Spirulina: The Blue-Green Algae That's Been Around Since Before the Dinosaurs
Spirulina is one of the oldest life forms on earth. It's a blue-green algae that's been growing in alkaline lakes for over 3.5 billion years — long before plants, long before animals, long before anything we'd recognise as life. The Aztecs harvested it from Lake Texcoco. NASA has studied it as a food source for long-duration space missions. And it's been used as a daily supplement by health-conscious people for decades.
There's a reason it keeps coming up. The nutritional profile is extraordinary.
What's actually in it
Spirulina is roughly 60–70% protein by dry weight — higher than almost any other food source, including meat. And it's a complete protein, containing all nine essential amino acids in good proportions.
Beyond protein, it contains significant amounts of B vitamins (including B12, though the bioavailability is debated), iron, magnesium, potassium, copper and manganese. It's also rich in gamma-linolenic acid (GLA), a beneficial omega-6 fatty acid, and phycocyanin — the blue pigment that gives spirulina its distinctive colour and has potent antioxidant and anti-inflammatory properties.
For a single ingredient, it covers an unusual amount of nutritional ground.
What people actually use it for
Protein and nutrition — spirulina is popular with vegans and vegetarians as a complete protein source, but it's useful for anyone who wants to increase their protein intake without adding more meat or dairy. A tablespoon adds around 4g of complete protein.
Energy — the iron content makes it particularly useful for people who run low — common in women, vegetarians and people who train hard. Iron deficiency is one of the most common causes of fatigue, and spirulina is one of the more bioavailable plant-based sources.
Detoxification — spirulina has been studied for its ability to bind to heavy metals and help remove them from the body. It's been used in clinical settings in countries with high heavy metal exposure, and there's reasonable evidence for its chelating properties.
Inflammation and antioxidants — phycocyanin, the compound that makes spirulina blue-green, is a powerful antioxidant and anti-inflammatory. It inhibits the production of inflammatory signalling molecules and protects cells from oxidative damage.
Cholesterol and cardiovascular health — multiple studies have shown spirulina can reduce LDL cholesterol and triglycerides while increasing HDL. The effect is modest but consistent.
Gut health — spirulina supports the growth of beneficial gut bacteria and has been shown to inhibit the growth of harmful bacteria like Candida.
How to use it
Spirulina has a strong, distinctive flavour — earthy, slightly oceanic, very green. It's not subtle. The best approach is to blend it into something that can handle it: a smoothie with banana and berries, a green juice, or mixed into a cacao drink where the chocolate flavour dominates.
Start with half a teaspoon and build up to a full teaspoon or tablespoon over time. Some people find large amounts cause mild digestive discomfort initially.
Don't add it to hot drinks — heat degrades some of the more delicate nutrients. Cold or room temperature is best.
A note on sourcing
Spirulina quality and purity matters. It can absorb heavy metals and contaminants from the water it's grown in, so sourcing from clean, controlled environments is essential. Ours is tested for purity and sourced from reputable producers. We wouldn't stock it otherwise.
Worth it?
If you want one of the most nutritionally complete things you can add to your diet — complete protein, iron, antioxidants, anti-inflammatory compounds — spirulina delivers. It's not the most glamorous supplement. But gram for gram, it's hard to beat.
