There are products that seems to be healthy indicating zero calorie/carb/fat/cholesterol on the label but contains possibly dangerous substance(s). One such product is the SureBuy Stevia Powder from Rustan Supermarket. While stevia leaves extract are generally safe, another ingredient may pose risks to certain individuals.
Maltodextrin has a high glycemic index and can spike the blood sugar making it dangerous to diabetics. Also, it has been linked to an increase in the incidence of Crohn's disease in one study.
While the label maybe right to claim that stevia is a healthy substitute to sugar and is completely natural, maltodextrin may be the opposite. Maltodextrin can be produced from genetically modified corn making it unnatural.