6 Foods That Weaken Bones: Page 3
The numbers for caffeine aren't as bad as for salt, but caffeine's action is similar, leaching calcium from bones. For every 100 milligrams of caffeine (the amount in a small to medium-sized cup of coffee), you lose 6 milligrams of calcium. That's not a lot, but it can become a problem if you tend to substitute caffeine-containing drinks like iced tea and coffee for beverages that are healthy for bones, like milk and fortified juice.
What to do: Limit yourself to one or two cups of coffee in the morning, then switch to other drinks that don't have caffeine's bone-sapping action. Adding milk to your coffee helps to offset the problem, of course.