Chlorella is a single-celled, freshwater alga, native to Taiwan and Japan, that is naturally rich in proteins, vitamins, minerals, and dietary fiber. Its reported benefits include boosting antibody count, promoting weight-loss, and fighting cancer and other diseases. There are various types of chlorella, each with different nutritional qualities. Those most commonly sold as food supplements are believed to have the highest nutritional value. Supplements are available as tablets, powder, or liquid extracts. Chlorella's tough cell wall makes it rigid and impossible to digest in its natural form. It is processed before being sold so its nutrients can be properly digested.