All living creatures need to eat. Eating a variety of different healthy foods in moderate amounts is important. How do we know which foods are healthy? Researchers can compare the foods consumed by healthy and unhealthy people by asking what and how much they eat. Unfortunately, people cannot always remember what and how much they eat, which makes it difficult to figure out which foods are healthy. Recently, researchers discovered that a group of research tools called omics could help. When people eat, the building blocks of food are broken down into small compounds called metabolites. With laboratory equipment, researchers can measures these metabolites in food and in the body, to help them get a better idea of which foods are healthy or unhealthy. Researchers can also use omics tools to find the best foods for each unique person so that we can all stay healthy and happy.