Chlorella has gained recognition as a popular “superfood” due to its rich nutritional profile. Many individuals, especially those following plant-based diets, are interested in whether this green algae can serve as a reliable source of vitamin B12. This article explores chlorella’s composition and the scientific evidence regarding its vitamin B12 content and bioavailability for human consumption.
Understanding Chlorella
Chlorella is a single-celled green algae that thrives in fresh water environments. This algae is cultivated globally and valued for its dense nutritional content.
Chlorella is a “superfood” rich in protein, chlorophyll, various vitamins, and minerals. Common species used in supplements are Chlorella vulgaris and Chlorella pyrenoidosa. Chlorella pyrenoidosa may have higher concentrations of B12 and amino acids than Chlorella vulgaris.
Chlorella’s B12 Content and Bioavailability
Chlorella contains various forms of vitamin B12, including active forms like methylcobalamin and adenosylcobalamin, as well as inactive forms often referred to as pseudovitamin B12. Methylcobalamin, a biologically active form of B12, has been identified and characterized in Chlorella vulgaris. The presence of both active and inactive forms has led to scientific discussions regarding its effectiveness as a B12 source.
Research indicates that some chlorella strains can provide bioavailable vitamin B12 for humans, particularly for vegans and vegetarians. One study involving B12-deficient vegans and vegetarians showed that daily supplementation with Chlorella pyrenoidosa led to a significant decrease in serum methylmalonic acid (MMA) levels, a marker for B12 deficiency. Serum homocysteine levels also decreased, and serum B12 levels increased in most participants.
While these findings suggest chlorella’s potential as a B12 source, not all chlorella products contain sufficient amounts of bioavailable B12. The cultivation method can influence B12 content; chlorella grown under natural light in controlled environments, where bacteria can symbiotically produce B12, is more likely to contain this vitamin. In contrast, chlorella cultivated in fermenters or bioreactors may not contain B12.
Practical Considerations for Chlorella Supplementation
When using chlorella for vitamin B12, select a high-quality product. Chlorella has a tough outer cell wall that can hinder nutrient absorption in the human digestive system. Many supplements undergo processing to break or crack this cell wall, enhancing nutrient bioavailability. This “cracked cell wall” chlorella improves nutrient access.
Chlorella is commonly available in powder or tablet forms. Dosages can vary, but some products suggest that a daily intake of approximately 3 to 4 grams of chlorella can provide about 96-120% of the recommended daily amount of vitamin B12 for an adult, which is around 2.4 micrograms per day. For example, some organic chlorella powders are reported to contain 60 micrograms of B12 per 100 grams.
It is advisable to consult a healthcare professional before beginning chlorella supplementation, especially for individuals with existing B12 deficiencies or specific dietary requirements. Monitoring B12 levels through blood tests, such as serum methylmalonic acid (MMA) and homocysteine levels, provides a more accurate assessment of B12 status than serum B12 alone. While chlorella can be a helpful addition, combining it with other B12 sources or a B12 supplement might be a sensible approach to ensure adequate intake, particularly for those with absorption difficulties.