Does weight loss surgery help with problem eating habits?
More Australians are turning to surgery to help treat obesity – but once their surgery is over, what impact does it have on patients' eating habits in the long term?
The complex answers to that question are being uncovered by new research from the University of Adelaide. Researchers in the University's Faculty of Health Sciences have just published the findings of a review into weight-loss surgery and changes in eating habits, and are now seeking participants for a new study.
As part of her research, PhD student Melissa Opozda conducted a review of 23 previous studies from 1990-2015. Her findings – published this week in the journal Obesity Reviews – have revealed that some types of surgery can have short to medium-term success in changing people's eating habits. The review also found many gaps in the knowledge, highlighting the need for further studies.
Currently 28% of Australians (4.9 million) are obese. Many are turning to bariatric (weight loss) surgery, which is considered to be the most effective available long-term intervention for weight and related health issues.
"Before surgery, people commonly report long-term problem eating patterns, including binge eating disorder, grazing, night eating, and emotional eating. They hope that surgery will lead not only to weight loss but also to better eating habits," Ms Opozda says.
"Despite the large number of surgical procedures being performed each year to treat obesity, there is just not enough research to date to clearly understand the effects of these surgeries on how people eat," she says.
There are three main types of bariatric surgery carried out in Australia: Roux-en-Y gastric bypass, adjustable gastric banding (also known as "lap banding") and vertical sleeve gastrectomy.
"As these surgeries involve very different changes to the body and have different weight and health outcomes, we wanted to look at the evidence on whether they might also have different effects on the problem eating behaviours that we know are common before weight-loss surgery," says one of Ms Opozda's supervisors, Professor Gary Wittert from the University of Adelaide's School of Medicine.
"The review found short and medium-term reductions in binge eating, short to medium-term reductions in emotional eating, and potential short to long-term reductions in bulimic symptoms after gastric bypass. However, there was little research on sleeve gastrectomy, and few consistent findings about gastric banding," Professor Wittert says.
Professor Anna Chur-Hansen from the School of Psychology, another of Ms Opozda's supervisors, says: "The existing research suggests that for some patients, binge eating behaviours may reoccur and even occur for the first time after both gastric bypass and gastric banding. This is a worrying finding that needs further investigation."
M. Opozda et al. Changes in problematic and disordered eating after gastric bypass, adjustable gastric banding and vertical sleeve gastrectomy: a systematic review of pre-post studies, Obesity Reviews (2016). DOI: 10.1111/obr.12425