Milk is good, but then milk is bad. Margarine was good, now it's bad. Red meat is fatty, fish uninspected and chicken carries salmonella.

In the latest piece of nutritional revisionism, a preliminary Agriculture Department study Wednesday said margarine increases blood cholesterol levels, a risk factor in heart disease. Last week, we heard that milk may be bad for some children.

Don't read while you eat and don't believe everything you read about eating, says Robyn Webb, nutritionist and cooking instructor, because keeping up with all the warnings about food can make your head spin and stomach ache.