“…Notes: Recent genetic studies have challenged some long-assumed risk factors for OP/OF. Mendelian randomization analyses identified BMD [ 413 , 635 , 636 , 637 ], serum estradiol concentrations (in men) [ 638 ] and cigarette smoking [ 639 ] as causal risk factors for OP/OFs, whereas genetic predisposition to lower levels of vitamin D and milk calcium intake [ 635 , 636 , 639 , 640 ], serum testosterone [ 638 ] and inflammation markers [ 641 , 642 ], as well as early menopause; late puberty, chronic (including CVD, DM and IBD) [ 413 , 414 , 643 ] and neuropsychiatric diseases (Alzheimer’s disease, schizophrenia and bipolar disorder) [ 644 ], alcohol consumption [ 645 ] and alcohol dependence [ 639 ] did not show causal effects on BMD and fracture risk. The genetic studies overcome many limitations of the previous observational studies but also contain potential bias; “the Mendelian randomization study design cannot be used to assess whether complications or treatment of those diseases influence fracture risk” [ 636 ].…”