The majority of adults living with obesity who attempt to lose weight are unsuccessful, a new study suggests.
Only around a quarter of people who had attempted to lose weight managed to lose a significant amount last year.
The new study – being presented at the European Congress on Obesity (ECO) in the Netherlands (4-7) May – examines data on adults from the UK, France, Germany, Italy and Spain.
Lead researcher Dr Marc Evans from University Hospital Cardiff and his team analysed information on 1,850 individuals with obesity with an average age of 53, divided almost evenly between men and women, with pregnant women excluded.
Of these, some 79% said they had attempted to lose weight in the past year.
The most common weight loss methods were calorie-controlled or restricted diets (72%), exercise programmes or courses (22%) and pharmaceutical treatments (12%).
However, three-quarters did not achieve a "clinically meaningful weight loss", which is defined as at least 5% of their body weight.
Those who opted for surgery (which is a major operation and should, in most cases, only be considered after trying to lose weight through a healthy diet and exercise) were most likely to have lost weight, with half losing at least the 5%.
Some 32% who used digital health applications lost weight and three in 10 who used a weight loss service saw results.
Nearly a third (30%) of those who used medication or took up exercise lost a clinically meaningful amount of weight.
Only 28% of people who embarked on a calorie-controlled or restricted diet lost a significant amount of weight.
But the researchers also discovered that those who had tried more than one method of weight loss – for example, exercise and a calorie-controlled diet together – were more likely to succeed.
Only 22% of those who attempted one weight loss strategy had shed a significant proportion compared to 33% who used a combination of weight loss tools.
“Our survey results indicate that while the majority of adults with obesity are actively trying to reduce their weight, using a variety of strategies, most are unsuccessful,” says Dr Evans.
“This underscores the need for increased support and solutions for weight management.
"And while obesity’s impact on health is well-known, our finding that a sizeable proportion of adults with obesity appear at elevated risk of hospitalisation or surgery due to multiple underlying illnesses, undoubtedly adds a sense of urgency to tackling Europe’s growing obesity epidemic.”
This comes as a separate study published at the conference unearthed that the impact of losing or gaining weight on serious health problems among obese people depends on their starting body mass index (BMI).
The study, led by Professor Kamlesh Khunti from the Diabetes Research Centre at the University of Leicester, examined data on 422,642 adults in the UK with obesity between 2001 and 2010.
The researchers compared how the risk of developing 13 obesity-related complications – including sleep apnoea, high blood pressure, dangerous blood clots, irregular heart rhythm, heart failure, asthma, chronic kidney disease, polycystic ovary syndrome (PCOS) and depression – was affected by their weight change pattern during a four-year period after their first BMI measurement.
During an average seven-year follow-up, the researchers found that at any level of initial BMI, there was both a benefit to weight loss and a harmful effect from weight gain – this applied to all 13 health complications.
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That said, the trends still differed by the initial BMI. For heart attack, irregular heart rhythm and heart failure, those with the highest initial BMI (50) got the greatest benefit from weight loss.
But for other conditions, losing weight seemed to give more benefit for people with a BMI of 30.
For example, people with a BMI of 30 who lost around a fifth of their total body weight had a 56% lower relative risk of developing type 2 diabetes, but the risk only fell by 39% for those with a BMI of 50.
“If intentional weight loss in people with obesity with a lower BMI of around 30 is particularly beneficial to health, and weight gain potentially harmful, we should focus on treating obesity earlier in the course of the disease,” concludes Professor Khunti.
Additional reporting PA.