If you're obese (with a Body Mass Index of 30 to 35), the chance of returning to a normal weight are slim. According to a study published in the American Journal of Public Health, there's a one in 124 chance that obese women will shed the excess weight each year – and only a one in 210 chance for men.
Researchers at King's College London studied UK health records and found that those who are severely obese are even less likely to return to a healthy BMI. For women with morbid obesity (BMI 40 to 45), the chance of losing weight fell to one in 677 and one in 1,290 for men.
Researchers warn that current strategies for helping obese patients are failing and say "wider-reaching public health policies" are needed to prevent people gaining weight in the first place.
Lead researcher Dr Alison Fildes said: "Treatment needs to focus on stopping people gaining more weight and maintaining even small levels of weight loss.
"Current strategies that focus on cutting calories and boosting physical activity aren't working for most patients to achieve weight loss and maintain that.
"The greatest opportunity for fighting the obesity epidemic might be in public health policies to prevent it in the first place at a population level."
Weighing up the figures
Researchers looked at the weight of 278,982 men and women between 2004 and 2014 using UK health records. Those who had lost weight through surgery were not included.
Over the study period, 1,283 men and 2,245 women reached their goal of a normal body weight. Dr Fildes said the chance of losing 5% of body weight were more encouraging - one in 12 men and one in 10 women managed this over a year, although most had piled the weight back on within five years.
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