More than 7 million people worldwide die from smoking-related deaths every year, according to the World Health Organisation, or roughly one every five seconds. Lung cancer is the third most common cancer worldwide, according to the World Cancer Research Fund International. Smoking is the main cause of lung cancer: it is responsible for over 90 per cent of cases in men and over 80 per cent in women. Smoking can also wreak havoc from our heads – accelerating hair loss, balding and greying, says the American Academy of Dermatology – to our fingers and toes, where it can encourage fungal nail infections, the News Medical portal reports. The use of e-cigarettes increases the risk of heart attacks by 34 per cent, coronary heart disease by 25 per cent and depression by 55 per cent, according to recent research by the University of Kansas School of Medicine-Wichita in the United States. Researchers at the University of Leeds in the UK found that patients with the most dangerous form of skin cancer – melanoma – with a history of smoking are 40 per cent less likely to survive their disease than those who have not smoked in the decade after their diagnosis. Smoking impairs sex. It has an effect on blood vessels that makes it harder for men to have an erection and decreases lubrication in women, says the International Society for Sexual Medicine. How to quit smoking: five tips from a smoker who stopped after 35 years Despite its well documented and real health risks, large numbers of people are addicted to nicotine, whether through smoking or vaping. China has more than 300 million smokers, according to the World Health Organisation (WHO), and accounts for one in every three cigarettes smoked globally. Around 640,000 people in Hong Kong smoke daily, according to the city’s government. More than 6,000 Hongkongers die of tobacco-related causes annually, says the Hong Kong Council on Smoking and Health. In addition, around 1,300 non-smokers die in the city every year from second-hand smoke. The Annals of Internal Medicine says that one in 20 adults in the United States – more than 10 million people – use e-cigarettes. A survey last year of middle and high school pupils by the US Food and Drug Administration found that 3.6 million had vaped in the preceding 30 days. Vaping among US high school students grew 78 per cent from 2017 to 2018. If they know the risks, why are they still smoking? Research published in the BMJ Open medical journal suggests that for many smokers it may take up to 30 attempts before they can quit successfully.