I know it is a very hard decision but I myself have never been in a situation like that. My response would be to say no because it is not healthy and in my religion your bodies should be a living sacrifice and acceptable to God. Smoking can lead to cancer, heart disease, stroke, lung diseases, diabetes, and chronic obstructive pulmonary disease.
Followers of Judaism would say, smoking is not forbidden but it is not healthy and followed of Judaism are expected to keep themselves healthy and free from diseases.
Followers of Sikhism would say, one of our commands is about not smoking, drinking alcohol and doing drugs.
Great advice showing an understanding of a range of religions and beliefs.