Smoking is indeed related to two aspects of male reproductive behavior: erectile dysfunction and lack of libido. The two aspects are completely different; though in many cases, the psychological scars of having one will signal the onset of the other. Erectile dysfunction is a condition in which the penis is not erect enough, or fails to stay erect for long enough for a pleasurable sexual experience. This problem can be caused by a variety of reasons like cardiovascular disease, decreased levels of the male hormone testosterone, and the effect of some types of medication as well psychological anxiety of having sex. Smoking is also a causative factor because an erect penis relies heavily on an adequate blood flow to the organ. Smoking constricts and shrinks the size of many blood vessels in the body and this affects the penis with stark consequences. The male libido usually fades away naturally in time but this is accelerated if there is some kind of a psychological block against feeling desire or if the levels of the male hormone are low. Smoking also has a dulling effect on the senses and this could be a cause for the loss of interest in sex. However, it would be incorrect to implicate smoking as a sole cause for the problem, especially if your husband has not been tested for any other underlying problems. A decreased hormone count can also be a significant cause for a loss of libido.
You would have noticed that the psychological aspect plays a great role in the problems. This is something to consider and to talk to your husband about. You should try and gather whether your husband is feeling generally more disinterested in sex or whether there is something that is lacking in the sexual experience itself. Additionally, it is also important to figure out if there is any erectile dysfunction in your husband. You might also want to consider talking to a counselor about the problem.
However, while you do all this there is an interesting step you could take. This might involve a vacation to a place that is nice and sunny. The reason for this is that it is understood that melanocortin is an important and highly potent promoter of sexual desire in men and women. This hormone is actually responsible for stimulating the tanning of the skin indirectly from the action of Melanocyte Stimulating Hormone or MSH. When you spend some time in the sun, the body requisitions more MSH to produce melanocytes cells, these further secrete melanin to protect the body from damage. With more sun exposure, the more the MSH, and therefore the possible increased libido.
answered by G M