At TheHealthBoard, we're committed to delivering accurate, trustworthy information. Our expert-authored content is rigorously fact-checked and sourced from credible authorities. Discover how we uphold the highest standards in providing you with reliable knowledge.

Learn more...

How do I Choose the Best Spirulina Tablets?

A.E. Freeman
A.E. Freeman

Spirulina, or blue green algae, has a number of healthy nutrients, from B vitamins to iron and from vitamin E to zinc. It's also high in protein and antioxidants. You may wish to take spirulina tablets to boost your immune system to ward off disease or to treat your allergies. When choosing tablets, it's important to find a brand that you can trust. Tablets containing spirulina can be contaminated with heavy metals if the algae was grown in a natural setting. The best tablets are therefore those tested for contaminants and produced in a laboratory under controlled conditions.

Look for spirulina tablets that are tested for contaminants. Spirulina can be contaminated with bacteria or microcystins, which can damage your liver. Contaminated spirulina tablets are most likely not safe to consume, as you may end up with an infection in your throat or nausea and diarrhea. If the bottle of spirulina tablets does not clearly state that they were tested and are free of bacteria and other toxins, you may want to find a bottle that is labeled or take the time to call the manufacturer. If you do not get a clear answer, leave the bottle on the shelf.

Pregnant women should not take spirulina tablets.
Pregnant women should not take spirulina tablets.

You may want to buy spirulina tablets that are produced in a laboratory under controlled and cleanly conditions. Spirulina grown in natural bodies of water such as lakes are more likely to contain bacteria or to be contaminated with toxins, especially if the water they were grown in contained metal contaminants. Lab-grown spirulina is also more likely to have a standardized quality. The amount of sunlight and the water temperature can affect the nutrient value of the algae. Those factors can be more easily controlled in a laboratory.

Contaminated spiulina tablets may cause a throat infection if consumed.
Contaminated spiulina tablets may cause a throat infection if consumed.

Some manufacturers may dilute their spirulina tablets with starch, which helps to bind the tablet, while others use only spirulina in the tablet, which leads to a more potent tablet. Some tablets may contain up to 20 percent fillers or binders. Your body may not absorb the nutrients from diluted tablet as effectively as from pure tablets.

If you are considering taking spirulina, you should exercise care before taking the tablets. If you have an auto-immune disorder, spirulina may counteract any immunosuppresent medication you are taking. You should also avoid taking spirulina if you suffer from phenylketonuria, as the tablets contain phenylalanine, which can worsen your conditions. Don't take the tablets if you are pregnant or breastfeeding, as there is not enough information on the safety of the tablets for pregnant women.

Discussion Comments


There have been a number of online sites "debunking" various brands of Spirulina, either for bacterial contaminants or for starch and other fillers. Be careful of the supplement manufacturer.

This Spirulina company in Thailand was started by an American grad from Georgia Tech, and they are using a closed bioreactor system to produce pure Spirulina in fresh paste and powder form. They are really close to obtaining proper FDA importing paperwork to make the products available in the US.


Do not buy spirulina from pacific ocean or from Hawaii. The Fukushima disaster has contaminated a lot of sea life in these areas and there is a measurable amount in California up to 4 REMS. 5 REMS is considered enough for evacuation.

I would be prudent and try to source from somewhere else. I've heard of producers making it organically in commercial inland operations.


Hawaiian pacifica brand is the best, tablet or powder. I've been taking it for years and had no problems just benefits. Everyone has a choice you can read all you like, but it comes down to how you feel when your on any supplement. Start small and slowly increase. If you feel good stick to it. If you don't, stop it. Good luck everyone!


When I was looking for an energy boost, my friend who is really into nutrition, recommended I try some spirulina.

I buy spirulina Pacifica that comes from Hawaii. From what I can tell, this is a good product that is grown in a zone that is free of herbicides and pesticides.

This comes from ponds in Hawaii and from the Pacific Ocean. It is always good to know where your product is made and what kind of tests are run.

Manufacturers of health food supplements aren't required by law to take these extra measures. That is why I would rather spend a little bit more and buy from a company that ensures the quality of their product.


