This video will make you want to quit smoking cigarettes immediately

A video posted by a non-profit medical group shows the grim effect of smoking just 20 cigarettes

It's well known that smoking takes years off your life. Researchers at the University of Bristol previously conducted a study into the exact amount of a time each cigarette will steal from you.

Based on data held by the Office for National Statistics, the researchers found that the difference in life expectancy of smokers and non-smokers was six and a half years in total. The group explained their methodology.

We calculated that if a man smokes the average number of cigarettes a year (5772) from the median starting age of 17 until his death at the age of 71 he will consume a total of 311,688 cigarettes in his lifetime.

From this data they calculated that each cigarette removes 11 minutes from a man's life. They also published a table of opportunities lost by smoking:

• One cigarette (11 minutes) = Telephone call to friend; read of newspaper; brisk walk; or fairly frantic sexual intercourse.

• Pack of 20 cigarettes (3 hours 40 minutes) = Long film (for example, Titanic); two football matches; one shopping trip; Eurostar journey from London to Paris, including visit to cafe; running in London marathon; or tantric sex.

• Carton of 200 cigarettes (1.5 days) = Visit to friends or family; one very serious shopping trip; Wagner opera; flying round the world; or romantic night away.

The findings were originally published in the British Medical Journal, and can be read for free in the US National Institute of Health's National Library of Medicine.

A video posted on the Instagram of non-profit group 'MEDspiration' shows an experiment into the amount of tar that builds up inside your lungs. In the video, a cigarette is 'smoked' by a machine hooked up to a pair of lungs. The lungs creepily inflate, and after 20 cigarettes they are cut open to reveal the grim after-effects of smoking. It has already been viewed over 37,000 in the three weeks since it has been published.

See the full video from MEDspiration:

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