Xylitol is a very popular alternative to sugar and is a common ingredient in sugar-free or low-sugar products like candies, mints, chocolates, drink mixes, dental-care products and also in supplements like protein supplements and sports drinks. They are also sold in the pure form as white crystals that look like sugar. Xylitol is as sweet as sugar but has less calories and is much loved by product developers. However, at Bioteen we decided to not use it in any of our formulations for the reasons given in this article.

XYLITOL BASICS

Xylitol belongs to a group of carbohydrates called sugar alcohols because its structure resembles that of a sugar and an alcohol. This unique structure confers an interesting property to it, namely the ability to stimulate the sweet receptors on the tongue without providing the calories that regular sugars provide. 

Besides its nutritional qualities and sensory properties, xylitol is highly appealing as it is naturally present in birch wood (pictured here). Birch wood is rich in xylans which are extracted and broken down to xylose. The latter is converted by means of an enzymatic reaction to xylitol.

Xylitol is not at all the same alcohol that gets you drunk (ethanol) and eats away the liver in excess. It is thus safe for those with alcohol addictions.

Xylitol has been around since the late 1800s and was used as a sweetener during World War 1 in Scandinavia due too a shortage of sugar. However, it rose to prominence only about 10 years ago thanks to the rise in popularity of calorie and carbohydrate-restricted diets.

Xylitol provides far less calories (40% less) than sugar and provides the same level of sweetness.

• 1 teaspoon of table sugar= approx. 4g= 16 calories

• 1 teaspoon of xylitol=approx. 4g= 9.6 calories

• Sweetness of 1 teaspoon of xylitol= sweetness of 1 teaspoon of sugar

Xylitol is also much loved because it can be promoted as a natural sweetener thanks to its natural occurrence in many fruits and vegetables and its production using fermentative techniques using enzymes.

Xylitol also has interesting medical applications in products that treat constipation and food or oral-hygiene products to fight dental caries, as xylitol inhibits the growth of bacteria that cause enamel erosion and gum disease [1].

Xylitol is also a sweetener of choice in diabetic products because it does not increase blood sugar as high as sugar following its consumption.

Xylitol is in almost everything: from mints, chewing gums, oral hygiene products and even medical products.

However, although xylitol seems to be a healthier alternative to sugar we chose to steer clear of it in TeenActive™ for the following reasons:

Xylitol can easily cause intestinal distress

Glucose and other sugars are rapidly absorbed in the upper part of the intestines. Xylitol, on the other hand, is very slowly absorbed in the upper part of the small intestines for lack of an efficient transport mechanism.

This causes xylitol to reach the lower part of the small intestines and the colon where it increases the chance, depending on how much you’ve consumed of course, of getting diarrhoea. This diarrhoea is more precisely known as osmotic diarrhoea and is generally caused by unabsorbed or slowly-absorbed food elements which interferes with the absorption of water in the intestines. This results in softer stools and runny tummies.

The slow and inefficient absorption of xylitol also means that the resident intestinal bacteria also has time to break it down via fermentation, giving rise to gas and bloating. The combination of osmotic diarrhoea and gas can be an explosive one!

The main problem with xylitol is how little it takes to start giving side effects. Research has established this amount at 0.3g Xylitol per kilogram of bodyweight (0.3g/ kg), which means that it takes only 18g of xylitol to start giving a 60kg teenager trouble.

If we were to use Xylitol in TeenActive we would have to use about 15g to sweeten a shake or sports drink serving if this is the only sweetener we used or 10g if used in combination with another sweetener (e.g. Stevia). The amounts of xylitol could easily add up if back-to-back servings are consumed (e.g. a Hydrofuel followed by Recovery Shake).

Xylitol is not pet friendly

A key reason why we don’t use Xylitol in TeenActive is because of its proven toxicity in dogs.

Contrary to humans, when dogs consume xylitol their bodies produce large amounts of insulin. This leads to the cells of dog absorbing large quantities of glucose from the blood, leading to dangerously low blood sugar level. Xylitol may also have a negative effect on the liver of dogs and can cause liver failure [2].

Another alarming factor is that it takes only a tiny amount of xylitol to affect a dog, like 0.1 grams per kg of body weight for a dog. Therefore, a small 3kg dog can get sick from just 300mg grams of xylitol. Scary, if you realise that 1 small mint contains at least 500mg of xylitol and that xylitol is so many products nowadays, even peanut butters.

It takes only 300mg of Xylitol to cause severe hypoglycaemia in a 3kg dog. It is important to read labels carefully before giving anything to dogs. 

Most companies selling xylitol or xylitol-containing products include a disclaimer but in our opinion these are not sufficiently emphasized because putting a big warning about toxicity to dogs doesn’t look good for a product that’s supposed to be natural and safe.

If you are a dog owner, be warned, about xylitol and keep it out of reach of your pet dogs. It can help to inform kids and visitors sufficiently about not giving food to dogs.  If you believe that your dog has accidentally ingested xylitol, take it to your vet immediately.

Most xylitol products will carry warnings about it being not being a pet friendly products, usually in fine print or by means of a small logo on the back label. We feel that these warnings need to be more prominent.

References

  1. Nayak AP et al. The effect of xylitol on dental caries and oral flora. Clin Cosmet Investig Dent. 2014; 6: 89–94.2
  2. Schmid RD and Hovda LR. Acute Hepatic Failure in a Dog after Xylitol Ingestion. Journal of Medical Toxicology: Official Journal of the American College of Medical Toxicology, 01 Jun 2016, 12(2):201-205