Here's a pretty large study (650 women with PCOS) that illustrates why taking care of your PCOS is not just about diet and exercise.
Smoking cigarettes may be very important in hormone function and PCOS. They found that women with PCOS who smoked, compared to women with PCOS who did not, had higher fasting blood lipids (cholesterol, triglycerides, and low-density lipoprotein) and lower prolactin levels. They also had higher adrenal responsiveness (meaning more cortisol secretion).
One of the reasons often given by women for not quitting smoking is that it helps keep weight down. But if you're doing unhealthy things to keep that weight down (restrictive dieting, smoking, diet pills, etc.), you may be making the problem you are trying to control, even worse.
Sometimes the initial weight gain that comes with quitting smoking keeps people from quitting. But if you hang in there, and keep up the other healthy behaviors you have been working on, that weight will eventually come off. It's a type of weight gain, in my opinion, that is well worth it, for the long-term gains you earn.
It's a tough one, I know…nicotine is the second most addictive substance (behind heroin) known to man…but if you can conquer the butts…you can do just about anything that comes along afterward that you decide to put your mind to.
Glintborg D, Mumm H, Hougaard DM, Ravn P, Andersen M. Smoking is associated with increased adrenal responsiveness, decreased prolactin levels and a more adverse lipid profile in 650 white patients with polycystic ovary syndrome. Gynecol Endocrinol. 2011 Jul 20. [Epub ahead of print]