Why you might actually be healthier if you put on weight

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Is it healthy to store a bit of weight? A study of tens of thousands of people suggests it is.

New research, presented to the annual meeting of the European Association for the Study of Diabetes in Vienna, found that people who had a body mass index (BMI) in the overweight category, and in the lower end of the obese category, were less likely to die than those in the healthy weight range.

It also found that those with a BMI in the middle and lower end of the normal weight range had the highest risk of mortality, as did individuals with a BMI in the underweight range. A healthy BMI is between 18.5 and 24.9.

Dr Sigrid Bjerge Gribsholt, from Aarhus University Hospital, said: “Both underweight and obesity are major global health challenges.

“There are conflicting findings about the BMI range linked to lowest mortality. It was once thought to be 20 to 25 but it may be shifting upward over time owing to medical advances and improvements in general health.”

Those who were underweight were three times more likely to have died
Those who were underweight were three times more likely to have died (Getty/iStock)

The researchers examined the relationship between BMI and death in more than 85,000 individuals in Denmark, 80 per cent of whom were female.

During a follow-up, 8 per cent of the participants had died, with those in the underweight category nearly three times more likely to have died than individuals with a BMI at the upper end of the health range. Those who were severely obese were twice as likely to die compared with the reference population.

Those who were at the lower end of the healthy weight range were twice as likely to have died, and those in the middle of the healthy weight range were 27 per cent more likely to have died.

Those with a BMI in the overweight range or at the lower end of the obese range were no more likely to have died than those in the reference population. But those who were significantly obese were 23 per cent more likely to have died.

Dr Gribsholt said: “One possible reason for the results is reverse causation: some people may lose weight because of an underlying illness.

“In those cases, it is the illness, not the low weight itself, that increases the risk of death, which can make it look like having a higher BMI is protective.

“Still, in line with earlier research, we found that people who are in the underweight range face a much higher risk of death.”

In the UK, the popularity of weight loss jabs continues to grow, with an estimated 1.5 million people using the injections, like Mounjaro or Wegovy, in an attempt to shed fat. The medication, which is injected, mimics a hormone your body releases after eating called GLP-1, which slows down the body’s digestion, lowers the appetite, and makes you feel full.

The jabs can be obtained through the NHS, but a GP must first refer you to a specialist weight management service. The vast majority of people using the jabs are paying privately, and nearly half of its users are obtaining the medication without a prescription.