I remember in the 1970s hearing about spirulina from my mother and her friends. They were talking about spirulina as being a replacement for regular ‘food’ because it contained so many nutrients. I think my mother tried eating [or drinking] just spirulina for a while, but found it too difficult to replace all of her food with spirulina tablets or powder. I don’t remember if I tried it then or not. That sort of ended that experiment with the ‘supplement of all times’!
Fast forward to 2014, and I’ve been eating or using spirulina in my foods [such as salads, smoothies and the like] for many years now on the assumption that spirulina is a healthy additional substance (based on all those ‘alternative health people’ telling me that spirulina is good for me!). However, I was just going on assumptions based on what I’ve heard and what little I’ve read, and I’ve been wondering if my assumptions are accurate. So, I wanted to dig a little deeper and find out if spirulina is indeed a healthy and nutritious substance for humans to eat, and whether or not it is an important addition to a vegan or raw food diet.
What is spirulina? Is it a healthy, nutritious superfood? Is it important for vegetarians, vegans or raw fooders? Does spirulina help make us more ‘alkaline’? Does it contain important nutrients such as protein, vitamins, minerals, or other elements as have been described and touted by some in the ‘alternative health’ industry?
I did some research, starting with a general internet search, and didn’t find anything scholarly [peer-reviewed]. Then I did another general internet search using a different search engine, and found some interesting articles that I was able to obtain from a library. Here are some highlights of what I discovered from scholarly, peer-reviewed articles (the articles are the numbers in parentheses; see references) on the subject of spirulina:
1. What is spirulina? It is a “microalgae that includes a diverse group of prokaryotic and eukaryotic photosynthetic microorganisms that can grow rapidly due to their simple structure. They are microscopic unicellular organisms capable of converting solar energy to chemical energy using photosynthesis” (4, p. 4123). Nuhu says that calling cyanobacteria algae is a misnomer as they are true prokaryocytes that are very similar to eubacteria (3, p. 1). Cyanobacteria, another form of algae, is one of the oldest known microorganisms, having been dated to 3.5 billion years ago on our planet (4, p. 4123).
2. Some of the many bioactive compounds found in microalgae include: 50-70% protein [also 1, p. 1231; 3], 30% lipids, 8-14% carotene, polyunsaturated fats [PUFAs or essential fatty acids some of which humans can’t synthesize [also 5, p. 480], astaxanthin, acetogenins, bromophenols, terpenes, sterols, alkaloids, minerals, carbohydrates, y-linoleic acid, antioxidants (1, p. 1231; 3, p. 2; 6, p. 96 ), and “fairly high concentrations of vitamins B1, B2, B3, B6, B9, B12, C, E, K, D, and others” (1; 4, p. 4124, 4125, 4127). The minerals in spirulina are Potassium, Calcium, Chromium, Copper, Iron, Magnesium, Manganese, Phosphorous, Selenium, Sodium, Zinc (1, p. 1231). Spirulina also contains enzymes, such as lipase (1, p. 1231). The broad composition of spirulina is this: protein, 50-70%; carbohydrates, 12-15%; lipids, 6-13%; nucleic acids, 4.2-6%; and minerals, 2.2-4.8% (1, p. 1231).
3. Vitamin B12 bioavailability: there has been much discussion in different arenas regarding the actual bioavailability of nutrients found in different foods, such as the tomato and lycopene, where researchers have claimed that the lycopene is absorbed and utilized by the body only when cooked, but the research results about this topic is still being debated. Regarding the bioavailability of B12 in spirulina, according to some authors (1, p. 1232), only 36% of the B12 in spirulina is “active in humans”, which means that although there may be a higher than necessary amount of B12 in spirulina, the human body may not be able to synthesize and utilize all of it. The other vitamins and minerals found in spirulina appear to be more bioavailable, in general, however. For example, iron, B1, B2, and B3 are shown to be absorbed by the human body in appropriate amounts (1, p. 1232).
4. “Calcium, phosphorous, and magnesium are present in quantities [in spirulina] comparable to found in milk” (1, p. 1232).
5. Some cyanobacteria have been found to have toxic properties, but not spirulina (3, p. 2).
6. Anitoxidant properties of Spirulina have been attributed to phycocyanin and allophycocyanin, which are called phycobiliproteins (3, p. 2).
7. Spirulina fusiformis has been found to have free radical scavenging activities (3, p. 2). Peptides are also important components (“bioactive substances”) found in marine organisms, including microalgae.
