i would have to say smoking because it permanently damages your lungs and heart which will lead to early death, although obesity is bad and can also lead to early death, you can lose weight and eat healthy which will reduce the risks of early death
smoking is worst, everyday in the United States about 1,200 people die everyday because of smoking. Yes smoking is legal but that does not mean is good for us.
Secondhand smoking means the passive smoking and passive smoking is worse even than smoking cigarettes.
Cigarette smoking lowers HDL cholesterol, as does malnutrition and obesity
One reason is sedentary life style. Other being stressful life style. Then there is obesity. Then you have the smoking and tobacco use. Next is untreated or not so well treated hypertension.
Considering both sugar and smoking are completely different topics this is hard to answer. Smoking is worse for your lungs, sugar for your overall weight.
there is no difference
Smoking is bad regardless of when you start smoking. And the longer you smoke the worse it is for you health.
Snorting cocaine is significantly worse than smoking marijuana. If you do your research smoking marijuana over the age of 25 causes very little harm.
Smoking, Obesity and Alcohol are the big ones.