32.5g Protein at Only 158 kcal: Cuttlefish Has the Highest
Steamed cuttlefish delivers 32.5g protein per 100g at 158 kcal — a protein-to-calorie ratio of 20.6g per 100 kcal [1]. This is the highest protein density among all commonly eaten seafood: octopus has 29.8g, squid has 17.9g, and shrimp has 20.9g per 100g cooked.
A 3-oz serving (85g) provides 27.6g protein at just 134 kcal [1]. To match this protein intake from chicken breast, you'd need approximately 90g (148 kcal). Cuttlefish delivers the same protein with 10% fewer calories and dramatically more micronutrients.
Research on cuttlefish (Sepia recurvirostra) nutrient composition confirmed crude protein levels of 15-18% in raw tissue, with amino acid profiles showing particularly high concentrations of glutamic acid, aspartic acid, and lysine — essential amino acids important for the body's nitrogen balance [2].
Where a Single Serving Exceeds Full Daily Riboflavin
Steamed cuttlefish provides 1.73mg riboflavin (vitamin B2) per 100g — 133% of the daily value [1]. A 3-oz serving delivers 1.47mg (113% DV) — the only common protein food where a standard serving completely covers the daily riboflavin requirement.
Raw cuttlefish already starts at 0.91mg riboflavin per 100g (70% DV) [1]. Cooking concentrates this to extraordinary levels. For comparison, milk (the food most commonly associated with B2) provides 0.17mg per 100ml (13% DV) — cuttlefish has 10x the riboflavin density of milk.
Riboflavin is essential for energy metabolism, functioning as a precursor to FAD and FMN — coenzymes involved in the electron transport chain. It also plays a role in the metabolism of iron and the activation of other B vitamins. The high riboflavin in cuttlefish complements its high iron content [3].
More Iron Than Beef Liver, from a Seafood You Can Grill in 5 Minutes
Steamed cuttlefish delivers 10.84mg iron per 100g — 60% of the daily value [1]. This surpasses even beef liver (6.5mg/100g braised) and makes cuttlefish the second-highest iron source among common seafood, just behind dried octopus.
A 3-oz serving provides 9.2mg iron — 51% DV [1]. For those tracking iron intake, this single serving comes close to the full daily requirement (18mg for women, 8mg for men). The iron is in the heme form with 15-35% absorption rates.
The raw form already contains 6.0mg iron per 100g (33% DV) [1]. Cooking nearly doubles the concentration as water evaporates. Combined with the high vitamin C content (8.5mg/100g cooked), which enhances iron absorption, cuttlefish provides an internally optimized iron-absorption package [2].
Not a Squid, Not an Octopus
Cuttlefish belong to the order Sepiida — separate from squid (Teuthida) and octopus (Octopoda). Their defining feature is the cuttlebone, an internal calcified structure that serves as a buoyancy device. This internal bone is composed of aragonite (calcium carbonate) and contributes to cuttlefish's uniquely high calcium content [1].
Steamed cuttlefish contains 180mg calcium and 580mg phosphorus per 100g [1]. Compare this to squid (38mg calcium, 252mg phosphorus) and octopus (106mg calcium, 279mg phosphorus). The cuttlebone's mineral matrix enriches the surrounding tissue with calcium.
From a tracking perspective, cuttlefish is nutritionally distinct from squid: 32.5g vs 17.9g protein, 1.4g vs 7.5g fat, and 10.8mg vs 1.2mg iron per 100g cooked [1]. Despite looking similar when cleaned and sliced, substituting one for the other creates significant tracking errors — particularly in iron (9x difference) [3].
Tied with Octopus and Mussels for the Highest Selenium
Steamed cuttlefish delivers 89.6mcg selenium per 100g — 163% of the daily value [1]. This is the exact same concentration found in cooked octopus (89.6mcg) and cooked mussels (89.6mcg) — the three highest-selenium mollusks all converge at this remarkably consistent level.
A 3-oz serving provides 76.2mcg selenium (139% DV) [1]. Even raw cuttlefish starts at 44.8mcg per 100g (82% DV). The doubling with cooking occurs because selenium is bound to the amino acid selenomethionine in the protein matrix and concentrates as water evaporates.
Combined with the 5.4mcg vitamin B12 (225% DV) in the same 100g serving, cuttlefish provides a dense combination of selenium and B12 — two nutrients that work together in selenoprotein synthesis and methionine metabolism [2].
Cuttlefish vs. Related Cephalopods (per 100g Cooked)
| Nutrient | Cuttlefish (steamed) | Octopus (boiled) | Squid (fried) | Shrimp (boiled) | Scallops (steamed) |
|---|---|---|---|---|---|
| Calories (kcal) | 158 | 164 | 175 | 99 | 111 |
| Protein (g) | 32.5 | 29.8 | 17.9 | 20.9 | 20.5 |
| Total Fat (g) | 1.4 | 2.1 | 7.5 | 1.3 | 0.8 |
| Iron (mg) | 10.8 | 9.5 | 1.2 | 0.3 | 0.65 |
| Riboflavin (mg) | 1.73 | 0.08 | 0.42 | 0.02 | 0.02 |
| Selenium (mcg) | 89.6 | 89.6 | 45.0 | 42.1 | 21.7 |
Practical Tips for Cuttlefish
- 1
32.5g protein at 158 kcal per 100g — the highest protein density of any commonly eaten seafood. A 3-oz serving beats chicken breast for protein at fewer calories [1].
- 2
1.73mg riboflavin per 100g (133% DV) — no other common protein food provides a full day of B2 in a single serving. Cuttlefish has 10x the riboflavin of milk [1].
- 3
10.8mg iron per 100g steamed (60% DV) — more iron than beef liver. Combined with 8.5mg vitamin C in the same tissue, creating a natural iron-absorption enhancer [1].
- 4
Cuttlefish is NOT squid — they differ in protein (32.5g vs 17.9g), fat (1.4g vs 7.5g), and iron (10.8mg vs 1.2mg) per 100g cooked. Don't substitute one for the other in tracking [1].
- 5
Sodium jumps to 744mg per 100g cooked (from 372mg raw) — this doubles because water loss concentrates all minerals. Account for this in daily sodium tracking [1].
Frequently Asked Questions — Cuttlefish
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Is cuttlefish the same as squid?
Is cuttlefish high in iron?
Why is cuttlefish high in calcium?
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Important Notice
Nutritional values are based on USDA FoodData Central data for mollusks, cuttlefish, mixed species, raw (FDC 174215) and cooked, moist heat (FDC 172010). Grilled values are estimated from steamed data adjusted for additional moisture loss. Actual values vary by species, origin, size, and cooking method. Cuttlefish is a distinct species from squid (calamari) and octopus — do not interchange values. This tool is for informational and nutrition journaling purposes only — it is not a substitute for guidance from a qualified nutrition professional.
About the Author
Certified fitness professional and nutrition researcher with over 10 years of experience in the fitness and wellness industry. Founder of Food Nutrify, dedicated to making accurate, science-backed nutrition data accessible to everyone through free, easy-to-use calculators.
References & Sources
- [1] USDA FoodData Central (2024). Mollusks, cuttlefish, mixed species, raw (FDC 174215); cooked, moist heat (FDC 172010). U.S. Department of Agriculture, Agricultural Research Service.
- [2] Ramasamy M, Balasubramanian S (2012). Proximate Nutrient and Mineral Composition of Cuttlefish (Sepia recurvirostra). ResearchGate — Journal of Aquatic Food Product Technology.
- [3] Toader-Williams A, et al. (2020). Nutritional and functional properties of cephalopod species. Notulae Biologicae.