Chlorella is a genus of single-cell green algae that is spherical in shape, about 2 to 10 microns in diameter and without flagella. Through photosynthesis, Chlorella multiplies rapidly, requiring only carbon dioxide, water, sunlight and a small amount of minerals to reproduce.
Many people believed Chlorella could serve as a potential source of food and energy because it is high in protein and other essential nutrients. When dried it is about 45% protein, 20% fat, 20% carbohydrate, 5% fiber and 10% minerals and vitamins.
Following fears of an uncontrollable population boom, during the late 1940s and the early 1950s Chlorella was seen as a new and promising food source and a possible solution to the then-current world hunger crisis. Since the growing world food problem of the 1940s was solved by better crop efficiency and not from a "super food," Chlorella has not seen the kind of public and scientific interest that it had in the 1940s, but it can still be found today from companies promoting its "super-food" effects.