Sugar Alcohols: What Should I Know?

Have you ever wondered how sugar-free foods still manage to taste delightfully sweet? Sugar alcohol is often the answer.

With the demand for low-carb foods and beverages on the rise, the sugar alcohol market is expected to surpass US$ 4.59 billion by 2033 — but what makes these sugar substitutes so sweet?

What is Sugar Alcohol?

Sugar alcohols – also known as polyols – are widely used as sugar substitutes. They differ from ethanol — the type of alcohol found in spirits — but are still categorized as alcohols due to their chemical makeup.

In chemistry, alcohols are compounds containing carbon and a hydroxyl molecule (made of hydrogen and oxygen). Sugar alcohols are sugar molecules with multiple hydroxyl groups attached to their carbon molecules.

Unlike table sugar, sugar alcohols offer the benefit of having fewer calories, making them increasingly popular, especially in sugar-free snacks.

The human body isn’t able to metabolize most sugar alcohols, resulting in lower overall calorie absorption. However, this can sometimes lead to unpleasant side effects.

These effects occur due to the fermentation of sugar alcohols by gut bacteria in the colon, a process that produces gas and draws water into the gut, especially when consumed in excess — more on this later.

What are the Uses of Sugar Alcohols?

Sugar alcohols are multifunctional, and are often used for sweetening foods, enhancing dental health, and treating constipation.

In oral care, they are key ingredients in chewing gum for preventing dental cavities. Additionally, in critical medical situations, sugar alcohols play a significant role.

For instance, mannitol, a specific type of sugar alcohol, is FDA-approved for intravenous use (administered via the vein) to reduce brain swelling in patients with severe conditions like brain tumors and infections.

What are the Different Types of Sugar Alcohols?

Sugar alcohols are commonly found in beverages and food products labeled as "sugar-free," "zero sugar," or "no added sugar."

While these labels indicate the absence of regular sugar, the majority of these products contain sugar alcohols.

When a product claims to be sugar-free or to have no added sugar, manufacturers are required to specify the type and amount of sugar alcohol used, measured in grams, on the label.

If multiple other sugar alcohols are present, they're often included under the ‘total carbohydrates’ section. Some of the most common sugar alcohols are:

• Maltitol
• Xylitol
• Erythritol
• Lactitol
• Isomalt
• Sorbitol
• Mannitol

Are Sugar Alcohols Bad for You?

Most sugar alcohols are recognized for their low calories and minimal impact on blood sugar levels, making them popular food additives and sugar substitutes in the food industry.

While comprehensive research on the long-term health effects is still evolving, it's clear that excessive consumption of table sugar can lead to potentially detrimental health outcomes, including substantial weight gain and type 2 diabetes.

Sugar substitutes can be a strategic way to reduce added sugar intake, which is particularly beneficial for people with diabetes struggling with sugar cravings.

Healthcare providers often emphasize avoiding added sugars and maintaining a healthy lifestyle, but seldom provide practical solutions to overcome a sweet tooth.

In addiction medicine, harm reduction therapy for drug use often involves prescribing smaller amounts or different kinds of drugs to minimize harm to the body, acknowledging that completely stopping drug use can be challenging. This approach reduces the chance of relapsing, limiting potential harm.

Similarly, while the long-term benefits and side effects of sugar substitutes aren’t fully understood, they offer a potentially safer way to satisfy the "need for sweet" while reducing the harm associated with added sugar. These substitutes are also deemed safe for use by the FDA.

What are the side effects of sugar alcohols?

Below are some of the side effects you can expect when you don’t use artificial sweeteners responsibly:

Digestive issues

Unlike sugar, sugar alcohols are generally poorly absorbed by our digestive system, often being excreted unchanged, which helps in minimizing weight gain from their consumption.

Ideally, these sugar alcohols would pass through our system without alteration.

However, in reality, they’re partially digested by natural bacteria in our colons. This happens through fermentation, resulting in gas and bloating.

The residual sugar alcohols then induce osmosis, pulling water into our gut, leading to watery and poorly-formed stools.

Laxative effect

As previously noted, sugar alcohols are partially metabolized by gut bacteria, causing water to be drawn into the gut.

This increase in water absorption aids the movement of substances through the gut, but in excess, it can result in diarrhea.

Although it can sometimes cause an upset stomach, this laxative effect is utilized by pharmaceutical companies to help with constipation relief. In fact, certain sugar alcohols — like lactitol — are specifically marketed for their laxative properties.

A note on overconsumption of sugar alcohols

Extensive studies have been conducted on popular sugar alcohols to determine the typical amounts that may lead to side effects.

