Past obesity can have lasting effects on mental health, study finds

Previously obese people who slim down to a healthy weight still have a heightened risk of dying early as they are more likely to struggle with their mental health, research suggests.

The study tests the “weight scarring” hypothesis, which theorises that past obesity can leave a negative legacy on a person’s current psychological wellbeing. That can bring about meaningful health consequences such as depression and anxiety.

It found a history of obesity increased the risk of early death by about a third and concluded that obesity can have lasting effects on mental health regardless of a person’s current weight.

The analysis, presented at the European Congress on Obesity in Dublin, shows past obesity was associated with greater depressive symptoms. These depressive symptoms includes hopelessness, anxiety, loneliness, and pessimism.

Dr I Gusti Ngurah Edi Putra of the University of Liverpool, who led the study, said: “Some previous studies indicated that some people who lost weight and were no longer classed as having obesity still feared being stigmatised due to having previously had obesity.

“This led us to hypothesise that past obesity may have long-term psychological impacts that persist even after individuals are no longer classified as having obesity.

“We have tested this novel ‘weight scarring’ hypothesis and are presenting our preliminary findings at ECO.”

Researchers looked at information on past and current weight, height, symptoms of depression and other psychological wellbeing indicators, and mortality from a large dataset of people from the US.

They used data from 29,047 individuals from the National Health and Nutrition Examination Survey (NHANES), and 11,998 individuals from the Health and Retirement Study (HRS).

A history of obesity increased the risk of early death by about 30% (31% in NHANES and 34% in HRS), independent of current weight status.

The analysis, funded by the UK Economic and Social Research Council, called for people who have lived with obesity to receive continued mental and psychological support, even after experiencing weight loss. The study also carried the assumption that weight loss should ameliorate the psychological burdens of obesity.

Putra added: “Our findings suggest that obesity may be psychologically ‘scarring’ and that these psychological ‘scars’ may increase the risk of an early death.

“Ensuring people with obesity receive psychological support, even after experiencing weight loss, may reduce the risk of subsequent ill health.

“It is important to note that these preliminary findings, which are yet to be published, are based on observational data and so we cannot establish causation, only associations. Further research confirming our findings is now needed.”

Previous studies have shown that people with obesity can experience “weight-shame” and stigmatisation by healthcare professionals including doctors and nurses, leading to feelings of anxiety and depression.

A study from last year conducted by University College London looked at 25 previous studies about “weight stigma”, undertaken in different countries, involving 3,554 health professionals.

They found extensive evidence of strong weight bias, including the belief that their patients are lazy, lack self-control, overindulge, are hostile, dishonest, have poor hygiene and do not follow guidance, among a wide range of health staff.