According to a new study published in the Lancet Respiratory Medicine, smoking five cigarettes a day is no less harmful as smoking an entire pack.
25,000 Americans aged between 17-93 were examined for this study and each of them were asked about how much they smoked. They also went through a spirometry exam which assessed their lung function by measuring how much air was exhaled and inhaled by them in a second. Then, the participants were tracked for 20 years and they went through one more spirometry test to assess changes in lung health.
You see, the lung function declines with age which is obvious but smoking just speeds up the process which increases the risk of chronic obstructive pulmonary disease and other respiratory conditions for smokers. And, essentially any amount of smoking can kick-start this effect.
It was found that those who smoked in the past and current smokers had poorer lung function than those who had never smoked. And there was a huge difference between the lungs of light smokers and heavy smokers.
Having less than five cigarettes per day caused almost the same lung damage as smoking 30 or more cigarettes per day. This also means that a light smoker is going to lose just about the same amount of lung function in a year as a heavy smoker would.
So in conclusion, there is no such thing as best amount of smoking. Any amount of smoking is extremely harmful and damaging so the best thing to do here, is to avoid smoking all together.