Those who suffer from a peanut allergy must be ever vigilant. In an earlier column on foods and cancer, you advised staying away from foods with nitrates, such as hams and sausages. But now I've noticed the deli turkey and roast beef we buy for sandwiches has nitrates. Food processors use nitrites as preservatives in cured and smoked meat products, such as bacon, sausage, smoked and deli meats. These additives are used to help prevent botulism, an often fatal food poisoning.
Nitrites represent a risk, as they can form cancer-causing chemicals called nitrosamines.
Nitrates, on the other hand, occur naturally in several vegetables, including turnip greens, beets, celery, rhubarb, spinach, radish, parsley and lettuce. They represent less of a risk than nitrites, but a nitrate can be converted into a nitrite in the stomach. This means that nitrosamines can, theoretically, form in the stomach when you eat a nitrate-containing vegetable and a protein food at the same meal. The important difference is that antioxidant nutrients can help limit nitrosamine formation. These nutrients, such as vitamin C, E or antioxidant phytochemicals, are often found in nitrate-containing foods.