These risk factors could potentially function as either mediators or confounders, given that epidemiological associations have been described between both scoliosis and BMD and BMI,[6, 7, 51, 52, 53, 54, 55, 56] body fat mass,[9, 53, 54, 55, 56, 57] and 25OHD.[13, 58, 59] Regarding BMI and body fat mass, the hormone leptin, which is secreted by fat cells, has a negative impact on bone mass[60] and a positive impact on the muscle mass,[9] suggesting that being underweight could impair postural balance, favoring a risk of developing scoliosis. This evidence concerns the gene LEP and scoliosis.