Xylitol, sorbitol, and mannitol are all artificial sweeteners that are called sugar alcohols or polyols. They are helpful for those trying to control the amount of calories in their diet and also for diabetics. Read on to learn more about these artificial sweeteners and whether they are safe, and what role they play in weight loss.
Xylitol is a sugar alcohol that is used as a sugar substitute. It occurs naturally and it is found in the fibrous vegetables and fruit, as well as in corn cobs and various hardwood trees such as birch. In fact, it is produced naturally in our bodies. It is roughly as sweet as sucrose but only has two thirds of the energy. One teaspoon of xylitol contains 9.6 calories, while one teaspoon of sugar contains 15 calories. There are zero net effective carbohydrates in xylitol while sugar has 4 grams per teaspoon. Xylitol is safe for diabetics as it has less impact on blood sugar levels than regular sugars do. It has a GI of 7, while sugar has a GI of 100. It is used in cooking, baking, in beverages, chewing gum, mints, and other products such as nasal and mouth washes.
Xylitol is safe for teeth as it does not encourage tooth decay, and may actively aid in repairing minor cavities. Research has confirmed that plaque is reduced when xylitol is consumed as it attracts and then starves harmful micro-organisms allowing the mouth to re-mineralise damaged teeth with less interruption. Xylitol does not contribute to high blood sugar levels or the resulting hyperglycaemia caused by insufficient insulin response. It may also have potential as a treatment for osteoporosis. Xylitol-based chewing gum can help to prevent ear infections as the act of chewing and swallowing helps with the disposal of earwax and clearing the middle ear, while the xylitol prevents the growth of bacteria in the Eustachian tubes.
Xylitol may help to control oral infections of candida yeast. It is safe for pregnant and nursing women and regular use can significantly reduce the probability of transmitting bacteria that is responsible for tooth decay from mother to child during the first two years of life by as much as 80 percent.
However, xylitol, like most sugar alcohols, can have a laxative effect as it is not fully broken down during digestion. It has no known toxicity.
Sorbitol, also known as glucitol, is a sugar alcohol that is slowly metabolised by the body. It is mainly used in sugar free mints and various cough syrups, and is usually listed under the inactive ingredients. It is also used in diet foods, and sugar-free chewing gum. Sorbitol also occurs naturally in many stone fruits and berries from trees of the Sorbus genus. It is known as a nutritive sweetener as it gives 11 kilojoules of energy per gram as opposed to the 17 kilojoules of energy per gram of sugar and starch. It is about sixty percent as sweet as sucrose with one third fewer calories. It does not promote tooth decay and is helpful for people with diabetes.
Consuming large amounts of sorbitol can lead to abdominal pain, gas, and mild to severe diarrhea. It can also aggravate irritable bowel syndrome and fructose malabsorption.
Mannitol is a polyol or sugar alcohol that was originally isolated from the secretions of the Flowering Ash, called Manna after their resemblance to the biblical food. Chemically, it is similar to xylitol and sorbitol. Mannitol is used as a sweetener for people with diabetes, and is commonly used as a sweetener in breath freshening candies as it has a cooling effect. It is about 50 percent as sweet as sucrose. It does not promote tooth decay and has a low caloric content. Mannitol does not pick up moisture and for this reason it is often used as a dusting powder for chewing gum. Due to its high melting point, it is also used in chocolate-flavoured coating agents for ice cream and sweets.
Artificial Sweeteners and Weight Loss
Xylitol, sorbitol, and mannitol are all sugar alcohols that have a lower caloric value than sugars. In this way, they can help people to achieve their weight goals. They are incompletely absorbed by the body and what is absorbed is metabolised by insulin-independent mechanisms or excreted via the urine. A significant amount of what is not absorbed is metabolised to short chain fatty acids and gases in the large intestine. Xylitol has 2.4 calories per gram; sorbitol 2.6 calories per gram; and mannitol 1.6 calories per gram. This is compared to the traditional 4 calories per gram that sugar has. All sugar alcohols have a low GI, and they can be used to completely or partially replace traditional sugars such as sucrose and glucose. This helps to reduce the overall glycaemic load of the diet, thus assisting with weight loss.
However, some studies have shown that products that contain artificial sweeteners can actually help to promote weight gain. The theory is that when the body tastes sweetness, it prepares itself for a calorie load. If the sweetness occurs without the related calories, such as when artificial sweeteners are used, we either keep on eating or reduce our calorie-burning metabolic activity. It is currently recommended that foods and drinks that contain artificial sweeteners be used in moderation. Do not use them as an excuse to indulge in other high calorie foods or to skip physical activity that is important to weight control and health.