Microwaves can be safe, efficient way to cook

Q Is microwave cooking safe? I have been working with a registered dietitian who says that it is not safe, and that we should return to traditional cooking methods. An Internet search on "microwave cooking and health risks" produces hits that generally support this conclusion. What is the best current advice?

A There are many urban myths about microwaving, said Julie Jones, a registered dietitian and professor emeritus of food and nutrition at St. Catherine University in St. Paul.

Microwave heating is not harmful, according to the U.S. Food and Drug Administration. Microwave ovens can be used safely, as long as the oven gasket is kept clean and microwaves do not leak out of the oven. Microwave cooking, using proper cooking times, has been shown to have little impact on the nutritive value of milk, meat or eggs.

"The only reason that I can think of as to why a dietitian would suggest that you not use a microwave would be to discourage a diet high in pre-prepared foods that are high in salt, sugar and fat," she said.

Jones said that microwave ovens offer a number of advantages:

• They cook and reheat food quickly and are more cost- and energy-efficient than traditional methods.

• They do not require pre-heating.

• They often mean less cleanup and fewer dishes.

• They offer nutritional benefits in cooking certain foods. For vegetables and legumes such as chickpeas, the short cooking time and minimal water requirement means that more nutrients are retained and protein is more accessible. Bacon cooked in a microwave oven produces fewer nitrosamines, a potential carcinogen.

Microwave ovens also have disadvantages:

• They do not cook certain foods, such as boiled eggs.

• Care must be used in cooking protein foods because they can become tough.

To microwave safely, use proper containers:

• Avoid using plastics that have not been designed to undergo the heat of a microwave, such as used margarine containers.

• Take care with ceramic pottery because it contains metals and can get very hot.

• Don't use paper products that contain dyes.

• Don't use metal containers, as the metal can cause arcing, which blocks the microwaves and prevents heating.

• Stirring or rotating food so that it is thoroughly cooked. Always check pork, for instance, to make sure that it is not pink in spots.

• Taking special care with semi-liquid foods, which can have what is known as a volcano effect. They superheat, appear to erupt when stirred and can cause burning.

• Making sure that any raw ingredients in pre-packaged, but uncooked, processed foods are fully cooked, not just warm enough to eat.

• Realizing that cooking times and temperatures will vary because different ovens have varying power levels.

• Avoiding heating baby foods because the uneven heating could leave some parts of a pureed food cold and others hot enough to burn the baby's mouth.