Spirulina is a group of lower plants belonging to the phylum Cyanobacteria, family Trichoderma. They are the same as bacteria, there is no real nucleus in the cell, so they are also called cyanobacteria. The cell structure of cyanobacteria is primitive and very simple, and it is the earliest photosynthetic organism to appear on Earth, having survived on this planet for 3.5 billion years. It grows in bodies of water and is visible under a microscope in the form of spiral filaments, hence the name. Judge the good and bad spirulina, mainly look at the following aspects: 1, the content of the ingredients: the main components of spirulina is spirulina polysaccharide, phycocyanin, chlorophyll, carotene and so on. High content of natural quality is good. 2, origin: generally speaking, Guangxi, Yunnan region's geographic conditions are most suitable for the growth of spirulina, other areas of spirulina usually need to artificially create the environment for the growth of spirulina, generally used to dig ponds or pipeline breeding, water, various nutrients and alkalinity of the water to use artificial mixing. There are algal species degradation, growth environment control is not strict and other disadvantages. Natural growth of spirulina does not exist in the above situation, but spirulina growth conditions are very harsh, the temperature and humidity requirements are relatively high, generally only the Beihai, Guangxi and Yunnan Chenghai Lake area to have such conditions. 3, the manufacturer's qualifications: through the health food GMP certification of manufacturers of general product quality have a very good guarantee; if there are other quality certificates and international certificates are more secure. 4, Health food approval number: health food approval number to apply for time-consuming and laborious, usually only the more powerful manufacturers can apply down; and these products are tested by the national authority, does have certain effects. Of course, there is no approval number can not say that there is no such effect, just in accordance with national regulations can not carry out the efficacy of publicity. Comprehensive evaluation: first place: northern spirulina, reason: 1, the same amount of price is the lowest; 2, the highest content of active ingredients, spirulina polysaccharide, carotene, chlorophyll content is the highest, only phycocyanin is slightly lower than the Kangyuan spirulina; 3, with health food approval number; 4, GMP factory production. The only drawback is that the origin is Shandong, not Guangxi with superior natural conditions. Second: green fairy spirulina, reason: 1, guangxi beihai production; 2, have health food approval number; 3, GMP factory production; 4, get international certification; 5, long history, high brand awareness; 6, the price is really third: kangyuan spirulina, reason: 1, guangxi beihai production; 2, get a number of awards; 3, have health food approval number; fourth: green A spirulina: green A is the old brand. Should have been the first, but after careful analysis, found that its cost-effective is not very high, the price is slightly more expensive, the content of the active ingredient is not very high, but the ads do so much, sell more expensive is also normal. If people who are superstitious about the brand can still consider it.