If you are concerned about staying healthy, check your steamer's construction to see if any plastics have been used. You will want to know particularly if the steamer basket tiers are made from plastic. The recycling number should be on them if they are. Plastics that are #7 are likely to be polycarbonate plastics. This means they can leach BPA into food when they are steamed. The quantity leached by just steaming is much lower than by boiling but it's a good idea to eliminate the risk completely because BPAs are endocrine disruptors. If you want to buy an automatic food steamer, make sure that all parts that will come in contact with food are BPA-free.