Can you achieve a healthy weight if you're obese?

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“Obese men have just a '1 in 210' chance of attaining a healthy body weight”

- The Independent, 17 July 2015

This study of changes in weight was also covered in the Daily Mail, BBC News, ITV News and others.

Researchers from King’s College London used data from UK general practices to study 278,982 people who had their body mass index (BMI) measured more than once between 2004 and 2014.

The authors described it as “one of the largest studies yet reported on body weight changes in the general population”. They classified people as normal weight, overweight, obese, severely obese, morbidly obese or super obese, based on their BMI. People who had weight loss surgery were not included.

The results showed that the annual probability of attaining normal weight was 1 in 210 for obese men and 1 in 124 for obese women, increasing to 1 in 1290 for men and 1 in 677 for women with morbid obesity.

The annual probability of achieving a 5 per cent weight reduction was significantly more likely – ranging from 1 in 12 for obese men and 1 in 10 for obese women, to 1 in 8 for men and 1 in 7 for women with morbid obesity. But many people who lost weight did put it back on later. The study authors called for more effective systems to help people with weight loss, as well as a focus on preventing obesity.

The results of this study shouldn’t be taken to mean that if you are obese you should give up trying to lose weight, but it does remind us how difficult it can be to lose excess weight once it’s been gained

Victoria Taylor

One of the major limitations of the study was that it did not have information on whether people were actually trying to lose weight, although the authors said “previous studies have reported that the majority of obese individuals would like to lose weight and that a large proportion is actively attempting to reduce their weight”.

Some of the news coverage failed to make it clear that the odds of returning to normal weight were based on an annual probability, not your total chance in a lifetime. In some obese people it may take longer than a year to return to a normal weight.

Victoria Taylor, our Senior Dietitian, said: “The results of this study shouldn’t be taken to mean that if you are obese you should give up trying to lose weight, but it does remind us how difficult it can be to lose excess weight once it’s been gained.

“While a quick fix can seem like the way to solve the problem, a steady weight loss may be a more achievable approach and even a modest reduction in BMI can bring important health benefits.

“Sticking with changes in the long term and changing food habits of a lifetime can be hard to do, especially if you have a lot of weight to lose. But remember, even if the numbers on the scales don’t change, eating healthily and being physically active will still be benefiting your heart health.”

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