How Many Years of Smoking Causes Cancer?

Smoking cigarettes increases your risk of cancer. Quitting smoking is your best choice for lowering your risk.

We know that smoking cigarettes increases your risk of cancer. But how many years of smoking does it take to develop cancer?

In short, any amount of smoking — for any length of years, no matter how much you smoke — seems to increase your risk of developing cancer, especially lung cancer. Smoking can also cause other health issues, such as cardiovascular problems.

Although smoking more cigarettes increases your risk of developing cancer, it’s difficult to quantify how long you have to smoke to get cancer. Quitting smoking cigarettes can help lower your risk of health issues.

There’s very little data on how long you have to smoke to get cancer. But the longer and the more you smoke, the higher your chances of developing cancer. When you quit smoking, your risk of developing cardiovascular diseases and cancers gradually decreases.

When it comes to smoking, your risk of developing cancer increases not just based on how long you smoke but on how much you smoke. The more cigarettes you smoke per day, the higher your chances of developing cancer.

According to the Centers for Disease Control and Prevention (CDC), up to 9 out of 10 fatal lung cancer cases in the United States are caused by smoking cigarettes (or exposure to secondhand smoke). Cancer Research UK estimates that 7 in 10 lung cancer cases in the United Kingdom are caused by cigarettes.

How many cigarettes do you need to smoke a day to get cancer?

There’s no “safe” number of cigarettes you can smoke per day. Any number of cigarettes can increase your risk of developing cancer.

But the more you smoke, the more likely you are to get cancer. A 2021 study looked at 229,028 Australian participants to estimate how likely people are to develop cancer by age 80.

In the study, only 1% of people who’d never smoked developed lung cancer by age 80. The study found that the risk of developing lung cancer increases to 14% if you smoke cigarettes.

If you smoke one to five cigarettes per day, your risk is around 7.7%, and if you smoke more than 35 cigarettes per day, you’ll have a 26.4% chance of developing lung cancer by age 80.

Bear in mind that you don’t need to smoke in order to develop smoking-related cancers. Secondhand smoke also increases your risk of developing lung cancer.