Artificial Sweeteners' effect on the Gut Microbiome and their potential to influence Athletic performance

  1. Artifical Sweeteners (Overview)
  1. The Gut Microbiome and its potential impact on Athletic Performance
  1. Artifical Sweeteners direct or indirect influence on Athletic Performance

2.The Gut Microbiome

  1. Artifical Sweeteners' potential to alter the gut microbiome

1.1 History of Artificial Sweeteners

Sugar substitutes not metabolized by the body and often many times sweeter than sugar.

1.2 Common Sweeteners used today

Aspartame, Acesulfame potassium, Monk fruit extract, Neotame, Saccharin, Stevia, Sucralose and Advantame (8 approved by FDA)

2.1 Structure and function of the microbiome

200 prevalent types of of bacteria, fungi, virus,es and archaea that inhabit the human gastrointestinal tract

These diverse populations of bacteria bring about beneficial effects via fermentation of dietary fiber to procue short chain fatty acids and provide unique metabolic functions that are cruical in maintaining heatlh

2.2 Disease states associated with an altered microbiome

Been implicated in a host of chronic diseases, including IBD, Type 2 diabetes, and cardiovascular disease

Introduced in late 1800s, became popular as a dietary aid in the 1950s claims that it caused bladder cancer in rats not reproducible in humans

Link between obesity, BMI and dysbiosis

Low bacterial richness individuals have greater adiposity, insulin resistance, and higher levels of inflammation

Protection of disease, regulation of metabolism, production of neurotransmitters, and the interaction with the enteric and central nervous system via the gut-brain axis

3.1 Associations between sweeteners and altered metabolic function due to microbiome disruption

Studies show that compositional and functional changes in the microbiome following a high intake of NAS include metabolic dysfunction and glucose intolerance (mice and humans)

Chronic consumption of sucralose is in young healthy non insulin resistant males with normal BMI can induce insulin resistance

3.2 Potential mechanisms of action that lead to diseased states

Sweeteners can act on the T1R4 taste receptors of enteroendocrine cells and stimulate secretion of gut hormones implicated in the up regulation of SGLT1

NOVEL FIGURE T1R4 receptors

Studies show sucroalose stimulation of sweet taste recepotros in GLUtag cells lead to glucagon like Peptide 1 and gastric inhibitory polypeptide

4.1 Athlete associated gut Microbiota profiles

Elite athletes (rugby players) have more diverse microbiota than sedentary individuals of the same BMI, as well as enhanced metabolic pathways (increased amino acid and carbohydrate metabolism) and microbial produced short-chain fatty acids associated with performance

Relative abundance of bacteria differs between types of sports (strength vs endurance) possible association with diet

4.2 Bacteria associated with improved performance

A. muciniphilia, a mucin degrading bacterium associated with positive metabolic function may be more present in athletes than non-athletes. It can contgrol mucus reduction in mice and reduce gut permeability

Veinolla atypica is enriched in the gut microbiome of marathon runners, associated with increased endurance, reduced pro inflammatory cytokines, and increased conversion of lactate to acetate

Athletes have been noted to have lower levels of circulating LPS compared to sedentary controls, possibly due to reduced intestinal permeabiltiy

M. Smithii is more prelavent in endurance cyclists, associated with increased fermentation efficiency of the gut. Increased fermentation of SCFA could be absorbed by hosts to enchance recovery and performance

4.3 Probiotics and prebiotics' effect on microbiome-associated health outcomes

Probiotic interventions with Lactobacilli have been shown to reduce the risk and severity of respiratory and gastrointestinal symptoms in male elite distance runners, as well improving run time to fatigue

Four week supplementation protocol with Lactobacilli and Bifidobacterium reduces severity and incidcence of GIT symptoms during training and in marathon racing

5.1 How Glucose intolerance, insulin resistance and metabolic dysfunction (as shown to be consequence of dysbiosis) could negatively influence athletic performance

5.2 How artificial sweeteners could indirectly
induce Gastrointestinal distress during training and racing by inducing gut dysbiosis and increasing permeability