Osteoporosis is a condition that makes bones more apex

Fragile

Osteoporosis is the reduction of the bone density of the bones of the body. This makes bones more susceptible to fracture, and there are a number of factors enhancing the chances of the development of osteoporosis in an individual. These factors include lack of calcium and vitamin D in the diet, genetics, lack of exercise, cigarette smoking, excessive drinking and many more.

Magnesium! this is found if caves usually