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Glycerol (also known as glycerin or glycerine) is a colorless, odorless, sweet tasting nutrient. It is technically a trihydroxy alcohol found naturally as the backbone of triglycerides in the body.  It is added to protein bars to help make them moist and also to sweeten them.  It does not cause any significant blood sugar response when taken as part of protein bar and seems to be eliminated from the body mostly unused.  Glycerol is an interesting compound that has been shown to enhance athletic performance and cause “hyperhydration” when consumed with water (above and beyond that with water alone).  It seems to help keep the body cooler during exercise.  Glycerol does contain 4.32 calories per gram. 

The question on everyone’s minds recently has been “how many carbohydrates are actually in my protein bar?” This question has not only been raised by consumers but also the FDA who has now forced manufacturers to label glycerol and other sugar alcohols in protein bars as carbohydrates even though they do not act like carbs in the body.  That is why the nutritional labels of protein bars have changed and you can see that carbohydrate content has shot up drastically with these new regulations. Of course, you’ll also see terms like “net impact” carbs or “unavailable” carbs on the label as well with some sort of fancy chart explaining it all.  Manufacturers are listing these to educate consumers about the type of nutrients in the bars and their little to no impact on blood sugar levels.  The FDA defines glycerol as a carbohydrate by process of elimination.  That is, when a bar is analyzed anything that is not protein, fat, moisture, and ash is considered a carbohydrate.  This philosophy is strongly disagreed upon by supplement manufacturers who contend that since glycerol is only partially absorbed and does not act like a carbohydrate in the body, it should not be listed as such.

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