By necessity, people with diabetes become great label-readers and grocery-store shelf-watchers, always on the lookout for tasty food that won’t cause blood glucose levels to spike.

In your recent travels at the supermarket, you may have noticed a new class of zero-calorie products getting some shelf space. Maybe it was a bright-colored soda line called Zevia, or a sugar substitute called Truvia. You pick up a product and see an ingredients list that includes something called either “Rebaudioside A”, or “Reb A”, and maybe a mention of something on the box called “stevia”. The product probably claims it is a zero-calorie or low-calorie sweetener with few, if any, carbs and which doesn’t raise blood glucose levels. You hesitate. Too good to be true?