This appears in this month's issue of Outside Magazine. It seems to be a well-informed answer to an oft-asked question.

http://outside.away.com/outside/bod...s_20040406.html

What are "net carbs"?

Net carbs are mashed potatoes, creamed corn…basically anything served by a person wearing a hair net. Just kidding—for the growing phenomenon of the phrase "net carbs" on labels dotting your grocery store aisles, you can thank the teeming hordes currently on some form of low-carbohydrate diet.

The people at Atkins and elsewhere say that net carbs are the total number of carbohydrate grams in a "low carb" food product, minus the grams of those carbohydrates that cause little to no elevation in your blood-sugar level. The entire diet, you will recall, is based on the idea of releasing people from the cycle of blood-sugar spikes and an ensuing insulin-mediated storage of dietary carbohydrates as fat.

Because fiber is a carbohydrate that merely tips its hat at your lower intestine, they subtract grams of fiber from the total number of carbohydrate grams. Fair enough—even if you do have to search the prepared product aisles with bomb-sniffing dogs to find foods containing more than a scrap of fiber. Another carbohydrate form known as sugar alcohol (anything on the label ending in -tol or -ol) is also believed to cause only a minimal rise in blood sugar, so food makers exclude those from their net carb calculations as well. The carbohydrates polydextrose, and glycerin (an ingredient most commonly found in soap) are also excluded, for the same reason.

Critics of this new math say that all of the above are still carbs, and any carbs ingested in an environment of elevated blood sugar will be stored as fat whether or not those carbs were guilty of raising the blood sugar themselves.

The FDA is looking into the entire low-carb labeling question, including the net carbs claim. And the Center for Science in the Public Interest recently complained about "net carbs" labeling, portending a future where the nutrition facts label becomes "a zoo of competing numbers." Think of the entire debate as part of a vocabulary which makes us slaves to the food-approval issuances of a cardiologist-turned-branding giant. Consider that it has been used to sell the world a low-carb peanut butter cup.