Spirulina has long been used as food and is generally well tolerated, but there are situations in which it is worth discussing it with a doctor or dietitian before you start taking it:
- Pregnancy and breastfeeding — during these periods any supplements are best agreed with a specialist, even if they are marketed as natural.
- Chronic conditions — especially autoimmune conditions, blood clotting disorders or kidney disease: spirulina contains a significant amount of protein and certain minerals, which may matter with certain diagnoses.
- Taking medication — if you take any medicines on a regular basis, ask your doctor about possible interactions.
- Sensitivity to algae and seafood — if you have had allergic reactions to such products, be careful, and if you are intolerant to any of the ingredients, do not use the supplement.
People to whom none of the above applies usually only need to follow the instructions on the packaging. Spirulina is a food supplement; it is not intended to treat or prevent any disease.