Ex-smokers can expect to gain an average of 9 to 11lbs within 12 months of quitting, with most of the weight gain occuring within the first three months.
According to a new study by British and French researchers published by the British Medical Journal, the average weight gain was 2.4lbs at one month, 5lbs at two months, 6.4lbs at three months, 9.2lbs at six months, and 10.3 kg at 12 months.
The calculations were based on 62 studies assessing weight change among successful quitters conducted between 1989 and 2011 in the United States, Europe, Australia and east Asia, AFP reports.
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The Guardian says the study shows smokers gain much more weight than the 6.3lbs usually quoted in health advice leaflets.
However, Nine News says the study also found 16 to 21 percent of ex-smokers actually lost weight, while 35 to 38 per cent gained less than 11 percent. Another 29 to 34 per cent gained 11 to 22lbs, and 13 to 14 per cent put on more than 22lbs.
A note from the British Medical Journal posted by Eureka Alert argues that although these figures are higher than previously thought, the health benefits of quitting far outweigh the weight gain.
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