Researchers have identified the potential for lifestyle changes to prevent and treat obesity without skill.
Weight loss surgery can reduce bile acid levels associated with a higher appetite, as can taking fiber supplements but to a lesser extent.
The study suggests that if this effect can be moderated through lifestyle changes, there may be a potential for treating and preventing obesity, a risk that can be eliminated by hand.
Research by King’s College London, the University of Nottingham and the Amsterdam University Medical Center highlights the molecular basis of the benefits of weight surgery (including bariatric surgery) on appetite and metabolism.
Bariatric surgery can be used for the treatment of very obese people.
There are also several types of reducing the size of the stomach, or cutting off the top of the stomach to the intestines.
Surgery is an invasive procedure, but it can lead to significant improvements in weight loss, metabolic health and a reduction in appetite, but the reasons are unknown.
Article lead author Dr Cristina Menni, King’s College London, said: “The results of the study have important implications for the development of targeted interventions for metabolic disorders that focus on the gut microbiome.
“By better understanding the complex interaction between genetics, the gut microbiome, and diet in regulating bile acid levels and their impact on appetite and metabolic health, we may be able to develop new strategies to prevent and treat obesity and metabolic syndrome.”
Bile acids – acids mainly made in the fluid (bile) and released by the liver and stored in the gallbladder – are a marker of poor heart and metabolic health and can affect liver function and inflammation.
Researchers in Amsterdam who had undergone bariatric surgery and measured the level of bile acids before surgery and a year after.
They also studied bile acids from two large population studies: TwinsUK, run by King’s College London; and Predict, run by King’s and personalized nutrition company, Zoe.
According to the findings, levels of a specific bile acid called isoursodeoxycholate (isoUDCA), which is associated with higher appetite and worse metabolism, fell after bariatric surgery and after fiber supplements were taken.
However, acid levels did not decrease after consuming omega-3 supplements.
Scientists say that understanding these mechanisms could enable the development of new interventions that mimic the effects of bariatric surgery without making patients suffer through an invasive procedure.
Bariatric surgery is also only suitable for those who are severely obese, and understanding whether isoUDCA can be changed through lifestyle interventions could lead to targeted obesity treatments.
Research also suggests that gut bacteria are key to determining the outcome of bariatric surgery and sheds light on the ways in which gut microbes modify a person’s metabolism.
Lead article author Professor Ana Valdes, University of Nottingham, said: “What our study shows is that a specific microbial metabolite is involved in some of these benefits and, albeit modestly, dietary fiber mimics some of these effects.
“This design could help supplement purity studies to increase satiety and enhance liver parameters.”
Co-producer Professor Tim Spector, professor of genetic epidemiology at King’s College London and co-founder of Zoe, said: “This study highlights the key role that fiber plays in the regulation and metabolism of appetite, tied to specific gut microbes.
“The introduction of gut microbiome testing (used by Zoe) uncovers personal insights that can support metabolic health.
“The gut microbiome and its chemical products such as these bile acids hold tremendous promise for reducing obesity without the need for invasive surgery.”
The findings were published in the journal Medical Reports.