fatty liver disease Archives - Health Tips From The Professor

Is Sorbitol Dangerous?

July 14, 2026 by Dr. Steve Chaney

Should You Avoid Foods Containing Sorbitol?

Author: Dr. Stephen Chaney

Sorbitol is in the news. And the news doesn’t seem to be good. Social media influencers are telling you:

Sorbitol can cause gastrointestinal distress (cramping, bloating, cramping, and diarrhea).

Sorbitol can cause heart attacks and strokes.

Sorbitol can cause liver disease.

They are telling you to scan every label and avoid anything with sorbitol in it. Should you listen to them, or are they promoting food myths to get more followers and clicks?

After all, sorbitol is found in lots of healthy foods such as peaches, pears, apples, nectarines, apricots, cherries, sweet corn, white cabbage, and eggplant. Should you give up those as well?

And our body produces sorbitol from other sugars, so we always have some sorbitol circulating through our bloodstream.

In short, sorbitol is not a foreign substance. It’s not an artificial sweetener. Our body knows how to handle it safely.

But every food myth starts with a kernel of truth. So, let me discuss each of these claims and separate the kernel of truth from the myth.

Can Sorbitol Cause Gastrointestinal Distress?

This claim is true, but:

It is true for every sugar alcohol.
It is a matter of dose.
It is also true for the sugar alcohols found in healthy foods.

Let’s examine those last two points in more detail.

For most people, the small amount of sugar alcohols found in the foods they eat cause no problem. It’s only when they consume large amounts that they experience gastrointestinal distress. [Note: I said most people. If you have Irritable Bowel Syndrome (IBS) or Small Intestinal Bacterial Overgrowth (SIBO), you may be sensitive to even small amounts of sugar alcohols – and many other things.]

And the gastrointestinal effects of large amounts of sugar alcohols are not limited to processed foods. They can also be associated with consumption of healthy foods. Let me share my personal experiences, and you can see if you have had similar experiences.

Years ago, I had a strawberry patch and several fig bushes. At the height of their seasons, it was tempting to eat lots of strawberries and lots of figs. After all, why let those delicious fruits go to waste?

I quickly discovered that 8-10 strawberries on my breakfast cereal was a treat, but 30 strawberries at a sitting was a BIG problem. Similarly, 2-3 figs for dessert were the perfect ending to a meal, but 10 figs at a time was a BIG problem.

The take-home lesson was clear. Small amounts of sorbitol and other sugar alcohols in healthy foods and supplements are no problem. Our body knows how to handle them. But large amounts of sorbitol and other sugar alcohols can cause gastrointestinal distress. And it doesn’t matter if those large amounts come from healthy foods or unhealthy processed foods.

Can Sorbitol Cause Heart Attacks And Strokes?

Human heart attack time bomb as a symbol of urgent health problems due to poor cholesterol levels and bad diet eating fatty greasy junk food.

This claim is mostly false. In the first place, the study on which this claim is based was done with erythritol, not sorbitol. More importantly, the study was deeply flawed.

I have described the flaws in a recent issue of “Health Tips From the Professor”.

In addition to its many flaws the study only found an association between erythritol and heart disease at very high intakes of erythritol. Specifically:

There was no association between erythritol and heart disease at low to moderate intakes of erythritol. As with sorbitol, erythritol is found in many healthy foods and our bodies know how to handle the amount of erythritol found in healthy foods and supplements.

The association between erythritol and heart disease was only seen at intakes of 30 grams/day or above. The only way you could get that much erythritol daily would be to consume a diet with lots of erythritol-sweetened highly processed foods. And we already know a diet of highly processed foods is associated with an increased risk of heart attack and stroke.

After reviewing the study and analyzing its flaws, I concluded,” Clearly, it doesn’t matter what sweetener we are talking about. Large intake of any natural sweetener in the context of a diet rich in highly processed foods appears to have an adverse effect on our health. And we don’t know whether these adverse health effects are caused by the sweetener or some other components of the highly processed foods.

If you want to improve your health, the best solution is to decrease your intake of highly processed foods. That will automatically reduce your intake of sweeteners and other unhealthy components of highly processed foods and increase your intake of healthy components from the whole foods you will be eating instead”

Many other experts have come to a similar conclusion after reviewing that study.

However, that hasn’t kept social media influencers from warning you to read labels and avoid everything with sorbitol in it because it increases your risk of heart attack and stroke. And, unfortunately, some respectable web sites have repeated that claim without examining the study behind the claim.

Can Sorbitol Increase The Risk Of Liver Disease?

