I have been interested in smoking and rheumatic diseases for quite a while. Some of my blog posts are only in German as I use these texts also for real life patient education and information. About 10 years ago we developed a leaflet for patient to promote smoking cessation. Some did und some had problems with weight gain. As weight gain is a constant problem in a setting, where steroids are used, I’m very concerned about this issue.
Today I stumbled upon a study by L. Biedermann and colleagues: “Smoking cessation induces profound changes in the composition of the intestinal microbiota in humans.” They observed “profound shifts in the microbial composition after smoking cessation” and “an increase in microbial diversity.” They concluded: “These results indicate that smoking is an environmental factor modulating the composition of human gut microbiota. The observed changes after smoking cessation revealed to be similar to the previously reported differences in obese compared to lean humans and mice respectively, suggesting a potential pathogenetic link between weight gain and smoking cessation.”
I think the paper is important not only as there is an explanation for the weight gain and a rehabilitation of people, who didn’t gain weight because of consuming more sweets, but it might also lead to therapies that actively change the composition of the intestinal microbiota. If this would help people, who quit smoking, maybe it could also help obese people.
Abstract on Pubmed: http://www.ncbi.nlm.nih.gov/pubmed/23516617
Full article: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3597605/
Besides the above mentioned changes in the intestinal microbiota there are other mechanism involved as well, which will lead to weight gain. Nicotine suppresses appetite. Food might act as a replacement for smoking. Sweets and nicotine act on dopaminergic receptors in the brain, which make us feel good.