Contrary to urban legend, consuming more protein does not cause your bones to lose calcium. Nutrition Diva explains why.
“Ever since my wife heard your episode on the benefits of protein for preventing muscle loss as you get older, she’s eating more eggs, meat, and fish, especially at breakfast and lunch. But doesn’t a high protein diet weaken your bones? Do we have to choose between strong muscles and strong bones once we get past middle age?”
Actually, it’s just the opposite, Ely: Protein contributes to strong muscles AND strong bones.
Does Protein Cause Bone Loss?
The concern about protein and bone health may stem from the fact that when you increase your protein intake—especially from animal sources—the amount of calcium in your urine goes up. The assumption has always been that this urinary calcium was being taken from the bones in order to buffer the acid residue that remains after digestion of meat and other animal products.
See also: Ph-Balancing diets
Obviously, if something you are eating is regularly causing the calcium to leach out of your bones and into the toilet, over time this is going to be very bad news for your bones. However, this is not at all what is happening.