Subtotal $0.00
Shop Now
Eel is a long, snake-like fish known in the US mainly as unagi, the grilled, glazed eel served over rice or on rolls at Japanese restaurants. It is rich and fatty, and the USDA SR Legacy entry for cooked eel lists 201 calories per 3 oz, with more than a full day’s Daily Value of both vitamin A and vitamin B12. One safety point sets eel apart from most fish: raw eel blood contains a protein toxin, which is why eel is always cooked. This guide covers eel nutrition, whether eel is healthy, unagi vs anago, the blood toxin, FDA mercury and allergen facts, and how eel compares with other fish.
Peptide Labs does not sell eel or eel products. This article is general nutrition information, not medical advice.
Key Takeaways
- Unagi is freshwater eel and anago is saltwater conger eel; both are served cooked.
- USDA SR Legacy lists 201 calories, 20.1 g of protein and 12.7 g of fat in 3 oz of cooked eel.
- The same serving supplies 107% of the Daily Value for vitamin A and 102% for vitamin B12 in USDA data.
- Japan's health ministry reports that eel serum contains a protein toxin that heat destroys, so ordinary cooking removes the hazard.
- FDA and EPA fish advice does not list eel by name, so a mercury group cannot be given.
- Fish is one of the nine major food allergens under US law, and eel is a bony fish.
What is eel?
Eels are fish, not snakes. The freshwater eels sold as unagi belong to the genus Anguilla, which includes the Japanese eel and the American eel. Their life cycle is unusual: the US Fish and Wildlife Service explains that mature American eels spawn in the Sargasso Sea, and the larvae drift on ocean currents for about a year to the coasts of North America and the Caribbean. There they turn into transparent glass eels, then elvers, then yellow eels, and finally silver eels that swim back out to sea to spawn.
Pre-grilled unagi kabayaki, brushed with a sweet soy glaze, is a common freezer item in Asian groceries, and it is the eel in the rolls covered in our sushi guide.
Unagi vs anago
These two Japanese menu names describe different fish. Unagi is freshwater eel (Anguilla species). It is richer and fattier, and it is usually grilled kabayaki style with a thick, sweet soy-based glaze. Anago is conger eel, a saltwater species. It is leaner and softer, and it is more often simmered in a light broth before being finished with a thinner sauce.
- Both are cooked: Japan’s health ministry lists both unagi and anago among the eels whose blood serum is toxic, so neither is served raw.
- Glaze matters: the sweet kabayaki sauce adds sugar and salt; see our soy sauce guide for its sodium.
Eel nutrition (USDA SR Legacy)
SR Legacy has only mixed-species eel entries; there is no separate entry for unagi, anago or conger eel. The values below come from Fish, eel, mixed species, cooked, dry heat (FDC 174194), using the USDA 3 oz (85 g) portion. They are for plain cooked eel, so they do not include any glaze. %DV uses FDA Daily Values. The cooked entry reports no vitamin D or vitamin E value, so those rows say Not reported.
| Nutrient (USDA SR Legacy) | Per 3 oz cooked (85 g) | Per 100 g cooked |
|---|---|---|
| Calories | 201 | 236 |
| Protein | 20.1 g (40%) | 23.7 g (47%) |
| Fat | 12.7 g (16%) | 15.0 g (19%) |
| Saturated fat | 2.6 g (13%) | 3.0 g (15%) |
| Cholesterol | 137 mg (46%) | 161 mg (54%) |
| Sodium | 55 mg (2%) | 65 mg (3%) |
| Vitamin A (RAE) | 966 mcg (107%) | 1,137 mcg (126%) |
| Vitamin B12 | 2.5 mcg (102%) | 2.9 mcg (120%) |
| Niacin | 3.8 mg (24%) | 4.5 mg (28%) |
| Phosphorus | 235 mg (19%) | 277 mg (22%) |
| Zinc | 1.8 mg (16%) | 2.1 mg (19%) |
| Selenium | 7.1 mcg (13%) | 8.3 mcg (15%) |
| EPA + DHA (omega-3) | 0.16 g | 0.19 g |
| Vitamin D | Not reported | Not reported |
| Carbohydrate | 0 g | 0 g |
Two nutrients stand out in the USDA entry. Vitamin A reaches 107% of the Daily Value in 3 oz, and all of it is listed as retinol, the preformed kind found in animal foods. Vitamin B12 is just over 100% of the Daily Value. Our foods high in vitamin A and B12 foods lists show how eel ranks.
Eel is also fattier than salmon or cod: 12.7 grams of fat per 3 oz in USDA data, with cholesterol at 46% of the Daily Value. The raw entry (FDC 174193) lists 23.3 micrograms of vitamin D per 100 grams, 117% of the Daily Value, but USDA did not report vitamin D for cooked eel, so we cannot say how much remains on the plate. A whole cooked fillet, which USDA weighs at 159 g, carries about 375 calories.
