A new government report warns that one single inhalation from a cigarette can trigger a heart attack and can cause damage to nearly every organ in the body.
"That one puff on that cigarette could be the one that causes your heart attack," said U.S. Surgeon General Regina Benjamin.
There are 7,000 chemicals released in just one puff and the tobacco smoke begins poisoning the body immediately.
Even social smoking or breathing in second-hand smoke could be enough to trigger a heart attack.
Benjamin said kicking the habit will cause the body to start healing immediately.
"It's never too late to quit but the sooner you quit the better" she said. Even if you're 70, 80 years old and you're a smoker, there's still benefit from quitting."
An estimated 443,000 Americans die from tobacco-caused illnesses every year.