This claim is also mostly false. The study behind this claim was done in zebrafish, not humans. And the zebrafish were put on antibiotics that wiped out their intestinal bacteria. Under these conditions, when the zebrafish were fed glucose, they developed fatty liver disease.

I realize that description of the experimental protocol has probably left you confused. So, let me walk you through the metabolic rationale for the study.

In zebrafish, like in humans, a small amount of dietary glucose is converted to sorbitol by intestinal mucosal cells.

In zebrafish and humans, the small amount of sorbitol produced in the intestine is degraded by intestinal bacteria. No harm, no foul.

However, when the intestinal bacteria are wiped out, sorbitol accumulates and is absorbed into the bloodstream. Simply put, this was way to create very high blood levels of sorbitol in zebrafish.

Zebrafish and humans are both able to metabolize small amounts of sorbitol. But when the blood levels of sorbitol are high enough, the normal metabolic pathways are overwhelmed.

Under these conditions, sorbitol goes to the liver where it is converted to fructose.

Previous studies have shown that excess fructose in the liver can cause fatty liver disease.

The authors of this study concluded, “These results indicate that sorbitol is derived from glucose in the zebrafish intestine, implicate gut microbiota [gut bacteria] in protecting against sorbitol-induced steatosis [abnormal accumulation of fat], and suggest that dietary sorbitol, which is used as a sugar substitute, may increase the risk of developing steatotic liver disease [fatty liver disease].”

This is the message you have probably seen from social media influencers and some websites. Of course, they consider “fatty liver disease” to be too complicated, so their warnings are usually that sorbitol can cause liver disease or liver “danger”.

It sounds scary, but this claim ignores the flaws in this study. In the first place, the study was conducted with zebrafish with no intestinal bacteria. We don’t know whether this is true for humans under normal conditions. And if it is true, it required high blood levels of sorbitol which can only be attained in humans by eating lots of highly processed sorbitol-sweetened foods.

And to put this in proper perspective we also need to investigate the link between fructose and fatty liver disease, as I have done in previous issues of “Health Tips From the Professor”.

Fructose or “fruit sugar” is, as the name suggests, found in almost all fruits.

Fructose in fruits is present in small amounts and is encased with fiber, so it is absorbed slowly.

Our bodies are designed to handle the fructose found in fruits. It is slowly converted to glucose, avoiding the blood sugar spikes associated with sucrose (table sugar) and glucose consumption.

Fructose in highly processed foods is present in much larger amounts with no fiber to slow its absorption into the bloodstream.

Under these conditions, our normal metabolic pathways for dealing with dietary fructose are overwhelmed. Fructose accumulates in the liver, where it is converted to fat.

If we consume highly processed fructose-containing foods long enough, we develop fatty liver disease.

Is this starting to sound familiar? In short, fructose, erythritol, sorbitol, and other sugar alcohols are not a problem in the small doses found in supplements and healthy foods. They only become a problem when we consume lots of processed foods that use them as sweeteners.

Is Sorbitol Dangerous?

The short answer is, “No”. You can ignore the dire warnings about the dangers of sorbitol. They are food myths! You don’t need to become a label reader and avoid every supplement and food with sorbitol on the label.

Here is the truth about sorbitol:

#1: It can cause gastrointestinal distress (cramping, bloating, cramping, and diarrhea) if you eat too much sorbitol-containing foods at one time. Other studies suggest that this occurs for most people at doses of 10-15 grams of sorbitol. This can occur with excess consumption of both healthy foods and processed foods that are high in sorbitol.

And most of us figure out pretty quickly which foods are a problem for us. That doesn’t require label reading. It just requires paying attention to our symptoms.

#2: The claims about increased risk of heart disease and liver disease are mostly false.

The claim that sorbitol increases the risk of heart disease was based on a study with erythritol, not sorbitol, and the study was highly flawed.

The claim that sorbitol increases the risk of liver disease was done with zebrafish, not humans.

If those studies tell us anything, it is that health issues associated with sorbitol consumption only occur at high doses which can only be achieved by eating lots of sorbitol-sweetened highly processed foods.

There is no evidence of health issues associated with the small amounts of sorbitol found in some supplements and healthy foods. Our bodies are designed to handle small amounts of sorbitol because they occur naturally in a healthy diet containing fruits and vegetables.

I suppose you could read the labels of processed foods and avoid the ones containing sorbitol. However, there are lots of health concerns with highly processed foods. Sorbitol is the least of the concerns.

A better choice would be to avoid highly processed foods. You don’t need to read their labels to know they are bad for you.

The Bottom Line

We are constantly bombarded with new food ingredients we need to avoid. Social media influencers are telling us to scan food and supplement labels, so we know which ones we shouldn’t eat.

