Spirulina

What is spirulina?

Spirulina is a freshwater algae (or seaweed) that grows naturally in tropical and sub-tropical lakes. Historically used as a food by native South American people, it fell into disuse for many centuries until it was recognised as a non-animal protein source in the 1970s. It's dried and made into cakes for use in soups and stews around the shores of Lake Chad, West Africa.

Because it's a supplement rather than a mainstream food, spirulina has not been as widely or deeply researched as other major foods. It offers the full spectrum of amino acids (proteins) but is not considered to be as complete in other nutrition as milk, eggs or meat. It could be of great use where protein is rare, but not as useful in the Western world, where availability of plant-based protein is not an issue.

Vegetarians regarding spirulina as a major protein source will miss out on nutrients unless they're also including eggs and milk in their diet, or still relying on the correct balance of grain and pulses they eat. It could be more useful to vegans, but speak to a GP about your overall diet first – you might need to supplement, for example, vitamin B12.