Here a few abstracts that indicate the association between insulin resistance, high levels of insulin (hyperinsulinemia), hair growth (hirsutism), and elevated levels of male hormones (hyperandrogenemia). There is considerable overlap among these entities with so-called Polycystic Ovarian Syndrome (a condition most commonly affecting overweight women which is characterized by hirsutism, mentrual disturbance, and varying degrees of infertility).
Role of hyperinsulinemia in the pathogenesis of the polycystic ovary syndrome, and its clinical implications
Insulin-lowering drugs in polycystic ovary syndrome
Insulin resistance in polycystic ovary syndrome.
Obesity and the polycystic ovary syndrome
Insulin resistance, polycystic ovary syndrome and metformin
With respect to fat as a source of estrogen - it is. In fact, that may explain, in part, the association between obesity and breast cancer/uterus cancer.
It seems, though, that in many obese women, the estrogen effect is offset by the high male hormones that have resulted from the insulin resistance/high levels of insulin. Also, the uninterrupted high levels of estrogen which result from obesity(as opposed to the cyclically high levels in “normal” women), promote (through endocrine feedback) the production of even more male hormone.
Finally, in women, obesity and high levels of insulin both lead to more male hormone being “free” and “unbound” and thus more able to have a biological effect, including its ability to promote male type hair growth (i.e. usually, most of the male hormone in women is effectively inactivated by being bound to various proteins in the bloodstream.
It’s a confusing, but fascinating, set of processes.