Everything DoseRank tracks on the spirulina shelf — Iron. The category itself is never ranked: 70 products get scored the moment you say what you want them to do.
How to read the scores
This legend covers the scores on this page — for data sources, scoring weights, and limits, read the full methodology →
Answer a few questions about your goals, habits, stack, and budget. Then, DoseRank will find the products that best match your needs based on your answers. It's free and only takes 60 seconds! No account is required.
A saved, shareable breakdown: your matched products, dose math, interaction flags to discuss with a clinician, and a price-tracked stack you can revisit.
Questions
Each product gets a composite score blending clinical strength, evidence, dose fit, trust and value — computed for the goal you picked, across this category's products. The #1 on the DoseRank tab has the highest composite; the other tabs re-rank the same products by Value, Trust, or Popularity. Placement is never paid.
Start with a goal, not a brand
Browsing spirulina supplements without a goal makes no sense — different products do different jobs, and “best” flips depending on which job you're hiring for. These are the 45 health outcomes that matter for this category. Pick yours, and the full evidence-ranked shelf loads for that goal alone.
HemoglobinBlood oxygen-carrying protein concentration.42 rankedStrong
Bleeding tendencyExcess susceptibility to bruising or bleeding.15 rankedStrong
Coagulation statusOverall blood clotting tendency.13 rankedStrong
Macular pigment optical densityRetinal pigment measure sometimes used in lutein/zeaxanthin studies.11 rankedStrong
Vitamin A statusBiochemical sufficiency of retinoids or carotenoid-derived vitamin A.22 rankedStrong
Contrast sensitivityAbility to distinguish shades or low-contrast details.6 rankedStrong
Anemia statusPresence of clinically meaningful low red cell mass or hemoglobin.43 rankedStrong
Eye strainVisual fatigue or discomfort from eye use.9 rankedModerate-strong
Night vision or dark adaptationAbility to see or adapt under low-light conditions.12 rankedStrong
FerritinMarker of iron stores.42 rankedStrong
Vitamin K statusBiochemical sufficiency of vitamin K.13 rankedStrong
Age-related macular degeneration progressionWorsening retinal degeneration affecting central vision.19 rankedStrong
Lean body massNon-fat body mass, often used as a marker of preserved musculature.45 rankedStrong
Skin hydrationMoisture content or hydration of the skin.9 rankedModerate-strong
Cataract progressionWorsening of lens opacity over time.9 rankedModerate-strongNothing is ranked yet — the shelf stays locked until you pick a goal.
No goal, no ranking.
A “best spirulina supplement” list without a goal would be marketing, not evidence. Pick what you want to improve and DoseRank scores all 70 products against that goal's trials.