By Nicola Shubrook – Registered nutritionist
What is spirulina and how is it usually consumed?
Spirulina is a blue-green algae that is usually consumed either in powder form or as a supplement.
What is the nutritional profile of spirulina?
Spirulina is known as a nutrient-dense food as it is packed full of vitamins, including vitamins A, C, E and B vitamins, as well as a whole host of minerals such as calcium, magnesium, zinc and selenium.
In particular, vitamin C and selenium are both antioxidants and help protect our cells and tissues from damage.
This algae is also an excellent vegan source of iron, providing 2mg per tablespoon (7g) which is about 23% of the Nutrient Reference Value (NRV) for men over 18 years and women over 50 years, and 13% of the NRV for women aged 19-49 years old.
Spirulina is also high in protein, with just 1 tbsp (7g) providing almost 4g of protein per serving.
How well researched are the benefits and risks of spirulina?
Most of the studies that have been conducted to date have been either on animals or in small human trials, so more research is needed before any health claims relating to spirulina can be confirmed.
There has been some research into the benefits of spirulina and its positive effects on blood glucose levels. In 2017 a paper was published which demonstrated that spirulina decreased blood glucose levels in diabetic mice and the researchers suggested that this may be beneficial in the future to those with type 1 diabetes. This is further supported by another study in the Journal of Medicinal Food that found spirulina supplementation of 2g a day for 2 months on 25 individuals with type 2 diabetes helped control blood sugar levels and improved their lipid profile. However, more research is needed before we can say for sure that spirulina is helpful in managing conditions such as diabetes.
A 2010 study on rabbits found that spirulina had anti-atherogenic effects (reducing the build-up of plaque within arterial walls) even when fed a high cholesterol diet.
There is also some evidence that spirulina may help reduce anaemia, although more research is required. One study on 40 older people with a history of anaemia found that supplementing with spirulina helped improve the haemoglobin levels in red blood cells.
There have also been a few trials into…