How eel compares with other fish
The table compares 3 oz of each fish cooked by dry heat, using USDA SR Legacy entries: Fish, eel, mixed species (FDC 174194), Fish, salmon, Atlantic, farmed (FDC 175168) and Fish, cod, Atlantic (FDC 171956). %DV uses FDA Daily Values.
| Per 3 oz cooked (USDA SR Legacy) | Eel | Farmed Atlantic salmon | Atlantic cod |
|---|---|---|---|
| Calories | 201 | 175 | 89 |
| Protein | 20.1 g (40%) | 18.8 g (38%) | 19.4 g (39%) |
| Fat | 12.7 g (16%) | 10.5 g (13%) | 0.7 g (1%) |
| Saturated fat | 2.6 g (13%) | 2.0 g (10%) | 0.1 g (1%) |
| Cholesterol | 137 mg (46%) | 54 mg (18%) | 47 mg (16%) |
| Vitamin A (RAE) | 966 mcg (107%) | 59 mcg (7%) | 12 mcg (1%) |
| Vitamin B12 | 2.5 mcg (102%) | 2.4 mcg (99%) | 0.9 mcg (37%) |
| EPA + DHA (omega-3) | 0.16 g | 1.83 g | 0.13 g |
In USDA data, eel and salmon are both rich fish, but their fats differ. Farmed salmon has more than ten times the EPA and DHA of eel, while eel has far more vitamin A and more than twice the cholesterol. Cod is the lean option, with about 89 calories per 3 oz in USDA data. Our salmon, cod and omega-3 guides go deeper.
Is eel healthy?
Eel can fit into a varied diet that includes fish, with a few trade-offs worth knowing. Based on USDA SR Legacy data, it is a good source of protein, vitamin B12 and vitamin A, and a fair source of phosphorus and zinc. It is also higher in fat, saturated fat and cholesterol than lean white fish, and lower in EPA and DHA than salmon. Restaurant unagi adds a sweet glaze, which brings sugar and sodium that the USDA table does not include. See our foods high in cholesterol guide for context on that row.
Vitamin A deserves a note for pregnancy. The vitamin A in eel is preformed, and the NIH Office of Dietary Supplements (ODS) explains that the upper limits for preformed vitamin A apply to food as well as supplements, and that total intakes above the upper limit can cause birth defects. If you are pregnant or may become pregnant, ask your clinician how foods rich in preformed vitamin A, such as eel and liver, fit your diet.
Why raw eel blood is a hazard
Eel blood is not safe raw. Japan’s Ministry of Health, Labour and Welfare (MHLW) lists eels of the group Anguilliformes, including unagi, anago, pike conger and moray, as fish whose blood serum is toxic. According to the ministry’s risk profile, drinking a large amount of fresh eel blood can cause diarrhea, vomiting, rash, irregular heartbeat, weakness, abnormal sensations, paralysis and breathing difficulty, and the ministry notes that deaths can occur. A 2008 study in Protein Journal purified the toxin from Japanese eel serum and found it was a large protein that was lethal to mice by injection.
The good news is that heat destroys it. The MHLW profile reports that the serum toxin loses its toxicity after 5 minutes at 60 degrees Celsius (140 degrees Fahrenheit), so ordinary cooking poses no food-hygiene problem, and Japan has no official record of food poisoning from it. The ministry adds that the bigger risk is in the kitchen: serum that splashes into the eyes or mouth causes intense burning, and serum in a cut can cause redness, pus and swelling, cases it says are well known among eel cooks.
- Never eat eel raw: unagi and anago are always cooked, including on sushi.
- Cook fresh eel through: FoodSafety.gov lists 145 degrees Fahrenheit for fin fish, or until the flesh is opaque and flakes with a fork, which is above the heat level in the MHLW profile.
- Protect yourself when cleaning eel: wear gloves, keep blood away from your eyes, mouth and any cuts, and wash surfaces and knives afterward.
- Pre-grilled unagi is already cooked: reheat it gently according to the package.
Eel mercury facts and food labels
The FDA and EPA Advice about Eating Fish, revised in October 2021, sorts many species into three groups for people who are pregnant or breastfeeding and for parents feeding children. Eel is not listed by name in that advice, so we do not assign it a mercury group or guess at one. If you are pregnant, breastfeeding or feeding young children, ask your clinician about eel, or choose species the FDA lists in its lowest-mercury group, such as salmon and cod.
Fish is one of the nine major food allergens under US law, and FDA guidance counts all bony fish in that group. Eel is a bony fish, so under FDA guidance it is a major food allergen like any other fish. Packaged foods must name the species of fish on the label.
Eel and conservation
In 2015 the US Fish and Wildlife Service reviewed the American eel and found that listing it as endangered or threatened was not warranted at that time, concluding that harvest and trade for food, bait and aquaculture were not threats to the species as a whole. That finding covers only the American eel, so ask your fish seller which species and origin a product comes from.
For another fish with a split personality on menus, see our monkfish guide, and our Japanese diet guide covers how fish fits into traditional Japanese meals.
Frequently Asked Questions
Can you eat eel raw?
No. Japan’s health ministry reports that eel blood serum contains a protein toxin. Heat destroys it, so eel is always eaten cooked.
What is the difference between unagi and anago?
Unagi is freshwater eel, rich and usually grilled with a sweet glaze. Anago is saltwater conger eel, leaner and often simmered.
Is eel healthy?
USDA data show it is high in protein, vitamin A and vitamin B12, but also higher in fat and cholesterol than lean fish and lower in omega-3 than salmon.
Is eel high in mercury?
FDA and EPA fish advice does not list eel by name, so a mercury group cannot be stated. Ask your clinician if you are pregnant.
Is eel a major food allergen?
Yes. Eel is a bony fish, and fish is one of the nine major food allergens under US law.
Questions about a label? Contact us or read our Buyer’s Guide. Food comes first; follow the label and ask a healthcare provider before starting a supplement, especially if you take medicines, are pregnant or have a food allergy. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
Last reviewed October 2026.
Related guides: Monkfish: Nutrition, Taste, Mercury and How to Cook It, Sushi: Nutrition, Raw Fish Safety, Mercury and Pregnancy, Omega-3: Benefits, Foods, Side Effects and Heart Research.