Every 100 kcal of spirulina brings 19.8 g of protein. On that measure it ranks 2nd of the 105 vegetables in this database and 57th of all 796 foods on the site. Measured by weight instead, its 57.5 g per 100 g ranks 1st in its group.
About 79% of the calories in spirulina come from protein, which makes it extremely protein-dense - close to the practical ceiling for a whole food. Foods in this band are the ones that let you raise your protein intake without raising your calorie intake much at all.
Weight for weight, spirulina has 7.4 g of protein for each gram of fat (57.5 g against 7.72 g per 100 g).
Set against artichoke, another vegetable entry in the database, a serving carries about 0.5 g more protein (artichoke has 3.5 g per 1 medium).
It is a complete protein - it supplies all nine essential amino acids in adequate amounts, so it can carry a meal's protein on its own. The serving quoted here is measured by volume at 7 g, and it covers about 8% of the 50 g FDA Daily Value for protein.
Spirulina supplies all nine essential amino acids, which is unusual for a plant source, though a typical spoonful is a small serving.
Serving sizes
Protein in common portions of spirulina
Protein and calories in Spirulina for 100 g, the site serving and USDA household portions.
Portion
Weight
Protein
Calories
100 g
100 g
57.5 g
290 kcal
1 tbsp (serving used here)
7 g
4 g
20 kcal
1 cup
112 g
64.4 g
325 kcal
Portion weights are the household measures listed on the USDA record; protein and calories scale from the per-100 g figures.
Amino acids
Essential amino acids in spirulina
The nine essential amino acids in Spirulina, per 100 g, per serving and per gram of protein.
Amino acid
Per 100 g
Per serving
mg per g protein
leucine
4.95 g
0.35 g
86
lysine
3.02 g
0.21 g
53
valine
3.51 g
0.25 g
61
isoleucine
3.21 g
0.22 g
56
threonine
2.97 g
0.21 g
52
phenylalanine
2.78 g
0.19 g
48
methionine
1.15 g
0.08 g
20
histidine
1.08 g
0.08 g
19
tryptophan
0.929 g
0.07 g
16
Per-100 g values are the amino acid analysis on the USDA record. The serving and per-gram-of-protein columns are arithmetic on those values; they are not a protein quality score.
SampleWhat goal trends look like after a week
109 g
Average per logged day
4 of 7
Days goal met
71%
Complete-protein share
Mon
Tue
Wed
Thu
Fri
Sat
Sun
Sample figures for one made-up week against a 110 g goal, not your data. Red bars met the goal. Your own log fills this in with Premium.
Related
Other vegetables by protein per calorie
Swap for more protein per calorie
Watercress - 20.9 g per 100 kcal, 0.8 g per 1 cup chopped
57.5 g. The 1 tbsp serving used on this page weighs 7 g and so carries 4 g.
How much protein do you get per 100 calories of spirulina?
19.8 g. That figure divides its 57.5 g of protein per 100 g by its 290 kcal per 100 g, so it does not depend on serving size.
Is the protein in spirulina complete?
Yes. The protein in spirulina supplies all nine essential amino acids in adequate amounts, so it can carry a meal's protein on its own.
What share of the protein Daily Value is one serving of spirulina?
About 8%. One 1 tbsp serving has 4 g, and the FDA Daily Value for protein is 50 g.
Figures from USDA FoodData Central record #170495 (Seaweed, spirulina, dried), SR Legacy data. USDA data is in the public domain. Values are the published reference figures for that record, not lab measurements for a specific brand or batch.