Key Points
- Artificial and natural sweeteners, such as sucralose and stevia, are used as alternatives to sugar.
- Sweeteners can change healthy people’s gut microbiomes.
- This slows the processing of sugar. How the microbiome affects sugar processing is not yet known.
Research suggests that rather than being a healthy alternative to sugar and aiding in controlling blood sugar, sugar substitutes could be doing surprising damage.
In an experiment, after two weeks of eating sugar substitutes, healthy adults had less control over their blood sugar levels.
Published in Cell, the study also found these substances changed gut health – the gut microbiome was found to have started functioning like that of a person with diabetes.
“We were able to show why sweeteners disrupt the gut microbiome and consequently affect human metabolic health,” Johns Hopkins microbiome researcher said.
Sucralose, a sweetener, triggered the biggest microbiome change in study participants.
According to ABC News, consuming sugar substitutes, especially artificial sweeteners, has been linked to conditions such as type 2 diabetes. However, that’s not enough to say sweeteners cause the condition. It could be that people with diabetes simply choose to consume more sugar substitutes.
In 2020-21, almost a quarter of Australian adults report sipping on diet drinks at least once a week, with 7 per cent doing so daily.
Even if you do not go out of your way to consume them, likely, you do anyway. There are a lot of stealth sweeteners in our food.
Our gut microbiome breaks down food, and it can affect our body.
Different bacteria secrete different chemicals into our blood, and these compounds can affect how our organs work.
What happens to blood glucose after I eat?
- When you eat digestible carbohydrates such as starches, your digestive system breaks them down into glucose, a type of sugar your body’s cells use as energy.
- That glucose enters your blood, raising your blood sugar levels.
- Soon after, your body secretes insulin – a hormone that brings blood sugar levels down to pre-meal levels.
- If blood sugar levels remain too high for too long, they can damage the body’s nerves and organs, including the eyes, kidneys and heart.
“We don’t know why some groups of bacteria go extinct in the presence of each sweetener. Maybe the sweeteners are toxic, or maybe they affect some specific energy metabolism of the bacteria,” Dr Suez said.
Sweeteners might also change cells in the intestinal lining, which could make parts of the gut more habitable for some bacteria and change the microbiome composition.
The study participants who saw changes in their microbiome and ability to handle blood sugar started heading back to pre-sweetener levels after they finished the two weeks.
Next, Dr Suez said he would like to tease out why some people responded strongly to sweeteners while others had barely any effect.
“We might use this information to predict which microbiome will be responsive to sweeteners … and maybe develop a tool or algorithm to predict who will respond and not respond to sweeteners.”
