Getting straight to the topic - we're talking alternative sweeteners to sugar. Sugar alcohols like Sorbitol, Erythritol, Xylitol, Maltitol, plus the well known artificial sweeteners like Sucralose, Aspartame, Saccharin and Acesulfame K are all being used to increase the sweetness of processed foods.
It's not surprising that athletes are asking questions about these sweeteners. I guess if these additives were a small niche you'd be less worried about them, but in a 2019(1) paper, sugar alcohols were reported as being destined to grow from USD$3.6B in 2019, to 6.7B by 2027. Not trivial! With various studies (see below) looking at there interactions with the gut and liver-disease, the scientific community is actively studying these food additives, and the potential long term health effects. F or athletes - should they be worried about these additives in training-racing fuels?
Sugar Alcohols - What are they, and So What?
These food additives can be derived from sugar, either naturally, or (more typical) produced through industrial manufacturing. Its commonly assumed that sugar alcohols have no calories – which is not entirely correct.
Once consumed, sugar alcohols pass into the gut where they are only partially absorbed, which is where much of their well known acute symptoms come from – bloating, gas and diarrhea (laxative effect). You can find them commonly in foods like, chewing gum, sugar-free candies, cookies, soda/soft-drinks, and in leading sports-energy bars, gels and drinks. It’s no surprise when you look at the fructose and/or sugar alcohol mixes in so many energy drinks and bars, that the #1 reason for DNFs in endurance sports is still gut/GI distress – see our paper here on that.
Beyond the acute Gut/GI Issues - Bigger Concerns?
In light of the growing use of artificial sweeteners and sugar alcohols, researchers are increasingly interested in their effects on long term health. Headline marketing would position them all as health positive, namely for oral health, and metabolic disorders (diabetes, metabolic syndrome etc.) in seeking to address the over consumption of sugar and carbohydrates.
Artificial sweeteners are reported in meta-studies (2) for their association with glucose intolerance (3), decreased insulin sensitivity (4) and obesity states (5). From a causal effect, researchers are consistent in highlighting these sweeteners having a measured change in the gut microbiome, in some cases positive, but in many cases negative.
How to Spot Them - In your fuels and foods.
Here's the common sugar alcohols to look out for - Sorbitol, Mannitol, Maltitol, Hydrogenated starch hydrolysates (mix of sugar alcohols), Erythritol, Xylitol, Isomalt, Lactitol. Hope you’ve spotted the trend here, any ingredients ending in ‘...tol’. In addition to these, you then have the artificial sweeteners like sucralose, aspartame, saccharin and Acesulfame K.
Implications for the Endurance Athlete
Optimizing fuel absorption, and mitigating gut-distress during high-intensity endurance racing is key to improving performance outcomes. If you want to know more about the physiology of gut, hydration-fuel optimization during endurance racing - check out this article.
Any fuels containing sugar alcohols and/or artificial sweeteners should be considered for switching to a fuel that uses alternatives like Monk Fruit, and stevia. From a complex carbohydrate perspective, SFuels advocates using a low osmolality, high molecular weight form like a highly branched cyclic dextrin that helps to further mitigate gut disturbance, by accelerating the transit of the fuel though the stomach (vs. glucose, fructose mixes).
At SFuels, we have chosen to avoid all forms of artificial sweeteners and sugar alcohols across all our products (checkout Race+) we develop for endurance athletes. We add Glutamine, and use highly branched cyclic dextrin to optimize 'fuel-to-muscle' acceleration, while mitigating gut/GI distress.
Trust this helps you make the best decisions for your training, your race day and the longevity of your endurance sport lifestyle.
- Fortune Business Insights, Sugar Alcohols Market Size, 2020-2027. 2019
- Sugar and artificially sweetened beverages linked to obesity: a systematic review and meta-analysis. D Ruanpeng, C Thongprayoon, W Cheungpasitporn, T Harindhanavudhi. QJM. 2017 Aug.
- Artificial sweeteners induce glucose intolerance by altering the gut microbiota. Suez et al. Nature. 2014 Oct.
- Sucralose decreases insulin sensitivity in healthy subjects: a randomized controlled trial. Alonso Romo-Romo et al. Am J Clin Nutr. 2018 Sep.
- The artificial sweetener acesulfame potassium affects the gut microbiome and body weight gain in CD-1 mice. Xiaoming Bian et al. PLoS One
. 2017 Jun.