Are chemicals harmful or beneficial to humans?

The human body is 100% chemicals. The food we eat is 100% chemicals. What we drink, be it water or Scotch whisky, is 100% chemicals. The drugs we take, illegal or prescribed, are 100% chemicals. The air we breathe is 100% chemicals. The Earth we live on is 100% chemicals. The TV you watch is 100% chemicals. The sofa you sit on is 100% chemicals. Without chemicals the Earth or any life form would not exist.