Billed as being a super protein, what is ‘Spirulina’, and is it all it’s cracked up to be?

Spirulina is a cyanobacterium (form of algae), which lives naturally in tropical and subtropical alkaline lakes with high concentrations of carbonate and bicarbonate. As well as being cultivated into dietary supplements for human consumption, it is also used as a feed supplement or fish and poultry.

Fans of spirulina boast that it has many health benefits, mainly due to its protein and micronutrient content.

It’s nutritional content is as follows (per 100g):

  • 290kcal
  • 24g carbohydrate (of which 3g is sugar and 3.6g is dietary fibre)
  • 8g fat
  • 57.5g protein
  • 28mg iron

Dried spirulina is around 60% protein. It’s a ‘complete’ protein, in that is contains all essential amino acids required for health, including leucine. Companies selling dried spirulina recommend using 5 – 15g product each day – added into water, juice or another beverage. Someone taking 5-15g spirulina a day would consume an additional 15 – 45kcal and 3-9g protein. In addition, micronutrients of note would include 1.5 – 4.5mg iron (10 – 30% daily requirements), riboflavin (vit B2, providing 15-45% of daily requirements, and thiamine (vit B1, providing 10-30% of daily requirements). The calcium content (and many other micronutrient content) in this dose is not really significant.

I was sent a sample of 100% organic ‘Super Greens’. This supplement contains 33% spirulina, with the rest being made up barley and wheat grass leaf powder and chlorella. Because there are other things added to some spirulina-containing supplements, the protein content of this particular supplement is 44% (which is still pretty decent!) Iron content is not listed on the nutrition information. There are no proven health benefits of chlorella (or chlorophyll) or barley / wheat grass leaf powder. Any foods / supplements claiming to ‘cleanse’ of ‘detoxify’ should be taken with a pinch of salt – see my blog on detox to read more on this.

Do I need it?

  • Most people eating a healthy balanced diet will get enough protein without the need for spirulina. In fact, UK dietary surveys show that the majority of people eat more protein that they need
  • Dairy foods, e.g. milk and yoghurt also contain all essential amino acids for health, and are considered ‘high quality protein’, so including 2-3 sources of dairy produce a day is the way to go
  • If you include a variety of meat, fish, egg, beans / pulses, and fortified breakfast cereals, it’s likely you’ll meet your daily iron requirements without the need for supplements
  • Spirulina supplement may be a useful way for people to increase their protein and iron intake. Spirulina may be more beneficial to vegans or vegetarians where iron requirements may be harder to achieve due to lack of meat or fish.



The post Spirulina – Super or Spoof? appeared first on Expert Dietitian.


Annemarie Aburrow

Annemarie graduated from the University of Southampton in 2003 with a first class honours in Physiology with Nutrition. She went on to study a Postgraduate Diploma in Dietetics at Cardiff Metropolitan University, leading to registration as a Dietitian. Between 2005 and 2013, Annemarie worked for the NHS in a wide variety of clinical and community roles. More recently, she has specialised in health promotion and prescribing support. She has particular experience in obesity management (both adults and children), diabetes, nutrition for the under 5s and nutritional supplement prescribing. In 2013, Annemarie left the NHS to set up her private practice 'Expert Dietitian'. She now works as a freelance Dietitian, offering private consultations in Hampshire, telephone and Skype appointments, corporate nutrition consultancy and bespoke training. She has a growing portfolio of project work, including working with her local council to provide nutrition training and expertise to Early Years settings, article writing, work with schools and running training/workshops. Annemarie is a member of the British Dietetic Association (BDA) and is registered with the Health and Care Professions Council (HCPC).

Add a comment

Your email address will not be published. Required fields are marked *