Erythritol is found naturally in some foods. It's also made when things like wine, beer, and cheese ferment.

Besides its natural form, erythritol has also been a man-made sweetener since 1990. You can find it with other sugar substitutes in stores and online.

Calories. Sugar has 4 calories per gram, but erythritol has zero. That's because your small intestine absorbs it quickly and gets it out of your body through urine within 24 hours. This means erythritol doesn't have a chance to "metabolize" -- turn into energy in your body.

Safety. Though erythritol is one of the newer sugar alcohols on the market -- xylitol and mannitol have been around longer -- researchers have done several studies of it in animals and humans. The World Health Organization (WHO) approved erythritol in 1999, and the FDA did the same in 2001.

How much can I eat? There aren't official guidelines on using erythritol, but most people can handle 1 gram for every kilogram of body weight daily. So if you weigh 150 pounds, you can tolerate 68 grams of erythritol a day or more than 13 teaspoons.

How it's used. You can use erythritol the same way as sugar. It's fine to stir it into your coffee or tea, sprinkle it on grapefruit, or bake with it. Remember that it's a sugar substitute and not real sugar, so foods that you bake may have a different taste or consistency than you're used to.

Side effects. Eating lots of sugar alcohols can lead to bloating and an upset stomach. Some sugar alcohols can cause gas and cramping or work like a laxative when they reach your colon. But erythritol is generally mostly absorbed before it gets to your colon and is excreted unchanged in your urine. Excess gas and a laxative effect are possible, but people generally handle it better than other sugar alcohols, and it doesn't come with any warnings.

OK for your teeth. In most cases, bacteria in your mouth break down regular sugars and starches and turn them into acid. This can wear down your enamel and cause cavities. But the FDA says erythritol is good for oral health because it slows the growth of one type of bacteria and decreases the acid that bacteria make.