Editor's Note: (Vital Signs is a monthly program bringing viewers health stories from around the world)
(CNN) Globally, more than 1 billion people are estimated to smoke tobacco. Collectively, they smoked 5.8 trillion cigarettes in 2014, according to the 2015 Tobacco Atlas.
Whilst the number of smokers has fallen rapidly in countries such as the UK, Brazil and Australia, this decrease has been countered by the rapid rise of people now consuming tobacco in China where numbers are higher than the top 29 countries combined.
But kicking the habit is no easy feat. According to the World Lung Foundation, 85% of smokers in the USA say they have tried to quit at least once.
For World No Tobacco Day, May 31, we wanted to know the reasons why you quit smoking -- so we asked ex-smokers to complete this sentence: "I quit smoking because..."
Using the hashtag #WhyIQuit you responded in droves with a diverse range of reasons to stop smoking. So, in your own words, here are 10 reasons to quit.
Smoking tobacco has a multitude of effects on human health with its biggest impact on the heart and lungs.
This impact is wide-ranging, from increased risk of lung cancer and heart attacks to aging of the skin, psoriasis, acne and a decreased sense of smell and taste -- to name a few.
UK-based charity Action on Smoking and Health (ASH) highlights a range of benefits from quitting smoking with some -- such as your pulse returning to normal rates -- starting as early as 20 minutes after your last cigarette.
According to the World Lung Foundation, quitting before the age of 40 reduces a smoker's chance of death from tobacco-related illness by 90%.
A 2005 study among British doctors concluded that people who stop smoking at ages 60, 50, 40, or 30 gain approximately 3, 6, 9, or 10 years of life expectancy, respectively.
Increased tobacco taxation and the resulting rise in the cost of tobacco products is considered among the most effective tobacco control measures to date with less people continuing, or taking up smoking, as a result.