Lp(a) concentrations were similar in women with obesity and high and normal concentrations of insulin (19.9 mg/dl vs. 18.6 mg/dl), but men with obesity and hyperinsulinaemia had significantly lower Lp(a) levels than did men with obesity and normo-insulinaemia (7.9 mg/dl vs. 29.4 mg/dl). Here, INS is linked to obesity due to melanocortin 4 receptor deficiency.