Diets low in caloric density, also called energy density, tend to be more nutritious than those high in caloric density, according to a study published in the "Journal of the American Dietetic Association" in August 2006. Eating mainly food that is low in caloric density also allows you to eat more food while consuming fewer calories, making it easier to lose weight, since you can fill up without going over your daily calorie limit. Compared to some other typical protein sources, tofu is low in caloric density.
Tofu Caloric Density
Foods that have a low caloric density have relatively few calories per gram of food. High-fiber foods and foods that contain a lot of water tend to have a low caloric density, while those that are high in sugar or fat tend to have a high caloric density. Firm tofu contains about 0.7 calories per gram.
Compared to Meat
Broiled top sirloin steak contains about 2.1 calories per gram, while roasted chicken breast provides about 1.7 calories per gram. Steak is three times as energy dense as tofu, and chicken breast is 2.4 times as energy dense as tofu. The much higher fat content of steak contributes to its high energy density. While both the tofu and the chicken breast have similar amounts of fat, the tofu has a higher water content, which is why it is lower in energy density.
Using tofu to replace part of all of the meat or poultry in your main dish will lower the overall energy density of your meal. This is relatively easy to do in casseroles and mixed dishes, but you wouldn't want to serve a chunk of plain tofu alone in place of a chicken breast or steak. On its own, tofu is very bland. However, marinating firm tofu and seasoning it before grilling or browning it in a pan will add flavor. Soft tofu is best for use when it is going to be crumbled, as in scrambled eggs or as a pizza topping, and silken tofu is useful for blending into soups, smoothies, sauces and dips or for making a healthier alternative to cheesecake.
Although tofu is lower in energy density than meat or poultry, you still don't want to eat it in unlimited amounts. Watch your portion size to avoid consuming too many calories. The protein portion of your meal should cover about one-fourth of your plate, with vegetables, fruits and grains each filling one of the remaining sections. Non-starchy vegetables tend to be particularly low in energy density, as are some of the fruits with high water contents.