Microwave-heated foods lose nutrients?

What we are talking about, the first thing is to know how a microwave oven works. Heat is a transfer of energy at the molecular level that results from an increase in the movement of molecules of a substance. In other words: to heat any food, you have to vibrate its molecules and, because of the friction that results, its temperature increases.

When it is heated in a pan or in a conventional oven, the heat is transmitted to the outside of the food, and the inside will be cooked when this outside heat is transferred to the oven. # 39; inside. However, with the microwave, all foods are heated at the same time, and for this we use microwave waves that vibrate in unison with water and other polar molecules. of food.

In short, from a physical point of view there are no big differences in how to heat foods. As Luis Jiménez, a chemist and scientist, explains, "A microwave raises the temperature by vibrating the polar molecules with microwave radiation, and a conventional oven makes it more beastly, generating a lot of heat." in some resistances. by proximity and infrared radiation. In fact, it is easier to reach very high temperatures in a conventional oven, which could be a risk factor for destroying certain nutrients.

Many scientific articles have compared the nutritional quality of different food methods and show that there is no problem in using the microwave oven. A review published in 1982 in the journal CRC Critical Reviews in Food and Nutrition Sciences has analyzed all existing literature in this regard concluding that there are no significant differences between conventional methods and microwaves.

Any method of cooking leads to the loss of nutrients

"The destruction of nutrients has more to do with the amount of water used for cooking and the temperature reached in the kitchen", explains Marian Alonso -Cortés, dietician-nutritionist and head of training at Aizea. "And, precisely, in the microwave, there are the factors that reduce the loss of nutrients, especially vitamins and minerals, because usually little water is used, it is Water itself who cooks it. " For example, a study published in 2009 in the Journal of Food Science found higher levels of antioxidants in some foods in the microwave such as onions and asparagus. In fact, this method could be compared to steaming, one of the most respectful of the nutritional quality of food.

In short, and as the nutritionist recalls, "any mode of preparation that involves immersing the food in water or heating it will result in a loss of nutrients. For example, vitamin C or proteins undergo a process of denaturation and transformation, but this happens with any method. "

So, if you want to preserve the quality of a whole food, you have to eat it raw., You can use the microwave without any type of repair.