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Smoking, tobacco and cancer

Is vaping harmful?

  • Research so far shows that legal e-cigarettes are far less harmful than smoking.

  • For people who smoke, legal e-cigarettes are an option to help them stop.

  • E-cigarettes are not risk-free. We don't yet know their long-term effects, so children and people who have never smoked shouldn't use them.

You may have heard different things in the media about the side effects of vaping. This page gives an overview of what we know so far about how vaping can affect your health. Our information relates to legal e-cigarettes – ones that are registered with the UK Medicines and Healthcare products Regulatory Authority (MHRA). Always use legal e-cigarettes from a reputable retailer.

What are e-cigarettes?

Electronic cigarettes are also known as e-cigarettes or vapes. They heat a liquid that becomes a vapour people can breathe in. They usually contain nicotine, which is the addictive chemical in cigarettes. E-cigarettes do not contain tobacco, which is the harmful part of cigarettes that causes cancer.

Does vaping have side effects?

Lots of people want to know about the health effects of e-cigarettes. They’re still a relatively new product, so it’s too soon to know for sure. Many studies show that vaping is far less harmful than smoking. This is because e-cigarettes don’t contain cancer-causing tobacco, and most of the toxic chemicals found in cigarettes are not in e-cigarettes.

Some potentially harmful chemicals have been found in e-cigarettes. But levels are usually low and generally far lower than in tobacco cigarettes.

There is no good evidence that vaping causes cancer.

But e-cigarettes are not risk-free. They can cause side effects such as throat and mouth irritation, headache, cough and feeling sick. These side effects tend to reduce over time with continued use. We don’t know yet what effects they might have in the long term.

E-cigarettes should only be used to help you stop smoking, or to stop you going back to tobacco. Most e-cigarettes contain nicotine, which is addictive. If you have never smoked, you shouldn’t use e-cigarettes.

Read more about the research into e-cigarettes so far and what we still need to find out.

What are the benefits of switching from smoking to vaping?

Smoking causes at least 16 different types of cancer so stopping smoking completely is the best thing you can do for your health. E-cigarettes can help people stop smoking and are an effective stop smoking tool. There’s no safe level of smoking, so it is important to stop tobacco-use completely.

Find out more about the tools and support available to help you stop smoking.

Because vaping is far less harmful than smoking, your health could benefit from switching from smoking to vaping. And you will reduce your risk of getting cancer. Switching from cigarettes to e-cigarettes could also save you a lot of money. Some people spend more than others but in general smoking costs more than vaping.

Is passive vaping harmful?

There is no good evidence that second-hand vapour from e-cigarettes is harmful. As vaping is still relatively new, we can’t be sure there aren’t any long-term effects to people who breathe in someone else’s vapour. But this is unlikely to be harmful.

Passive vaping is not the same as passive smoking. This is because e-cigarettes do not contain tobacco.

Does nicotine cause cancer?

Nicotine is the chemical that makes cigarettes addictive. But it is not responsible for the harmful effects of smoking, and nicotine does not cause cancer. People have safely used nicotine replacement therapy (NRT) to stop smoking for many years. Nicotine replacement therapy is prescribed by doctors or is available from pharmacies.

Find out more

You can read about:

Find out how to stop smoking

Article on e-cigarettes: what we know and what we don't know

The myth of e-cigarettes and popcorn lung

Last reviewed: 17 Oct 2025

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