The amount of calcium in your diet. A diet low in calcium contributes to diminished bone density, early bone loss and an increased risk of fractures.Physical activity. People who are physically inactive have a higher risk of osteoporosis than do their more-active counterparts.Tobacco and alcohol use. Research suggests that tobacco use contributes to weak bones. Similarly, regularly having more than one alcoholic drink a day for women or two alcoholic drinks a day for men may increase the risk of osteoporosis.Sex. You’re at greater risk of osteoporosis if you’re a woman, because women have less bone tissue than do men.Size. You’re at risk if you are extremely thin (with a body mass index of 19 or less) or have a small body frame because you might have less bone mass to draw from as you age.Age. Your bones become thinner and weaker as you age.Race and family history. You’re at greatest risk of osteoporosis if you’re white or of Asian descent. In addition, having a parent or sibling who has osteoporosis puts you at greater risk — especially if you also have a family history of fractures.Hormone levels. Too much thyroid hormone can cause bone loss. In women, bone loss increases dramatically at menopause due to dropping estrogen levels. Prolonged absence of menstruation (amenorrhea) before menopause also increases the risk of osteoporosis. In men, low testosterone levels can cause a loss of bone mass.Eating disorders and other conditions. Severely restricting food intake and being underweight weakens bone in both men and women. In addition, weight-loss surgery and conditions such as celiac disease can affect your body’s ability to absorb calcium.Certain medications. Long-term use of corticosteroid medications, such as prednisone, cortisone, prednisolone and dexamethasone, is damaging to bone. Other drugs that might increase the risk of osteoporosis include aromatase inhibitors to treat breast cancer, selective serotonin reuptake inhibitors, methotrexate, some anti-seizure medications, such as phenytoin (Dilantin) and phenobarbital, and proton pump inhibitors.
https://www.mayoclinic.org/healthy-lifestyle/adult-health/in-depth/bone-health/art-20045060