However, these are general guidelines, and individual reactions can vary.

If you start to experience any of the abovementioned side effects — like abdominal pain, bloating, or gas — it might be time to cut back on the sugar substitutes or speak to your doctor about an alternative sweetener.

What are the Benefits of Sugar Alcohols?

Sugar alcohols offer a range of benefits, making them a popular choice in various products.

Weight loss

Sugar alcohols, frequently used as artificial sweeteners, offer a lower-calorie alternative to sugar, with fewer calories per gram. This reduced calorie content can be beneficial in supporting weight loss efforts.

Dental health

Sugar alcohols are often used in mouthwash, toothpaste, and other dental products, as they possess anti-cariogenic properties — meaning they help prevent tooth decay. They achieve this by slowing the growth of plaque-forming bacteria and inhibiting lactic acid production, thereby reducing the risk of dental cavities.

Satisfying sugar cravings

Sugar alcohols vary in sweetness compared to regular sugar, providing a range of sweetening effects that can effectively satisfy sugar cravings. For example, lactitol's sweetness is about 30–40% that of sugar, while Xylitol ranges from 80–100%, offering diverse options for those looking to reduce sugar intake.

Diabetic-friendly sweetener

Sugar alcohols present a suitable alternative to sugar in snacks and various foods for those with diabetes, as they have a less significant impact on blood sugar levels than regular sugar.

How Do Sugar Alcohols Work?

To understand how sugar alcohols function, you first need to understand how sugar works:

Gustatory receptors, or taste receptors, are activated by sugar in the mouth, sending signals to the brain that something sweet is being consumed. These receptors are essential for humans to identify what is nutritious and what could potentially be toxic.

When sugar is eaten, it alerts the brain to the presence of an energy-rich carbohydrate, enhancing the appetite for sweets and stimulating reward pathways. Artificial sweeteners, including sugar alcohols, differ in this respect.

Sugar alcohols vs. regular sugar

While they activate the same taste receptors as regular sugar and produce a similar taste sensation, sugar alcohols don’t provide the energy the body expects when tasting sugar. This difference is significant, since sugar alcohols contain about half the calories of table sugar.

Regular sugar consumption introduces a substantial amount of calories, which can cause weight gain.

Some studies suggest that, as weight increases, sensitivity to sugar decreases, leading to more intense sugar cravings and a cycle of continuous craving and weight gain — this may explain the strong correlation between sugar consumption and obesity.

Substituting sugar with low-calorie alternatives might seem like a viable solution to break this cycle.

However, early research, including a study at Yale, indicates that sugar substitutes might not stimulate the reward pathways as effectively as sugar, possibly leading to a future preference for ‘real’ sugar.

It's also important to note that sweeteners, including sugar alcohols, still contain some calories.

The mechanism of sugar alcohols is unique in that they’re either excreted from the body completely, without contributing to energy reserves, or only have a minimal impact. This is significant, because energy that the body doesn’t use is typically stored as fat.

Food manufacturers often use these sugar substitutes to replicate the sweetness of sugar while reducing the calories in their products.

The table below illustrates the differences between regular sugar and sugar alcohols:

How Do I Choose the Best Sugar Substitute?

When selecting the ideal sugar alcohol, it's wise to strike a balance between calorie content and sweetness.

Avoid choosing solely based on lower calories, as insufficient sweetness might lead to increased consumption. Erythritol and maltitol are good starting points.

Erythritol offers zero calories with 60–70% of the sweetness of regular sugar, while maltitol contains more calories but is sweeter than erythritol.

Additionally, consider your tolerance to new substances, as some sugar alcohols may cause gastrointestinal symptoms and discomfort.

The table below compares the most popular sugar substitutes and may help you decide which one would suit your preferences:

How do I interpret the GI value of a sugar alcohol?

The number in the glycemic index (GI) represents how quickly a food raises blood sugar levels compared to pure glucose. Glucose is given a GI value of 100, serving as the reference point. Other foods are then measured against this:

• Low GI: 55 or less
• Medium GI: 56 to 69
• High GI: 70 or higher Based on this, all the above listed sugar substitutes are viable options, with erythritol standing out as the top choice.

Where Can I Get More Advice on Sugar Alcohols and Other Low-Calorie Sweeteners?

Are you considering switching from table sugar to a low-calorie sweetener? LifeMD can help you decide which one is right for your needs.

LifeMD can connect you to a team of healthcare professionals who can provide guidance on sugar substitutes and talk you through the available options — whether you’re trying to lose weight, manage diabetes, or simply make better choices for your dental health.

Book your appointment today to get started.