The latest warnings are about sorbitol, a sugar alcohol that occurs naturally in healthy foods and is also added to processed foods. We are being told that:

Sorbitol can cause gastrointestinal distress (cramping, bloating, cramping, and diarrhea).

Sorbitol can cause heart attacks and strokes.

Sorbitol can cause liver disease.

are telling you to scan every label and avoid anything with sorbitol in it. Should you listen to them, or are they promoting food myths to get more followers and clicks?

Here is the truth about sorbitol:

The claim that high levels of sorbitol can cause gastrointestinal distress are mostly true, but they are equally true for healthy foods and processed foods that are high in sorbitol.

And most of us figure out pretty quickly which foods are a problem for us. That doesn’t require label reading. It just requires paying attention to our symptoms.

The claims that sorbitol increases our risk heart and liver disease are mostly false. They are based on flawed studies that were not done with sorbitol in humans.

- If those studies tell us anything, it is that health issues associated with sorbitol consumption only occur at high doses which can only be achieved by eating lots of sorbitol-sweetened highly processed foods.

- There is no evidence of health issues associated with the small amounts of sorbitol found in some supplements and healthy foods. Our bodies are designed to handle small amounts of sorbitol because they occur naturally in a healthy diet containing fruits and vegetables.

A better choice would be to avoid highly processed foods. You don’t need to read their labels to know they are bad for you.

For more details, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

___________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

______________________________________________________________________

About The Author

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years. Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”. Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry textbooks for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 53 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

Is It The Sugar Or Is It The Food?

July 26, 2022 by Dr. Steve Chaney

Is Fructose Bad For You?

Author: Dr. Stephen Chaney

I don’t usually report on studies done in mice, but this study sheds light on a particularly puzzling question: Why is fructose bad for us?

The studies are clear-cut. High fructose consumption is associated with inflammation, obesity, non-alcoholic liver disease, insulin resistance, type 2 diabetes, kidney disease, increased LDL cholesterol and triglycerides, and heart disease. Based on these associations, fructose appears to be deadly. Why would anyone want to consume it?

Yet fructose is found in virtually every fruit. In fact, fructose, also known as fruit sugar, was first isolated from fruits. Hence the name fructose. Humans have been eating fruits safely for thousands of years. Fruits are very good for us. That raises the question: “If fruits are good for us, how can fructose be bad for us?”.

An important clue can be found by looking at what the food industry has done to the American diet. Because fructose imparts a pleasurable, sweet taste to foods the food industry keeps adding it to more and more foods. As a result, dietary intake of fructose has increased 100-fold over the past two centuries. It has reached the point where fructose now accounts for almost 10% of the caloric intake in the United States.

Is It The Sugar, Or Is It The Food?

Let me expand the discussion by using a couple of graphics I developed for my book, “Slaying The Food Myths”

There Are No Sugar Villains. There Are No Sugar Heroes:

Virtually all sweeteners are primarily a mixture of fructose and glucose. The graphic on the left compares high fructose corn syrup (the current villain) with other “natural” sweeteners used in foods (our current heroes). High fructose corn syrup ranges from about 40% fructose to 55% fructose. The exact percentage depends on what kind of food product is being made with it.

Honey and coconut sugar are about 45% fructose. Sucrose and grape juice concentrate are around 50% fructose. Apple juice concentrate is around 60% fructose, and agave sugar comes in at a whopping 80% fructose.

In other words, if fructose is the culprit that everyone makes it out to be, “healthy” sugars are no better than high fructose corn syrup. Simply substituting a “healthy” sugar for high fructose corn syrup is unlikely to provide any meaningful benefit.

Is It The Sugar, Or Is The Food?

This graphic shows us what a nutrition label would look like on a medium apple. I am sure that label is a wake-up call for many of you. The amount of sugar and the percentage of fructose and glucose are about the same as in an 8-ounce soda sweetened with high fructose corn syrup. The same is true for virtually every other fruit you can think of.

Now let me share one more thing you won’t hear from what I refer to as “Dr. Strangelove’s Health Blog” (You probably know the ones I am referring to). Virtually all the studies showing the bad effects of fructose consumption have been done with sodas and sugary junk foods. They haven’t been done with apples.

In fact, virtually every study looking at fruit and vegetable consumption has shown they are incredibly good for us. They lower inflammation and reduce the risk of obesity, diabetes, heart disease, and cancer. And the more the better. One study found that the health benefits of fruit and vegetable consumption topped out at around 10 servings a day.

With this background, you should now fully understand why the question “If fruits are good for us, how can fructose be bad for us?” is so perplexing.

