Fiber-rich foods are important component of a healthy diet.

Are you not seeing the results you were expecting from your new and improved dietary habits? A recent study suggests that the reason may be found inside your gut.

The gut microbiome is progressively becoming of more interest to nutrition science researchers as we discover how those bacteria, archaea, viruses and eukaryotic microbes that reside in our digestive systems influence health. Gut microbiota has been connected to risk for various disease conditions, how well we age, our emotional behaviors, and there is a growing body of research regarding how it influences weight management. Healthy adults typically house over 1,000 species of bacteria in their gut, and recent research suggests that we all fall into one of three enterotypes, our genetically inherent digestive population characteristics, which do not appear to have any connection to gender, age, nationality, body mass index, or other individual characteristics. Type 1 is characterized by high levels of Bacteroides, type 2 has a higher concentration of Prevotella, and type 3 shows significant numbers of gram-positive Ruminococcus. Although there are a number of lifestyle-related factors in the composition of our digestive ecosystem (especially dietary behaviors), it is largely genetic. Recent research is finding that our enterotype may have significant health implications, specifically in how our body responds to different dietary input and what dietary behaviors may be best for us to reach our physical goals.

In effort to expand the understanding of the influence of the gut microbiome and dietary fiber content on weight management, researchers randomly assigned 62 overweight patients to two different diets for a 26-week study period. The research group was assigned to the “New Nordic Diet,” which is much like other contemporary diets in that its focus is on whole, nutrient- and fiber-dense foods, but centered around foods common in traditional Nordic cuisine. The control group was assigned a version of the modern Danish diet, which is similar to the “New Nordic Diet,” but places less emphasis on whole foods and fiber content. Both diets were similar in total caloric intake, promoting a negative energy balance. Weight, body measurements, and other common metrics of health were taken before the start and after the completion of the research period. Following the completion of the research period, participants were separated by enterotype for further evaluation. While those on the “New Nordic Diet” had better overall results, with an average weight loss of 3.5 kg, as compared to 1.7 kg for those in the control group, there were significant variations in results dependent on enterotype. For instance, those who had high levels of Prevotella in their intestine (enterotype 2) and followed the high fiber diet lost more than twice as much weight overall than those with low levels (enterotype 1) who followed the same diet. Furthermore, outside of those participants with enterotype 2, which diet was followed had no statistically measurable influence on how much weight was lost. What these finding suggest is that for those of enterotype 2, a whole food and dietary fiber-rich diet appears to be very effective in helping to manage weight. For those of other enterotypes, overall energy balance seems to be the primary factor. While recent research has provided evidence that the single best indicator of a “healthy” diet is fiber intake, how important that roughage is for weight management appears to be highly dependent on those bugs in your belly.

Although I always promote whole food, nutrient- and fiber-rich dietary choices as the best for overall health (and I am becoming a greater supporter of probiotic supplementation), in terms of weight management it certainly isn’t the entire picture. And us scientists have yet to finish piecing together that entire puzzle. While we continue to conduct large-scale population-based studies on health outcomes resulting from specific diets, with the pro-fat PURE study being the latest to add to the debate, I am becoming progressively less convinced of their relevance to you, the individual who simply wants to know what is the best for their health. There are so many moving parts in how our body processes and uses the nutrition we provide it, and the responses are very distinct. Find out what works for you. Should you run out and get your stool analyzed or ask your physician to schedule a full microbiome screening before starting your next diet? Possibly. I’ll continue researching. But until then, get in the mindset that every meal, every workout, and every night’s sleep is another opportunity to build a healthier you.

Dr. Damian Rodriguez is the health and exercise scientist for doTERRA International, LLC. He holds a doctorate in health science, a master’s degree in exercise physiology, and countless professional certifications. He has spent most of his life researching nutrition, exercise, and the lifestyle behaviors associated with optimal health. Along with his passion for health, as someone who lives with Asperger’s Syndrome, he is also involved in bringing awareness to autism spectrum disorders. There are varying opinions about many health and fitness topics. His opinions are his own and not necessarily that of doTERRA International, LLC. Consult your healthcare provider before making any changes to diet and exercise.