Some reports of osteoporosis in people who have a long history of eating a dairy-free natural food diet have caused some concern in the natural foods community. Although health statistics for people eating a mostly vegetable based diet are good, cases of low bone density have been reported. Since Americans get about seventy percent of their calcium requirements from dairy products, nutritionists assume that low bone density is caused by the absence of dairy products in vegan diets. However, according to a report published by the Japan Federation of Miso Manufacturers Cooperative, almost ninety percent of the calcium in the traditional Japanese diet comes from non-dairy sources, particularly miso soup. A bowl of miso soup with tofu, sea vegetables, and a little fish contains about 233 milligrams of calcium. What's more, miso is known to facilitate the absorption of calcium and other minerals. Eating miso along with other high calcium foods can be an alternative to the use of dairy products or medications to increase bone density. In fact, daidzein, another isoflavone found in soybeans, is very similar to the drug ipriflavone, which is used throughout Europe and Asia to treat osteoporosis.