Smoking does burn up some calories and may serve to suppress appetite but the long-term cost of these changes is far too great. Exercise will also burn up calories and you will feel better for it. You are less likely to exercise if you smoke and you start to cough whenever you try to exert yourself. The lack of physical fitness that often accompanies the smoking habit would seem to be less than helpful in one's efforts to create a positive self-image.While older women who smoke may on average be thinner they are also much more likely to have lung cancer and die prematurely. Weight is only ever one part of the image equation and while these girls are young they do not appreciate that smoking can cause other long-term cosmetic changes such as premature aging or increased wrinkling and greying of the skin. They do not consider that they will have to give up smoking later on in life if they want to have a baby. Risking one's own health is one thing but the health of their family should take precedence over any selfish concerns they have about their weight. They may think that they can quit at any time without appreciating that, for both physiological and sociological reasons, women generally find it harder to give up smoking than men. They may also not know that, on average, women are more at risk from smoking related diseases than men.