Plain dried spirulina is not a caffeine source in USDA FoodData Central: the database lists caffeine at zero and marks the value as an assumed zero because it is not naturally occurring or is insignificant in that food. A drink mix can still contain caffeine if it includes matcha, green tea, coffee, yerba mate or another caffeinated ingredient.
Check whether the product is pure spirulina or a blend
A single-ingredient spirulina powder and a flavoured “greens” blend are different products. Read the complete ingredient list, not only the front label. Look for tea powders, coffee, guarana, yerba mate or added caffeine. If caffeine matters to your routine, check the serving size and the product’s nutrition or supplement information too.
USDA FoodData Central’s entry is for dried spirulina, not a laboratory test of every brand. The database also notes that the zero is assumed rather than a quantified analytical value. So it supports a simple distinction: plain spirulina itself is not expected to contribute caffeine, while mixed products must be checked individually.
What about spirulina in coffee or tea?
Adding spirulina to a caffeinated drink does not remove the caffeine already in that drink. The caffeine comes from the coffee or tea, not from the spirulina. If you want to experiment with a hot beverage, be prepared for a change in colour and flavour, and start with a small amount. Our guide to spirulina in coffee and other hot drinks covers practical mixing and appearance checks.
A product may also combine spirulina with matcha or green tea, which can contribute caffeine. Do not infer caffeine content from a green colour, the word “superfood” or a serving image. The ingredient list is the useful place to start.
How to read the label
- Check whether spirulina is the only ingredient or part of a blend.
- Scan for tea, coffee, guarana, yerba mate and any declared caffeine.
- Confirm the serving size; one scoop and one prepared drink may not be the same amount.
- If the package makes a caffeine claim, look for a quantified amount and testing or formulation basis.
What if you are avoiding caffeine?
Choose a clearly labelled single-ingredient product and confirm the current label before use. If a healthcare professional has advised you to limit caffeine, include all drinks and blends in that conversation. This article explains the ingredient question; it is not individualized medical advice.
AimGrow lists a spirulina powder product. Check the current ingredient and product details on the page before purchasing.
Frequently asked questions
Does pure spirulina powder have caffeine?
USDA FoodData Central lists zero caffeine for dried spirulina and describes that figure as an assumed zero.
Can a spirulina drink mix contain caffeine?
Yes, if it includes tea, coffee, yerba mate, guarana or another caffeine source. Check the full label.
Does adding spirulina to coffee make the drink caffeine-free?
No. The coffee still contains its own caffeine.
Source: USDA FoodData Central: Seaweed, spirulina, dried. The record is for the plain food item, not a branded blend.