8. Enzymes, such as superoxide dismutase and lipase, are also found in microalgae (1, p. 1231; 5, p. 483).
9. Docosahexaenoic acid (DHA) is currently being manufactured from microalgae (more on DHA in another article) (4, p. 4125).
10.The Omega-3 fatty acids that have been touted as reducing coronary heart disease, and thus, many practitioners have been recommending taking fish oil supplements or eating more fish instead of other meat, are thought to come from the plankton in the ocean’s food chain (4, p. 4128).
I have a bottle of spirulina that I purchased through Costco. On the label I see: “Nature’s Multi-Vitamin” and “All Natural” and “Pure Hawaiian Spirulina Pacifica.” I’ve actually been to the laboratory in Kailua-Kona, Hawaii [a huge outdoor facility] that produces this spirulina and have seen their production process myself. And, even though it’s grown on the island where I live, it’s still very expensive to purchase even on the island. For the “supplement facts” part of the label, I read [notice the genus and species name]:
Serving size: 1 teaspoon (3 g)
Amount per serving
< 1 g
Hawaiian Spirulina (Arthrospira platensis)
Gamma Linolenic Acid [GLA]
Superoxide dismutase (SOD)
*Percent Daily Values (DV) are based on a 2,000 calorie diet.
**Daily Value not established.
In conclusion, it appears that spirulina would be a valuable addition to a raw fooder, vegan or vegetarian diet [or just about anyone else’s diet], although I don’t think I’d call it a ‘superfood’. There appear to be plenty of nutrients that are valuable for this group of people, especially protein [as one answer to “Where do you get your protein?” question, although there is a low percentage of protein available in one teaspoon] and Vitamin B12 which is a concern for many on a vegetarian, vegan or raw food diet (although vegans and raw foodists may still want to take a supplement for B12 due to the fact that not all of the B12 found in spirulina is absorbed by the human body) . Whether or not it helps with the alkalinity/acidity issue, I am unsure. It wasn’t discussed in any of the literature [peer-reviewed scholarly articles] that I found or could find. It was also a bit confusing when reading about microalgae whether the authors are referring to different species or specifically Spirulina spp. For example, in some articles I read, the authors seemed to be saying that specific nutrients come from a different species of microalgae. However, it appears that, in general, what is sold as “spirulina” would be adequate and probably accounts for most of the nutritional spirulina sold as consumable for humans. Be sure to purchase from a reputable source; I’ve gotten a ‘bad’ batch of spirulina once from NOW. Just one time, though, in all the years I’ve been buying it. Nori and Chlorella may also be valuable additions to a healthy diet, as they also contain bioavailable B12 (2).
I don’t eat spirulina every day, but maybe I should put it in more things, such as smoothies and salads. I do like to put it in my “modified guacamole” and sometimes the ‘souper salad’ that a friend and I created [see recipes]. Thus, I encourage you to consider adding it [and, perhaps, Chlorella and nori; you can mix and match!] to your nutritional plan; spirulina appears to be a healthy and nutritional alga that could be added to many of your recipes. The taste is not unpleasant, but if you put it in a smoothie (certainly in green smoothies!) or a raw soup or something like that, you might not even be able to taste it! Or, perhaps, you might develop recipes that incorporate spirulina to make healthful, green spirulina dishes! Go raw! :)
1. Hoseini, S.M.; Khosravi-Darani, K. & Mozofari, M.R. 2013. Nutritional and medical applications of spirulina microalgae. Mini-Reviews in Medicinal Chemistry, 13, 1231-1237.
2. Kumudha, A; Kumar, S.S.; Thakur, M.S.; Ravishankar, G.A. and Sarada, R. 2010. Purification, identification, and characterization of methylcobalamin from Spirulina platensis. Journal of Agricultural Food Chemistry, 58, 9925-9930.
3. Nuhu, Abdulmumin A. 2013. Spirulina (Arthrospira): An important source of nutritional and medicinal compounds. Journal of Marine Biology, p. 1-8.
4. Priyadarshani, I and Rath, B. 2012. Bioactive compounds from microalgae and cyanobacteria: Utility and applications. International Journal of Pharmaceutical Sciences and Research, 3(11), 4123-4130.
5. Raposo, M.F. dJ.; de Morais, R.M.S.C.; and de Morais, A.M.M.B. 2013. Health applications of biocompounds from marine microalgae. Life Sciences, 93, 479-486.
6. Samuels, R; Mani, U.V.; Iyer, U.M., and Nayak, US 2002. Hypocholesterolemic effect of spirulina in patients with hyperlipidemic nephrotic syndrome. Journal of Medicinal Food, 5(2), p. 91-6.