Chronic stress, use of stimulants, (coffee, energy drinks, sugar, smoking, drugs) and poor eating habits will burn out adrenal glands and cause osteopenia and osteoporosis meaning bone loss.
Bone loss can come in part from overexercising, without eating enough protein.
Bone loss can also come from not exercising.
Bones are mainly protein. Proteins breakdown and rebuild. This is normal. Adrenaline breaks them down. Protein rebuilds.
Exercise is necessary for strong bones. However, when you exercise there must be time in between exercising for your body to heal and rebuild before exercising again. If not, bone loss occurs.
If you eat protein by itself or if you eat too much protein, adrenaline is secreted and bone loss can occur.
Eating an unbalanced diet causes bone loss. It is imperative that there is a balance between protein and carbohydrates to keep the adrenaline levels balanced.