Hungry Bacteria: Revolutionizing our Understanding of Metabolism and Diet - July 2023

Hungry Bacteria: Revolutionizing our Understanding of Metabolism and Diet - July 2023

Written By Andrea McBeth 

A traditional paradigm in nutrition has been the concept of "calories in, calories out," a straightforward model suggesting that the calories we consume are converted into energy by our cells. However, recent studies are challenging this linear view of nutrition and metabolism. These studies indicate that our gut microbiome, the unique collection of bacteria within our bodies, plays a crucial role in energy extraction and influences our response to foods. Consequently, this may lead to a paradigm shift, redefining how we perceive food, diet, and health.

An intriguing study, published in Nature recently, has suggested that the bacteria in our gut might be helping themselves to a significant portion of our daily caloric intake. The research has shown that certain types of gut bacteria can "steal" up to 100 calories a day from our diet. This figure is not an insignificant difference, especially for those who are dieting or trying to maintain a healthy weight. It underlines the importance of our microbiome's health and its impact on our metabolism. 

Further complicating the picture, a separate clinical study supporting broad work done by Eran Segal’s lab at the Weizmann Institute reveals that a personalized diet, guided by AI, showed greater success in improving glycemic control in prediabetic adults compared to the traditional Mediterranean diet. This research challenges the conventional wisdom that the glycemic index of foods is a fixed property. Instead, it presents the idea that our blood sugar response is highly individual and tied to our unique microbiome.

Even more intriguing, in another research article from Tily et. al,, advanced metatranscriptomic technology was employed to investigate the gut microbiome's activity and its correlation with the postprandial glycemic response (PPGR) among adults. The study found a strong link between the activity of certain microbial genes and individual blood glucose responses to meals. Not only does this study corroborate the notion that our microbiome influences our glycemic response, but it also introduces a new layer of complexity by demonstrating that it's not merely the presence of certain bacteria that matters. Instead, what those bacteria are doing—what genes they're expressing—that plays a crucial role.

In essence, these studies collectively prompt us to think about our microbiome as an intricate participant in our metabolism, challenging the "calories in, calories out" model. It invites us to consider the possibility that the types of foods we eat could be shaping our microbiome and, in turn, determining how many calories we extract from our diet and how our blood sugar does or does not spike after a meal. Moreover, it paints a picture of an intricate, dynamic system where the metabolic outcomes are determined by a multitude of factors, including the individual's unique microbiome activity and the food's macronutrient content.

This evolution in understanding poses a profound impact on how we approach diet and weight management strategies. The key takeaway is that the microbiome is not just a passive resident of our gut but an active participant in our metabolism, behaving almost as an endocrine organ. Rather than focusing solely on calorie counting or strict macronutrient proportions, it may be beneficial to consider our unique microbiome health and its needs. By doing so, we might not only improve our metabolism but also our overall health, sparking a new era of personalized nutrition and health care. 

As we continue to unravel the complexities of the microbiome, we may soon look at a plate of food not just in terms of calories or carbohydrates but as a tool to shape our microbiome and, by extension, our health.


References:

Corbin, K. D., Carnero, E. A., Dirks, B., Igudesman, D., Yi, F., Marcus, A., Davis, T. L., Pratley, R. E., Rittmann, B. E., Krajmalnik-Brown, R., & Smith, S. R. (2023). Host-diet-gut microbiome interactions influence human energy balance: a randomized clinical trial. Nature Communications, 14(1), 3161.

Ben-Yacov, O., Godneva, A., Rein, M., Shilo, S., Kolobkov, D., Koren, N., Cohen Dolev, N., Travinsky Shmul, T., Wolf, B. C., Kosower, N., Sagiv, K., Lotan-Pompan, M., Zmora, N., Weinberger, A., Elinav, E., & Segal, E. (2021). Personalized Postprandial Glucose Response-Targeting Diet Versus Mediterranean Diet for Glycemic Control in Prediabetes. Diabetes Care, 44(9), 1980–1991.

Tily, H., Patridge, E., Cai, Y., Gopu, V., Gline, S., Genkin, M., Lindau, H., Sjue, A., Slavov, I., Perlina, A., Klitgord, N., Messier, H., Vuyisich, M., & Banavar, G. (2022). Gut Microbiome Activity Contributes to Prediction of Individual Variation in Glycemic Response in Adults. Diabetes Therapy: Research, Treatment and Education of Diabetes and Related Disorders, 13(1), 89–111.


Summary Bullets:

  1. Our gut microbiome, the unique collection of bacteria within our bodies, is not just a passive resident but an active participant in our metabolism and plays a crucial role in our response to food.
  1. The "calories in, calories out" model may not be as straightforward as we once thought. Instead, the types of foods we eat could be shaping our microbiome, determining how many calories we extract from our diet. 
  1. A personalized diet, guided by machine learning algorithms that consider both clinical and microbiome features, has shown greater success in improving glycemic control in prediabetic adults than the traditional Mediterranean diet.
  1. Advanced research has demonstrated a strong link between the activity of certain microbial genes in our gut and individual blood glucose responses to meals, adding another layer of complexity to the role of the microbiome.
  1. The evolving understanding of the microbiome's role in our metabolism may lead to a new era of personalized nutrition and healthcare, considering our unique microbiome health and its needs rather than focusing solely on calorie counting or strict macronutrient proportions.