History of tobacco, vitamin D and women.

Tobacco usage kills more than 8 million people a year. Approximately 7 million of those deaths are the result of direct tobacco use, while approximately 1.2 million are the result of non-smokers being exposed to second-hand smoke. About 200 million of the world's one billion smokers are women and usage among women is increasing in some countries. Nicotine from smoking tobacco, specifically its metabolite cotinine, has negative effects on human health causing lung cancer, COPD and non-respiratory problems. Over a billion people worldwide are Vitamin D deficient or insufficient, which is prevalent across all age-groups, geographic regions, and sunlight. With the discovery of Vitamin D in 1919, a new chapter in the prevention of rickets was introduced opening the door to its therapeutic properties for other diseases. Since 1919, there have been many clinical and epidemiolocal studies performed globally on the effect of the vitamin on prevention of other diseases, including but not limited to, cancer, autoimmune disorders, cardiovascular diseases, and osteoporosis. Exposure to environmental tobacco smoke has been associated with reduced levels of Vitamin D in the blood stream and sinus tissues. Manavi et al. (2015) demonstrated that among three smoking categories (heavy, light, non-smokers), black female heavy smokers have lower vitamin D (13.374 ng/ml), than Hispanic (19.213 ng/ml) or white (24.929 ng/ml) females correlating to higher levels of cotinine. Therefore, blood serum concentrations of cotinine contribute to decreased Vitamin D concentrations in addition to other factors such as gender and ethnicity. Further information is provided in the text.