Spirulina Powder

Spirulina is sold on nutrient density but studied for other things, so these are the questions our naturopaths ask in store before recommending it.

A good fit if

• You want a concentrated whole food rather than a single nutrient
• You'll buy from a supplier that tests each batch for contamination
• You're interested in the blood lipid research and will give it time
• You'll use it in a smoothie and don't mind the taste

Check with us first if

• You have an autoimmune condition. Spirulina is widely described as stimulating the immune system, and we haven't found research that settles what that means for you.
• You have phenylketonuria (PKU). It's a concentrated protein source, and we haven't found reliable information on its phenylalanine content.
• You take any prescription medicine. Beyond testing with blood thinners, we haven't found interaction data.
• You're buying for a child. We haven't found safety data in children.
• You're not sure whether you want spirulina or chlorella. They're different algae with different rules.

• Powder. Best known for: The cheapest way to take a meaningful amount. Absorption: Whole dried algae, nothing removed. Typical use: Strong taste; most people blend it rather than stir it.
• Tablets. Best known for: Getting past the flavour. Absorption: Same material, compressed. Typical use: You'll need several to match a powder serve.
• C-phycocyanin extract. Best known for: The isolated blue pigment, the most studied constituent. Absorption: An extract rather than the whole alga. Typical use: Studied at around 1 g a day of phycocyanin in the bleeding and liver work.
• Arthrospira platensis or maxima on the label. Best known for: The Schedule 1 names that permit active use. Absorption: Not a form difference, a regulatory one. Typical use: "Spirulina" alone is excipient-only in Schedule 1.
• Chlorella instead. Best known for: A different green algae entirely. Absorption: Carries iodine as a mandatory component. Typical use: Internal use is capped below 300 micrograms of iodine a day.

Reference values. None. Spirulina is a food rather than a single nutrient, so there's no NHMRC reference value for it.

Typical supplemental range. Australian labels usually provide 3 to 10 g a day. A research review gives about 3 to 10 g a day as a safe amount for adults, though that's a review's opinion rather than a legal limit. The bleeding and liver safety testing used 2.3 g a day of a water-based extract, providing roughly 1 g of phycocyanin.

Upper level. There's no NHMRC upper limit, and Australia's permitted ingredients list (Schedule 1) sets no dose limit for Arthrospira platensis (item 702) or Arthrospira maxima (item 701). The 3 to 10 g a day figure from research is the closest thing to a ceiling, but it isn't a legal limit.

Worth knowing. For most people, where it was grown matters more than the dose, because open-pond growing is where the contamination question comes in. What you need depends on your age, diet and health, so talk to one of our naturopaths.

Food first, where the diet allows it.

• Spirulina powder: the food itself; commonly 3 to 10 g a day
• Green smoothie blends: often a small fraction of the serve; check the panel

This list is the part of the page we will not shorten. If any of it applies to you, talk to one of our naturopaths or your doctor before starting.

• Pregnancy and breastfeeding. No Schedule 1 pregnancy warning attaches to items 701, 702 or 4710, and no human pregnancy or lactation data was located.
• Contamination. Spirulina may carry microcystins and other toxins depending on cultivation; the literature reports this as contested rather than settled.
• Autoimmune conditions. Spirulina is widely described as immune-stimulating, and no cached source addresses what that means clinically.
• Phenylketonuria. A concentrated protein source, and no cached source addresses phenylalanine content.
• Children. No age restriction on any spirulina item, and no paediatric safety data was located.
• Medicine interactions. Not captured beyond direct anticoagulation testing, which found no change in platelet activation at 2.3 g/day of aqueous extract.
• Don't confuse it with chlorella (items 1343, 1345), which carries iodine as a mandatory component and is capped below 300 micrograms of iodine a day for internal use.
• If you take prescription medicines, check with your doctor, pharmacist or our naturopaths before starting.