1 Visual acuity (sharpness) tests help your doctor find out if you have a problem that affects how well you can see. 2  They measure the eye's ability to see details at near and far distances. 3  The tests usually involve reading letters or looking at symbols of different sizes on an eye chart.
Amount of calcium. Elemental calcium is key because it's the actual amount of calcium in the supplement. It's what your body absorbs for bone growth and other health benefits. The Supplement Facts label on calcium supplements is helpful in determining how much calcium is in one serving.
More research is needed before doctors know the effect calcium supplements may have on your heart attack risk. The calcium supplements that some doctors are concerned about are those that contain only calcium â not supplements that combine calcium and vitamin D or multivitamin supplements.ome doctors think it's possible that taking calcium supplements may increase your risk of a heart attack. Other doctors believe that calcium supplements have little or no effect on your heart attack risk.