The sweet truth about sugar alternatives might be bitter! Recent research reveals a shocking fact: sorbitol, a sugar alcohol commonly used as a sweetener, may not be as harmless as we once believed. But here's the twist: it's not just about sorbitol.
A study published in Science Signaling by Gary Patti and his team at Washington University in St. Louis has uncovered a connection between sorbitol and liver disease. They found that sorbitol, which is just one step away from becoming fructose, can have similar harmful effects on the liver as fructose itself. This is particularly concerning given that fructose is known to contribute to steatotic liver disease, affecting a significant portion of adults worldwide.
The research delved into the metabolism of sorbitol, which is naturally produced in the gut from glucose after eating. Interestingly, the enzyme responsible for sorbitol production has a low affinity for glucose, requiring high glucose levels to kick into action. This is why sorbitol production has been linked to diabetes, where blood glucose levels can spike. However, the study found that even in healthy individuals, glucose levels in the gut can rise high enough after meals to trigger sorbitol production.
The presence of specific bacteria in the gut plays a crucial role. Sorbitol-degrading Aeromonas bacterial strains can convert sorbitol into harmless byproducts. But without these bacteria, sorbitol remains undegraded and is passed on to the liver, where it's converted into a fructose derivative. This is a potential concern for people with diabetes or metabolic disorders who rely on 'sugar-free' products containing alternative sweeteners.
The issue arises when sorbitol levels exceed the gut bacteria's capacity to clear it. This can happen when there's excessive glucose consumption, leading to high levels of glucose-derived sorbitol, or when dietary sorbitol intake is too high. And here's the catch: even if someone has the right bacteria, high levels of glucose and sorbitol consumption may overwhelm these helpful microbes.
The challenge of avoiding sugar and alternative sweeteners is further complicated by their widespread use in various foods. Patti's own experience with his favorite protein bar, which contained sorbitol, highlights this dilemma. The team's future research aims to uncover the exact mechanisms by which bacteria clear sorbitol, as the current assumption that sugar alcohols are harmlessly expelled may not be entirely accurate.
The study concludes that the quest for sugar alternatives may not be as straightforward as we'd like. With sorbitol and other sugar alcohols potentially leading to liver dysfunction, it seems there's no easy way out. And this is the part most people miss: the hidden dangers of seemingly healthy alternatives.
