Polyols are popular as a sugar replacement. However, some people worry that replacing sugar with sweeteners like polyols may negatively affect digestive health, metabolism and weight management. Is this true? Keep reading to find out what polyols are and how they can affect your health.
What are Polyols?
Polyols are also called sugar alcohols or bulk sweeteners. They are a type of carbohydrate found naturally in certain fruits and vegetables. They can also be manufactured to be used as food additives. Polyols contain fewer calories than ordinary table sugar (0-3 calories per gram vs. 3.75-4 calories per·gram). Some types taste as sweet as table sugar, while others have half its sweetness (1). The latter type are often added to food products to both add bulk and sweetness. They can also be mixed with artificial sweeteners like aspartame and sucralose. Polyols are a FODMAP food, and are slowly absorbed and quickly fermented in the gut. This means they can cause bloating, stomach pain and diarrhea, especially for those who have irritable bowel syndrome (IBS) (2).
Common Polyols Found in Food
Summary: Polyols are a type of carbohydrate that occur naturally in some fruits and vegetables, or are man-made to be used as sweet food additives. They are also a FODMAP food, so can irritate the gut.
There are seven main types of polyols. Each of these has a specific code, or E-number in Europe, which shows that they are safe for humans to consume. Below, we discuss the differences between each type of polyol.
1. Erythritol (E968)
Erythritol is 60-80% as sweet as table sugar, and contains no calories (1). It's found naturally in small amounts in some fermented foods such as miso and soy sauce, but it's more commonly found in food products as an added sweetener (3). For more information, check out Is Erythritol a Healthy Sugar Alternative? The Lazy Person's Guide .
2. Sorbitol (E420)
Sorbitol is 60% as sweet as table sugar, and contains 2.6 calories per gram (1). This polyol is naturally found in (15) :
- Sweet corn
It's often used as a sweetener in a variety of foods, including sugar-free mints and chewing gum, jam with no added sugar, and mouthwash and toothpaste.
3. Mannitol (E421)
Mannitol is 50-70% as sweet as table sugar, and contains 1.6 calories per gram (1). It's naturally found in certain vegetables, such as mushrooms, cauliflower, and snowpeas (15). This is also used to sweeten sugar-free candy and chewing gum.
4. Xylitol (E967)
Xylitol provides the same level of sweetness as table sugar, but roughly 40% fewer calories (1). It is commonly used as a sweetener in toothpaste and sugar-free chewing gum, candy and mint. It's also found in small amounts in berries, seaweed, yeast and some types of mushrooms (4, 5).
5. Maltitol (E965)
Maltitol is 50-90% as sweet as table sugar, and contains 3 calories per gram (1). It's naturally present in small amounts in some types of fruits and vegetables. Maltitol is often used as a sweetener in "no added sugar" or "diabetic" versions of chocolate, jelly sweets (soft candy) and ice cream. For more information, check out What Is Maltitol and Is It Safe? A Thorough Review for Non-Scientists .
6. Lactitol (E966)
Lactitol is 35-40% as sweet as sugar, and provides 2.4 calories per gram (1). It's a version of lactose that has been hydrogenated in a lab, meaning it's had hydrogen added to it. Lactitol can be found in "no added sugar" chocolate and baked goods.
7. Isomalt (E953)
Isomalt is 45-65% as sweet as sugar and contains 2 calories per gram (1). It's a hydrogenated version of a sugar called isomaltulose, and is often found in "sugar-free" hard candies.
Polyols, FODMAPs and Gut Issues
Summary: The most common polyols found in our diet are: erythritol, sorbitol, mannitol, xylitol, maltitol, lactitol and isomalt. These vary in sweetness, but all contain fewer calories than table sugar. They can be found naturally in certain fruits and vegetables, and are often used as sweeteners in "sugar-free" and "diet" products.
A high intake of polyols can irritate the gut. This is because they aren't absorbed well, and attract water to the intestine. This can lead to bloating, stomach pain and diarrhea in both healthy people and those with IBS (6). In Europe, any product that contains more than 10% of added polyols must warn that "excessive consumption may produce laxative effects" (7).
FODMAPs and Gut Issues
Because polyols are a high FODMAP food, some people who have IBS need to reduce their intake of them. For more information about the low-FODMAP diet, check out this guide.
