Are Blue-Green Algae Supplements such as Spirulina and AFA a Good Idea?

November 12, 2014

Are Blue-Green Algae Supplements such as Spirulina and AFA a Good Idea?


Recently I have been doing lots of research into “superfoods” to see which live up to the claims and which do not. I have become increasingly concerned about the consumption of blue-green algae supplements which include Spirulina and Aphanizomenon Flos-Aquae (AFA) and here’s why…


I first read about a possible negative effect of blue-green algae in The Paleo Approach by Sarah Ballantyne where she mentions that both Chlorella (a green algae) and Spirulina (a blue-green algae or cyanobacteria) should be avoided by anyone following the Autoimmune Protocol. This is because they can stimulate the immune system. Several studies confirm this (1) (2) (3).


For anyone with autoimmune disease, you do not want to be stimulating the immune system, so these supplements should definitely be avoided. But what about healthy people? Is it a good or bad thing to stimulate certain parts of the immune system? The companies selling these supplements would have us believe it’s a good thing but I don’t actually know.


Interestingly, the studies that one of the companies selling AFA supplements direct us to such as this one: “Consumption of Aphanizomenon flos-aquae Has Rapid Effects on the Circulation and Function of Immune Cells in Humans – A novel approach to nutritional mobilization of the immune system” cannot be found on PubMed, considered by researchers and healthcare professionals to be the gold standard resource for credible scientific studies.


Further research has led me to contact one of the companies (E3 Live) directly. You can read the email I have sent below in full (on 12/11/14) and I will update this post once I get a response with answers so please watch this space! In the meantime, I would NOT recommend taking these supplements.


“I run a health website and see a lot of people on other sites recommending algal supplements such as Chlorella, Spirulina and AFA.


A friend recommended E3-Live to me and I have been doing some research into your product. I found several studies relating to the immune system and possible benefits of consuming AFA, BUT I also found some studies that are not so positive that I would appreciate some guidance on.


I am extremely concerned about research I have read suggesting that blue-green algae supplements such as yours can contain or produce in the body neurotoxins, hepatotoxins and a compound called beta-N-methlyamino-L-alanine (BMAA).




The most concerning paper I have seen is titled Blue-green algae or cyanobacteria in the intestinal micro-flora may produce neurotoxins such as beta-N-methlyamino-L-alanine (BMAA) which may be related to development of amyotrophic lateral sclerosis, Alzheimer’s disease and Parkinson-Dementia-Complex in humans and Equine motor Neuron Disease in Horses.


When I looked up BMAA, the literature says that cyanobacteria PRODUCE this compound BMAA (it is not something the supplements are contaminated with). So even if your product has been tested for purity, this has nothing to do with the production of BMAA by cyanobacteria once in the body. According to Wikipedia, scientists have found that newborn rats treated with BMAA show a progressive neurodegeneration and impaired learning and memory as adults. In addition BMAA has been reported to be excreted into rodent breast milk, and subsequently transferred to the suckling offspring.


It also states that “Studies on human brain tissue of ALS, Alzheimer’s disease, Parkinson’s disease, Huntington’s disease and neurological controls indicated that BMAA is present in non-genetic progressive neurodegenerative diseases but not in controls or genetic-based Huntington’s disease”.




A paper published in 2011 also concerned me – Cytotoxicity of algae extracts on normal and malignant cells. In this study they used AFA (and Spirulina) and concluded that “High AFA concentrations decreased viability of normal marrow cells…these data suggest that algae extracts may inhibit AML cell lines and leukemia blasts, but they may also have potential inhibitory effects on normal hematopoiesis.” This suggests to me that while AFA may have potential in being an anti-cancer treatment (by stimulating the immune system), perhaps healthy people should not be taking it, and it is probably not a good thing for growing children to be consuming? I appreciate that these are in vitro studies but would still like to know your thoughts on these findings.


Another paper published in 2012 titled Toxin content and cytotoxicity of algal dietary supplements looked at the contamination of algal supplements (Spirulina, AFA and Chlorella) with microcystin (MC) toxins.  This study was interesting as it concluded that all the supplements were cytotoxic even when they were not contaminated with MC’s. They conclude in this study “In light of the findings, the distribution and commercial sale of AFA products, whether pure or mixed formulations, for human consumption appear highly questionable”


Tumour-Promoting effects of Cyanotoxins


A paper published in 2010 titled Inhibition of gap-junctional intercellular communication and activation of mitogen-activated protein kinases by cyanobacterial extracts – indications of novel tumour-promoting cyanotoxins?


This paper starts by saying that “Toxicity and liver tumour promotion of cyanotoxins microcystins (MCs) have been extensively studied”. If your purity results prove that E3 Live is not contaminated with MCs then that bit does not apply to your product. However, this study found tumour-promoting effects independent of the MC content and the “strongest responses were elicited by the extracts of AFA”. They conclude, “Our study provides the first evidence of the existence of unknown cyanobacterial toxic metabolites that affect in vitro biomarkers of tumour promotion.”


Another paper looking at the same thing concluded “Since the observed effects of gap-junctional intercellular communication did not correlate with the content of cyanotoxins MCs and cylindrospermopsin in the tested samples, they were most likely induced by unknown compound(s)” and a third paper looking at the same thing again concluded “It provides further evidence on the presence of unknown tumour promoting metabolites in cyanobacteria”.


These papers suggest that we actually don’t know enough yet about the metabolites of cyanobacteria to truly know they are safe for human consumption. Another paper titled Toxin mixture in cyanobacterial blooms starts by stating “Cyanobacteria …are known to produce a broad spectrum of secondary metabolites. The functions/advantages of most of these secondary metabolites (peptides and alkaloids) are unknown”.


In the light of the above, I would appreciate your thoughts – please could you answer these questions:


1. Do you recommend AFA/E3 Live for children?

2. Do you recommend AFA/E3 Live for pregnant or breastfeeding mothers?

3. Can you prove that AFA/E3-Live does not produce BMAA once it reaches the intestinal micro-flora in humans? If you do not know for sure, do you still feel it is safe to recommend E3 Live for consumption by otherwise healthy individuals when there is a strong link between BMAA and neurodegenerative diseases?

4. Do you have any counter studies to show that AFA is NOT cytotoxic or that it DOES NOT have tumour-promoting effects?


I will await your response to this email. I believe that companies like yourselves have a responsibility to provide consumers of your product with all necessary information about your product, including contraindications, so that they may make an informed decision about whether this product is right for them.”


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