we could be at high risk for various diseases if we do not get the nutritional values from the vegetables.
However, credible sources such as American cancer society and European food information council believe that microwaves are a nutritious way to cook. According to them, water molecules in the food are vibrated by microwaves by way of which they achieve the magic of fast cooking and in most of the cases, lesser the time for which food is exposed to heat, higher the nutrient levels. If you consider tea, only water is microwaved and the tea bag is added later, there could be no adverse affect on the nutrients.

How big is the nutrient loss, if there is any?
Loss of nutrients can anyway happen if you heat the food. Certain component of food gets broken down which leads to changes in chemical makeup if the food is exposed to heat. This can result in a decrease in their concentration or in their availability to your body for few nutrients. Water soluble vitamins such as Vitamin B, C and folic acids are most sensitive to heat.
Studies show that nutritional values of veggies tend to decrease by all ways of cooking like boiling, steaming, microwaving, stir frying and it seems to be the highest if foods are unprocessed.
A study showed that Vitamin C content of any food is decreased by 20% to 40% when cooked in microwave as compared to the raw vegetable. However, good news for the microwave users is that it is not the worst cooking option and boiling and stir frying tend to cause greatest nutritional loss as larger amounts of water are typically used and vitamins are leached out because of this.

The Bottom Line
The nutritional content in food is affected more by factors such as cooking time, temperature and amount of water much more than the method of cooking.
Microwaving may be the best option as the time taken by it to cook food is very less which means your food does not get exposed to heat for long, thus causing minimal nutritional loss.

Source: http://grist.org/living/ask-umbra-does-microwaving-vegetables-zap-their-nutritional-value/
Source: http://www.oprah.com/health/The-Truth-about-Eating-Microwaved-Food
Source: http://bodyandhealth.canada.com/channel_section_details.asp?text_id=5493&channel_id=9&relation_id=26047