My simplistic explanation has always been that whole foods like fruits have fiber, which slows the absorption of fructose from the intestine. Our bodies were designed to handle fructose in a safe manner when it enters the bloodstream slowly. It is taken up by the liver, converted to glucose, and then slowly metered back into the bloodstream. This provides our brain and other tissues with the glucose they need for energy without blood sugar spikes. This is how fructose is supposed to be metabolized by our bodies.

Sodas and junk foods, on the other hand, have little to slow the absorption of fructose. When lots of fructose enters the bloodstream rapidly, our “safe” metabolic pathways for handling it are overwhelmed, and it is forced into the pathways that are harmful. For example, the “excess” fructose is converted to fat by the liver, which causes inflammation, obesity, fatty liver disease, and triglyceride production.

This is, of course, simply my hypothesis for explaining the different effect of fructose in fruits and sodas. It is based on sound metabolic principles, but it is far from proven. That is why I found a recent study (C. Jang et al, Cell Metabolism, 27: 351-361, 2018) so interesting. It provides a metabolic rationale for my hypothesis.

How Was The Study Done?

Mice were fed a 1:1 mixture of fructose and glucose at doses that approximated the ranges of typical human fructose consumption. The fructose was isotopically labeled so that fructose and its metabolites could be identified by LC-MS (liquid chromatography – mass spectrometry). After feeding the mice the labeled fructose, the investigator measured the amount of fructose and its metabolites in various organs and in the portal vein, which transports sugars from the intestine to the liver for additional metabolism before they enter the bloodstream.

Is Fructose Bad For You?

The first surprise was that most of the fructose was metabolized by the intestinal mucosal cells that line the small intestine rather than the liver. Previous reports had assumed that fructose was primarily metabolized by the liver because that was where most of the bad effects of fructose metabolism had been observed.

These investigators observed that fructose was primarily converted to glucose and small molecular weight metabolites by the intestinal mucosal cells before being released into the portal vein, where they were transported to the liver. However, there was a strong dose response effect.

At low fructose doses, 90% of fructose was metabolized by intestinal mucosal cells before being released to the liver.

At high fructose doses, only 70% of fructose was metabolized by intestinal mucosal cells.

That means at high fructose doses the amount of fructose reaching the liver unchanged increases from 10% to 30%. That is a 3-fold increase!

The authors concluded:

“Based on these findings, we propose that the small intestine shields the liver from fructose and that excessive doses of fructose overwhelm the small intestine, spilling over to the liver where they cause toxicity.”

“A key difference between the health effects of fiber-rich fruits (and perhaps even fiber-rich prepared foods) and juices/sodas is their rate of intestinal fructose release.”

“It is likely that the appearance rate of free fructose in the small intestine plays a critical role in dictating its metabolic fate. Like the lower doses in our experiments, a slower rate of fructose appearance will result in more complete intestinal clearance, whereas higher doses and faster rates result in fructose overflow to the liver.”

This study needs to be confirmed, and the mechanism may be entirely different in humans. However, whether mechanism is the same in mice and humans is immaterial. We already know that fructose in sodas and junk foods exerts a very different effect on our health than fructose in fruits and other fiber-containing foods.

Despite what Dr. Strangelove tells you, fructose is not bad for you. It isn’t the problem. It is sodas and junk foods containing high-fructose corn syrup that are the problem. And substituting other sugars for high-fructose corn syrup doesn’t make them any better. As I showed you above, the so called “healthy” sugars are chemically and biologically indistinguishable from high-fructose corn syrup.

The Bottom Line

Previous studies have clearly shown that fructose in sodas and junk foods is bad for us, while fructose in fruits is good for us. A recent study in mice provides a metabolic explanation for this difference. The study found:

At low fructose doses, 90% of fructose was metabolized by intestinal mucosal cells before being released to the liver.

At high fructose doses, only 70% of fructose was metabolized by intestinal mucosal cells.

That means at high fructose doses the amount of fructose reaching the liver unchanged increases from 10% to 30%. That is a 3-fold increase!

The authors concluded:

“Based on these findings, we propose that the small intestine shields the liver from fructose and that excessive doses of fructose overwhelm the small intestine, spilling over to the liver where they cause toxicity.”

“A key difference between the health effects of fiber-rich fruits (and perhaps even fiber-rich prepared foods) and juices/sodas is their rate of intestinal fructose release.”

“It is likely that the appearance rate of free fructose in the small intestine plays a critical role in dictating its metabolic fate. Like the lower doses in our experiments, a slower rate of fructose appearance will result in more complete intestinal clearance, whereas higher doses and faster rates result in fructose overflow to the liver.”

For more details, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.