There has been concern previously that too much protein in your diet may increase calcium loss, however Dr. Gabe Mirkin points out that further research shows that it might do just the opposite:

Reports in the American Journal of Clinical Nutrition (Volume 78, Issue 3, 2003) showed that eating plenty of protein and lots of foods from plants helps to keep bones strong. Most scientists now feel that a very low-protein diet can cause osteoporosis, while a moderately high-protein diet may help to prevent it.

So go enjoy that steak!