How should I count net carbs and sugar alcohols?
"Net carbs" usually means total carbohydrate minus fiber, and sometimes minus some or all sugar alcohols. That can be useful for certain labels, low-carb diets, or blood-glucose management, but keep in mind that different fibers and sugar alcohols have different energy values, absorption patterns, blood-glucose effects, and digestive consequences.
For body-composition tracking, do not treat net carbs as a loophole. If a food has calories, those calories still matter for calorie balance, even if the label makes the carbohydrate count look smaller. A protein bar with fiber syrup and sugar alcohols may be easier to fit than a candy bar, but it is not free food.
The cleanest method is consistency. Use the nutrition label or your tracking source the same way each time, rather than trying to outsmart every ingredient. If your tracking method counts sugar alcohols as carbohydrate, leave them counted unless you have a specific reason and a consistent method for adjusting them. Randomly subtracting them sometimes and counting them other times creates more error than precision.
Watch tolerance. Large amounts of sugar alcohols, especially from protein bars, low-carb desserts, and sugar-free candy, can cause gas, bloating, cramping, or diarrhea. The effect depends on the specific sugar alcohol and your personal tolerance. A food that technically fits the macros but ruins digestion is not a good default.
Most people should focus on the major levers: Count the food consistently, pay attention to calories, watch digestion, and do not let "net carbs" turn highly engineered snack foods into a pretend free pass.