Is it true that fiber inhibits the absorption of calcium?
Fiber keeps your digestive tract moving, which prevents constipation and wards off ailments like diverticulosis. But calcium bioavailability can suffer if you consume too much fiber. When food speeds through your intestines, there’s not enough time to absorb all the calcium. Another issue: fiber from the husks of grain contains phytic acid, which combines with calcium in the intestines and forms a compound that can’t be absorbed. These problems are unlikely to arise if you get your fiber from food. But unless you’ve been instructed by a doctor to add fiber to food (e.g. by sprinkling bran on cereal), it’s best not to do so because you could easily get too much that way. Again, I want to emphasize that normal amounts of fiber – what you get from a healthy diet – are good for you. The problems arise only from excessive amounts.
