Switching to low-yieldcigarettes, those that yield less nicotine, tar, and carbon monoxide than regular cigarettes when tested on a standard machine, does not, in general, reduce the incidence of heart attack
This result is surprising, since nicotine and carbon monoxide have been implicated as contributing to heart disease
People who switch from high-yield to low-yield cigarettes often compensate by increasing the number and depth of puffs in order to maintain their accustomed nicotine levels.