Eating a specific type of sweetener could raise your risk of suffering from liver disease, a study suggests.
Scientists found that sorbitol, a sugar alcohol used as a sugar substitute added to some diet sodas, sugar-free gums, low-sugar candy, ice cream and desserts, as well as some low-calorie fruit drinks, could raise the risk of fatty liver disease.
Suffered by nearly 100 million Americans, fatty liver disease is a condition in which dangerous fat builds up in the liver, triggering inflammation, scarring and even liver failure.
Researchers at Washington University in St Louis found in tests on zebrafish that sorbitol, used as a sugar substitute because it is much lower in calories, was naturally produced in the gut when glucose levels were high but was usually cleared by healthy gut bacteria.
When those bacteria were removed, which commonly occurs in humans who take certain medications, however, the sorbitol traveled to the liver, where it accelerated fat build-up. This happened because the sorbitol was converted into fructose, which was then converted into fat.
The scientists wrote in their research paper: ‘Together, these findings show that sorbitol-degrading bacteria in the gut protect against [fatty] liver disease.
‘It suggests that excessive intake of dietary sorbitol may pose a risk for the development of [fatty liver disease].’
The tests were carried out in fish and will need to be repeated in humans to confirm the results, although the researchers said it was a clear warning about the risks posed by sorbitol.
It has been widely reported that President Trump frequently enjoys a diet soda, which sometimes contains sorbitol (file photo)
Sorbitol is a sugar alcohol found naturally in fruits like apples and peaches, but is also manufactured for use as a low-calorie sweetener.
Fatty liver disease can be caused by being overweight or obese, resistance to insulin, being diabetic or having high levels of fat in the blood.
It does not always cause symptoms, and doctors say the majority of cases are undiagnosed. Some warning signs can include abdominal pain, a feeling of fullness, extreme exhaustion or weakness.
Other symptoms include nausea, loss of appetite, unexplained weight loss, yellowish skin and whites of the eyes, swelling in the abdomen, legs, feet or hands.
Without treatment, the condition can progress to scarring of the liver, which can then cause liver failure, although it can take years to reach this state.
To treat the condition, patients may be prescribed medications, told to lose weight or advised to avoid alcohol.
In severe cases, a liver transplant may be needed.
In the study, published in Science Signaling, the researchers found that sorbitol could be made in the gut naturally by an enzyme that was activated whenever glucose, sugar levels, were too high.
Normally, they said, it was neutralized by Aeromonas bacteria, which is found in Zebrafish and in humans only when it is causing an infection – it is not part of the natural human microbiome, although the researchers said other bacteria could fulfil the same role.
It was not clear how much sorbitol someone might need to consume to raise their risk of fatty liver disease, or how much sorbitol can be safely neutralized by the microbiome.
Sorbitol is a sugar alcohol used as a sugar substitute added to some diet sodas, sugar-free gums, low-sugar candy, ice cream and desserts, as well as some low-calorie fruit drinks
Dr Gary Patti, a metabolism researcher from Washington University in St Louis, who led the study, said: ‘[Sorbitol] can be produced in the body at significant levels. But, if you have the right bacteria, turns out, it doesn’t matter.
‘However, if you don’t have the right bacteria, that’s when it becomes problematic. Because in those conditions, sorbitol doesn’t get degraded and, as a result, it is passed onto the liver.’
The researchers behind this study have also previously warned that fructose has negative health effects, including turbo-charging cancer cells.
Fructose — which is also added to thousands of foods and drinks — was found to speed up the growth of certain kinds of skin, breast and cervical tumors.
Their study, published in December last year, showed this type of sugar gets converted by the liver into components that tumors need to build new cells and grow.
The more quickly a tumor grows, the more aggressive the cancer may become, able to take over a person’s body before it can fight back.
Fructose is a sugar that is extracted from sources like corn and added to processed foods, most commonly in the form of high fructose corn syrup.
Some early studies have suggested that eating more of these processed sugars might not just accelerate cancer growth, but could also be a cause of some kinds of cancer.
Added fructose is different from fruit fructose, a natural sugar found in fruits that is typically accompanied by fiber and other nutrients that slow down its absorption into the blood.
In the US, manufacturers are generally allowed to add fructose to foods without limitation, which means it’s found in high amounts in many different processed foods.