Effects of Specific Polyols in the Gut
Different polyols can affect the gut in different ways. Sorbitol and mannitol usually cause the most issues, as they can fuel the bacteria in the large intestine. This creates gas, which often worsens pain and bloating for those with IBS (2). Because sorbitol, mannitol and lactitol have such a strong laxative effect, they are sometimes used to treat constipation. Out of all polyols, xyltiol and erythitol are thought to be the least irritating to the gut (8). But some polyols are linked with good gut health. For example, lactitol and isomalt are also thought to be prebiotics because they feed healthy bacteria in the gut (bifidobacteria) (6). More studies are needed to look into effects of polyols in individuals with and without IBS (6).
Polyols and Weight Loss
Summary: Consuming large amounts of polyols, especially sorbitol and mannitol, can lead to stomach pain, bloating and diarrhea. They can also have strong laxative effects.
For those with a sweet tooth, using polyols in place of sugar will help reduce your caloric intake, which can promote a small amount of weight loss (9, 10, 11). However, some people worry that replacing sugar with sweeteners like polyols may harm weight loss efforts by interfering with appetite or metabolism. But there is no direct evidence in humans to support this concern. With the exception of erythritol, polyols still contain some calories, so consuming large amounts of them can still lead to excess calories (as well as possible gut issues, as described above). That said, one small change in your diet will rarely make a big difference in your weight. Creating a number of long-term healthy habits is crucial for losing weight. For evidence-based weight loss tips, check out these 77 Proven Ways To Lose Weight And Keep It Off.
Polyols and Blood Sugar Levels
Summary: Along with a healthy diet and lifestyle, using polyols to replace sugar can help you reduce your caloric intake and support weight loss, especially if you have a sweet tooth.
The polyols listed above can reduce spikes in blood sugar when compared to sugary food and drinks (7). This is because most polyols have little to no effect on blood sugar levels (12). To go along with these findings, studies in people with type 2 diabetes have found improvements in average blood sugar levels when sugar is replaced with polyols (12). However, maltitol can increase blood sugar at a higher level than other types of polyols (12). This is important to be aware of because maltitol is often used in "diabetic" chocolate and "diabetic" sweets. This is why these "diabetic" products usually aren't recommended by health professionals. Such products can also be high in fat and calories, and may cause gut problems for some people. For those who count carbs, it can be tricky to figure out how to account for polyols. This is because the amount of carbohydrates we absorb from polyols can vary. If you're unsure about this, it's always best to speak to a healthcare professional for individual advice.
Polyols and Dental Health
Summary: Replacing sugar with polyols can help stabilize blood sugar levels. However, maltitol, often found in "diabetic" food, increases blood sugar more than other polyols, so you'll want to avoid such products.
There is good evidence that replacing sugar with any of the seven polyols listed above can be good for your teeth (7). Sugar feeds the bacteria in the mouth. This bacteria then release acids, causing tooth decay. But this doesn't happen when we consume polyols. Instead, our teeth can stay strong or 'mineralized' (7, 13). Most of the evidence to back this up is related to xylitol, sorbitol and erythritol. Out of these, some studies have found that erythritol is the most effective at reducing the risk of dental caries (13, 14). This is why products like toothpaste and mouthwash include these types of polyols.
Should You Include Polyols in Your Diet?
Summary: Several studies have found that replacing sugar with polyols can protect your teeth. This is why you may find polyols in your toothpaste or mouthwash.
Polyols are low-calorie sweeteners made from carbohydrates. They are often found in "sugar-free" and "diet" products, and also occur naturally in certain fruits and vegetables. Polyols vary in sweetness and calorie count, but they all contain fewer calories than ordinary table sugar. Replacing sugar with polyols has been shown to support weight loss, stabilize blood sugar levels and protect the enamel on our teeth. But polyols are high-FODMAP foods, which can irritate the gut depending on how much is consumed and how sensitive your gut is. As with all food, the type and amount of polyols consumed makes a difference in how it may affect your body. For example, maltitol increases blood sugar levels more than erythritol does, while sorbitol can be more irritating to the gut than xylitol. In general, polyols can be a helpful way of reducing sugar intake—unless they cause you stomach problems.