The nutritional value of food does not depend only on the way in which it is cooked. Just as important are shopping wisely for quality products, correct temperature control during storage and preparation and serving food promptly after it is prepared. Leaching effects aside there seems to be little difference to the retention of nutrients between food cooked by microwaves or by conventional means, providing cooking time and temperature guidelines are carefully followed. Care should be taken to avoid overcooking. Radiation and food Food cooked in a microwave oven does not present a radiation risk.
Microwaves cease to exist as soon as the power to the magnetron of a microwave oven is switched off.
They do not remain in the food and are incapable of making either it or the oven radioactive. Chemical changes in foods Consumer concern has been caused by media coverage of isolated reports which suggest that microwave heating produces chemical changes in foods with the formation of potentially toxic compounds. The most widely reported of these was a letter which appeared in the reputable journal The Lancet in 1989. This work was reviewed by an expert committee of the National Health and Medical Research Council which concluded that the results obtained in the experiment were not relevant to the way food is prepared and consumed. A second more recent report in a little known Swiss journal also appears to be irrelevant to domestic use of microwave ovens.