How common is nicotine addiction?
Around 12.5 million adults in the UK smoke cigarettes. That's 20 in every 100 people aged 16 and over.
Many smokers are young. Among secondary school children aged 11 to 15, 12 in every 100 girls and 9 in every 100 boys are regular smokers.
The good news is that a smaller percentage of the population smokes now than 30 years ago. In 1974, for example, nearly one-half of the people in the UK smoked.
Also, people aren't smoking as many cigarettes as they used to. There are fewer heavy smokers (people who smoke more than 24 cigarettes a day) and more light smokers (those who smoke fewer than 15 cigarettes a day).
But this downwards trend in smoking has slowed. The proportion of people smoking has only gone down a little since about 1994.
Here are some figures about smoking.
More men than women smoke. But the gap has closed in the last 60 years.
In 1948, about 80 in every 100 men and 40 in every 100 women smoked.
In 1974, 51 in every 100 men and 41 in every 100 women smoked.
In 2006, 23 in every 100 men and 21 in every 100 women smoked.
Smoking is the biggest cause of death and illness in the UK.
More than 120,000 people in the UK die each year from a disease that's caused by smoking.
One in five deaths in the UK is due to smoking.
If you smoke regularly, you have a 50-50 chance of dying from a disease that's caused by smoking.
The most common diseases caused by smoking are lung cancer, heart disease, and stroke. Many other cancers are also linked to smoking.