In these cases, vegan foods can be extremely helpful in filling in dietary gaps. The trick is to use products that are quick and simple to prepare, and can be easily exchanged for animal products in familiar dishes. The vegan can substitute nutritious plant-based foods for most of the common dairy products. Getting sufficient iron, calcium, and vitamin B 12 is a particular concern with vegan diets. Vitamin B 12 can be obtained from fortified cereals and fortified soy beverages, or a vitamin B 12 supplement.
Macrobiotic diets are generally too restrictive for people with cancer, especially during treatment.
The more limitations placed on the diet of a person who is experiencing eating difficulties or who may already be malnourished can set the stage for additional problems. For those with an increased sense of strong or bitter tastes, the mild flavor of some soy products can be a welcome change. If taste blindness is a problem, using marinades and seasonings for tofu and tempeh can enhance the flavor. Dry beans and peas, nuts, peanut butter, and seeds are examples of foods used sparingly or infrequently by non-vegetarians. These foods and snacks can be utilized frequently by vegans to supply a greater percentage of calorie and protein requirements.