New research is the latest to suggest that sustained weight loss is extremely difficult for most people. The study tracked people in the general public for over a decade and found that those who were already overweight or obese tended to stay overweight or obese. People who remained obese also appeared to have a higher risk of heart problems and dying earlier than others at a lower body mass index, or BMI. The findings highlight the challenges of weight loss, which is often framed as something anyone can do with enough willpower.
The study was conducted by researchers from the University of Nottingham in the UK. They looked at anonymised medical records from over 200,000 residents over the age of 18, using a nationally representative and government-created database of people who had visited a primary care doctor (the UK, unlike the U.S., has a completely nationalized health care system). They specifically focused on people over the age of 18 who were overweight or obese but free of known heart issues and who had their BMI checked several times during the study period (1999 to 2018).
These patients were separated into four groups: People who were overweight with a BMI between 25 to 30, and those with mild, moderate, or severe obesity, or a BMI 30 and over. They were tracked for a median length of about 11 years. During that time, the researchers found that people as a whole stayed in the same weight category they were in at the start of the study. Across all groups, the average person’s BMI rose by about one.
“The majority of adults who are overweight or obese retain their degree of overweight or obesity over the long term,” the researchers wrote in their paper, published Wednesday in BMC Public Health.
Other studies from other countries have found that people tend to not lose the weight they gain as they get older. Many have also found that sustained weight loss is difficult to achieve even for people who are trying to lose weight and succeed at it for a short while, outside of interventions like bariatric surgery.
The authors say theirs is the first and largest study of its kind to look at how BMI might change over time in the general population and how these trends could affect a person’s heart health and longevity. And on that last note, the findings weren’t encouraging either. Compared to overweight people, people who were severely obese (a BMI over 40) had a roughly threefold higher risk of heart failure as well as dying earlier from cardiovascular disease or all causes in general. This was the case after accounting for other risk factors they may have had at the start of the study.
The authors do note that BMI isn’t always a great measurement of a person’s current and future health. Different populations may carry the same risk for conditions like type 2 diabetes at a lower BMI than others, for instance. And on an individual level, a person in good health with lots of body muscle can still end up categorised as being overweight or obese.
But coupled with other evidence, the authors say there’s a clear overall link between having obesity and being at higher risk for future health problems. And right now, our current approaches to helping people avoid or treat obesity simply aren’t working. “More effective policies and weight-management interventions at societal, cultural and health service levels are needed to address this increasing burden,” the study authors wrote.
Even now, TV shows like “The Biggest Loser” (resurrected last year) frame weight loss as a matter of willpower, often at the cost of the contestants’ own health. Scientists are currently researching new medical approaches to weight loss, including ongoing trials of a diabetes drug that seems to both reduce weight and improve other markers of health, like blood pressure.