Mostly though, a type of yeast is added to glucose or to starch to manufacture the sweeteners on a large scale for use in candy bars, chewing gums and soft drinks. Some polyols are also available in powdered form and sold in sachets. 

Don't confuse them with regular alcohol such as beer and wine: although the name may be misleading, the 'alcohol' part simply refers to the hydroxyl compounds that are used to produce the sweeteners. The term 'polyol' refers to the presence of multiple OH-groups in the chemical structure.

They have a number of advantages: most of them are stable under high temperatures and are soluble in water as well, so they are god for your favorite recipes. And they prevent the bacteria that form dental plaque from adhering to your teeth, which is why polyols are such a popular ingredient in chewing gum and toothpaste. 

Sugar alcohols have roughly the same amount of sweetness as sugar, but they are less metabolized by the body and are thus often recommended to diabetics because of their low glycemic index. They aren't really ideal for dieting though, as they still contain a fair amount of calories. Compared to the side effects caused by sugar though, polyols are regarded as a relatively safe bet, despite the minor discomforts they may carry.

The low absorption rate of polyols by the blood stream can lead them to ferment in the stomach or intestines, which in turn leads to the discomfort you might feel from them. The maximum daily intake of most sugar alcohols is 35 to 50 grams. 

Not every person reacts the same to this type of sweetener, but if you're sensitive to yeast or regularly experience bloating from eating fruit, you may want to look for another natural solution, such as stevia, which has no side effects at all.