It is important to read the label on foods to be sure of the nutrition value. Tofu can be an excellent source of calcium, but not all types of tofu are. Most tofu that is processed with calcium sulfate has about 260mg of calcium per cup. The body absorbs calcium sulfate just like it takes calcium from milk.

The alternative is tofu that is processed with nigiri, which has very little calcium. Similarly, calcium-fortified soy milk contains 300mg of calcium-equal to a cup of milk-but again you want to double check the label before you purchase soy milk because not all brands are fortified.