Writing in the International Journal of Obesity, a team of Danish researchers report the findings of a study that tested the potential for using simplified microbiome enterotypes, based on the radio of certain bacterial groups, as prognostic markers for successful body fat loss on two different diets.
Led by senior author, Professor Arne Astrup at the University of Copenhagen, the team revealed that the bacteria we all have in our gut may play a decisive role in personalised nutrition and diet programs that aim to fight obesity.
"Human intestinal bacteria have been linked to the increasing prevalence of overweight and obesity, and scientists have started to investigate whether the intestinal bacteria can play a role in the treatment of overweight. But it is only now that we have a breakthrough demonstrating that certain bacterial species play a decisive role in weight regulation and weight loss" said Astrup.
They say that a simple stool sample could reveal whether people are able to lose weight by following dietary recommendations characterised by a high content of fruit, vegetables, fibres and whole grains.
According to Astrup and colleagues, the ratio between two important groups of intestinal bacteria is decisive for whether overweight people lose weight on a diet that follows the Danish national dietary recommendations and contains a lot of fruit, vegetables, fiber and whole grains.
“A total of 62 participants with increased waist circumference were randomly assigned to receive an ad libitum New Nordic Diet (NND) high in fiber/wholegrain or an Average Danish Diet (ADD) for 26 weeks,” explained the team.
Participants were grouped into two discrete enterotypes by their relative abundance of Prevotella spp. divided by Bacteroides spp. (P/B ratio) obtained by quantitative PCR analysis.
When the subjects were divided by their level of intestinal bacteria, it was found that people with a high proportion of Prevotella bacteria in relation to Bacteroides bacteria lost 3.5 kg more in 26 weeks when they ate a diet composed by the New Nordic Diet principles compared to those consuming an Average Danish Diet.
Furthermore, subjects with a low proportion of Prevotella bacteria in relation to Bacteroides did not lose any additional weight on the New Nordic Diet.
"The study shows that only about half of the population will lose weight if they eat in accordance with the Danish national dietary recommendations and eat more fruit, vegetables, fibers and whole grains,” said study co-author Professor Mads Fiil Hjorth. “The other half of the population doesn't seem to gain any benefit in weight from this change of diet.”
The team emphasised that they have already confirmed the results in two independent studies, so they are certain that these results are credible.
They added that overall, approximately 50% of the population have a high proportion of Prevotella-bacteria in relation to Bacteroides-bacteria.
"These people should focus on other diet and physical activity recommendations until a strategy that works especially well for them is identified,” said Fiil Hjorth.
Personalised nutrition approach
According to the Danish team, the study results show that biomarkers from faecal samples – in addition to other important blood and genetic markers – should play a greater role in personalising nutritional guidance.
"This is a major step forward in personalized nutritional guidance,” said Fiil Hjorth. “Guidance based on this knowledge of intestinal bacteria will most likely be more effective than the "one size fits all" approach that often characterises dietary recommendations and dietary guidance.”
Currently, the majority of work on the composition of intestinal bacteria remains in academic institutions – however a number of start-ups and microbiome profiling companies are looking to take advantage of recent developments.
Indeed, the University of Copenhagen has licensed a company in Boston, USA, to develop and publish a concept based on this research.
Source: International Journal of Obesity
Published online ahead of print, doi: 10.1038/ijo.2017.220
“Pre-treatment microbial Prevotella-to-Bacteroides ratio, determines body fat loss success during a 6-month randomized controlled diet intervention”
Authors: M F Hjorth, et al