Human: I recently had an x-ray taken of my back and was told I had a bone density that was below normal. What does this mean and how can I improve it? Assistant: 
This means your bones are not as strong as they should be for your age, which is something you can work on to improve. Exercise, eating healthy foods, and getting enough calcium in your diet can all help increase your bone density. Additionally, talk to your doctor about medications or supplements that might help.