Diet-induced extinctions in the gut microbiota compound over generations

Abstract

The gut is home to trillions of microbes that play a fundamental role in many aspects of human biology including immune function and metabolism 1,2. The reduced diversity of the Western microbiota compared to populations living traditional lifestyles presents the question of which factors have driven microbiota change during modernization. Microbiota accessible carbohydrates (MACs) found in dietary fiber, play a key role in shaping this microbial ecosystem, and are strikingly reduced in the Western diet relative to more traditional diets 3. Here we show that changes in the microbiota of mice consuming a low-MAC diet and harboring a human microbiota are largely reversible within a single generation, however over multiple generations a low-MAC diet results in a progressive loss of diversity, which is not recoverable upon the reintroduction of dietary MACs. To restore the microbiota to its original state requires the administration of missing taxa in combination with dietary MAC consumption. Our data illustrate that taxa driven to low abundance when dietary MACs are scarce are inefficiently transferred to the next generation and are at increased risk of becoming extinct within an isolated population. As more diseases are linked to the Western microbiota and the microbiota is targeted therapeutically, microbiota reprogramming may need to involve strategies that incorporate dietary MACs as well as taxa not currently present in the Western gut.

Nutrition, oxidative stress and intestinal dysbiosis: Influence of diet on gut microbiota in inflammatory bowel diseases

“…In the human gut, there are trillions of microorganisms which together are known as microbiota 3,4 . Intestinal bacteria have the highest concentration, approximately 100 trillion, with a density of 9x10 [13][14] and considerable biodiversity (approximately 1000 bacterial species).…”

Microbes, Immunity, and Behavior: Psychoneuroimmunology Meets the Microbiome

“…It has been suggested that diet may be the easiest way to alter the host microbiota and that such changes may come about rapidly (Wu et al, 2011). However, a recent study in rodents suggests this may not be as easy as it seems (Sonnenburg et al, 2016). They raised mice in a germ-free (GF) environment and then transplanted a human microbiota.…”

Impact of Dietary Fibers on Nutrient Management and Detoxification Organs: Gut, Liver, and Kidneys

“…It has been proposed that individuals with more diverse gut microbiota are more adept at responding to environmental challenges (54), such as resisting colonization of gut pathogens by competitive exclusion (i.e., commensal bacteria take over niches and/or consume substrates to inhibit the growth of pathogenic bacteria) (55). Interestingly, mice fed low-fiber diets showed decreased microbial diversity, which could be recovered after the introduction of a high-fiber diet; however, after generations of feeding a low-fiber diet, microbial diversity could not be recovered after the re-introduction of fiber (56). This finding may have implications to our current population, because DF consumption has decreased since the industrial revolution (57).…”