According to a 2013 Norwegian study, drinking water with a high amount of magnesium protects against hip fractures.
Researchers followed over 700,000 men and women for a period of seven years and recorded 19,000 hip fractures.
If the water in an area contained a lot of magnesium, the people drinking it were less likely to suffer from a hip fracture.
There is not much magnesium in drinking water. However, magnesium deficiency is widespread, which may have also been a factor.
"An inverse association was found between concentration of magnesium and risk of hip fracture in both genders (IRR men highest vs. lowest tertile = 0.80, 95% CI: 0.74, 0.87; IRR women highest vs. lowest tertile = 0.90, 95% CI: 0.85, 0.95), but no consistent association between calcium and hip fracture risk was observed. The highest tertile of urbanization degree (city), compared to the lowest (rural), was related to a 23 and 24% increase in hip fracture risk in men and women, respectively. The association between magnesium and hip fracture did not explain the variation in hip fracture risk between city and rural areas. Magnesium in drinking water may have a protective role against hip fractures; however this association should be further investigated." - Norwegian Institute of Public Health
So for healthy hips and more, make sure to get your magnesium.
Note: No consistent association between calcium and hip fracture risk was observed.
P.S. My wife and I add this brand of sea salt to our drinking water. (No compensation for recommending this product.)