I've used them and they work...Main problem with them is they have gastric side effects (constipation, gas, etc...) I don't use them too often, because I don't like farting every 10 minutes and not being able to #2. That said...I use them when I'm in a sitaution where cheating is inevidible (Family Reunions, Holiday Meal w. Family, etc...) BTW, they only block something like 60-75% of Starch...and they don't block Sugars at all. So, when I use them, I also avoid all fruit.