Has anyone noticed any spirulina side effects after taking this supplement?

I wonder if I might have some spirulina that is contaminated or if I just need to give my body a chance to adjust.

After taking some spirulina tablets for a few days I had diarrhea. I tend to have a sensitive stomach, so often need to give myself a chance to adjust to something new.

I purchased this spirulina at a local health food store. I just assumed what I was buying was safe for me. There are many sources that recommend taking spirulina, and I was hoping it would help with the terrible allergies I get in the spring.

At this point I don't know which is worse - the allergies or the side effects. If it doesn't clear up, I will find something else to help with my allergies.


After I came down with a case of mono, I was looking for ways to build my immune system back up and have increased energy.

A friend of mine recommended I try wheatgrass and spirulina. That was the first time I had ever heard of spirulina, and didn't realize that algae could have so many positive benefits.

Until reading this article, I also didn't know how many contaminants could be in this product. I am going to call the manufacturer on my bottle and see what kind of testing they do.

I want to continue taking this, but also want to make sure I am taking a product that is safe for me.


@burcidi - I have spirulina in both tablet and powder form. Unfortunately the powder just sits on the shelf and never gets used.

I thought I could mix this in with my smoothies and I would not notice the taste. Even in a smoothie, I still get a hint of that seaweed taste. Also, just a little bit of powder makes the drink look green.

Depending on what other kinds of fruit and vegetables I have mixed in with it, the color may not look very appealing.

Even though I know what's in it, and how good it is for me, I have a hard time swallowing something that doesn't look good or taste good.

Because there can be many spirulina benefits for my immune system, I continue to take the tablets on a daily basis. I don't know if I will ever get through that bag of powder spirulina or not.


@alisha-- Actually, the powder and tablet are not exactly the same. There are claims out there that the binders used in tablets make it more difficult to digest and absorb the supplements. So it is possible that the powder will be more easily absorbed by the body and the spirulina health benefits will be more.

There is a company however that now makes spirulina tablets without any binders or fillers. I believe they have a whole new technique for making the tablets where they only use pressure to bind them and nothing else.

I'm going to find those spirulina tablets and order them. I don't like the taste of the powder either and I don't want to waste my money on tablets with fillers and binders.


@burcidi-- I haven't tried them in capsule form, so I can't say anything about that. But I have tried both spirulina powder and tablets. I would definitely recommend the tablets over the powder.

The powder has a pretty bad taste and as much as I tried to mix it with juices, the taste of the algae always came through. Tablets are less messy, more efficient and have no flavor! So I like spirulina a lot better in tablet form.

I don't think there is any difference between them benefit wise. The tablets are also made from spirulina powder, it's just binded together, that's all. So if you get organic spirulina tablets, which is the kind I use, it will have the same benefits as organic spirulina powder.

I always buy my spirulina tablets from organic stores. When a supplement is labeled as certified organic and is sold at a well known organic store, I feel confident that it's safe. I never get my supplements from unknown internet suppliers.


I got sick a lot this past winter so I've been looking for a supplementation that can strengthen my immune system. A friend of mine mentioned spirulina and said that it's really beneficial for the body and will definitely have a positive effect on my immune system.

She is not using the tablets though, she takes spirulina in powder form. As far as I know, it's either in powder form, tablet form or capsule form.

What I would like to know is if there is an advantage or disadvantage of taking spirulina in one form or the other. I want to make sure that I'm getting the most benefits of spirulina, so I haven't decided which kind I want to use yet.

Has anyone tried spirulina in different forms? Can you tell me your thoughts on them? Would you recommend tablets over the other two kind?

Post your comments
Forgot password?
    • Pregnant women should not take spirulina tablets.
      By: adam121
      Pregnant women should not take spirulina tablets.
    • Contaminated spiulina tablets may cause a throat infection if consumed.
      By: Aleksandar Todorovic
      Contaminated spiulina tablets may cause a throat infection if consumed.
    • Spirulina contaminated with bacteria or microcystins can damage a person's liver.
      By: pankajstock123
      Spirulina contaminated with bacteria or microcystins can damage a person's liver.