Pleas help me clear up this expression about "supplement" Please help me confirm whether the following terms are natural and easy to understand. Health Supplement Food Supplement When I describe the pills we take regularly or some kinds of special food we eat in order to improve our health, are they appropriate and frequently used? Aside from these expressions, are there any other words meaning the same thing? Formal ones or colliquial ones. My sencond question: Could you list any common and well-known this kind of things you got know for me? Thank you.