Chlorella is a single-celled freshwater microalgae that is rich in complete protein, iron, vitamin A, vitamin C, B Complex vitamins, calcium, magnesium, iron, phosphorous, zinc, antioxidants, amino acids, and essential fatty acids. It’s one of the richest known sources of chlorophyll, the sunlight-collecting molecule in plants that gives them their green pigment. The cell wall of chlorella must be broken down before its nutrients can be digested, thus the term "broken cell wall" or "cracked cell wall" is important to look for when purchasing Chlorella supplements. Chlorella contains what is known as Chlorella Growth Factor (CGF). CGF is believed to be responsible for chlorella’s unique nutritional profile. CGF is produced by Chlorella during intense photosynthesis, in which chlorella multiplies four times every 20 hours. CGF contains amino acids. peptides, proteins, vitamins, sugars and nucleic acids. The high amount of chlorophyll found in Chlorella helps build red blood cells and thus increases oxygen availability. Chlorella contains high amounts of Lutein, an antioxidant carotenoid that is especially beneficial for eye health and vision.