Clams: Nutrition Facts, Iron, B12 and Safety

Clams nutrition in one line: clams are a lean, high-protein shellfish with remarkable amounts of vitamin B12 and selenium, a useful amount of iron and copper, and, depending on how they are cooked or canned, a lot of sodium. In the USDA SR Legacy database, 3 ounces of cooked clams supply about 22 grams of protein for 126 calories. So are clams healthy? For most people they are a nutrient-dense seafood, with two big caveats: raw or undercooked clams carry a real infection risk, and shellfish allergy is serious. Below are the USDA numbers, what they say about clams iron, canned clams versus fresh, and the safety facts from CDC and FDA.

Peptide Labs does not sell clams or clam products. This article is general nutrition information, not medical advice.

Clams nutrition at a glance

Clams are bivalve mollusks, filter feeders that live in sand or mud on the sea floor. USDA lists them as mixed species, so the numbers below are averages rather than values for one type of clam. Every row is a 3-ounce (85-gram) serving of edible clam meat, the portion USDA uses.

The cooked entry also lists copper at 64% of the Daily Value, manganese at 37%, riboflavin at 28%, phosphorus at 23%, vitamin C at 21%, zinc at 21% and vitamin A at 16% per 3 ounces. Fat is low, under 2 grams, with about 0.24 grams of the omega-3 fats EPA and DHA. Cooked clams list 57 milligrams of cholesterol per serving in USDA data; our guide to cholesterol in foods explains what current guidance says about dietary cholesterol.

Clams and B12: one of the richest sources

Clams are famous for vitamin B12. The USDA SR Legacy entry for cooked clams lists about 84 micrograms per 3 ounces, which is more than 35 times the Daily Value. The NIH Office of Dietary Supplements, using a different FoodData Central entry, lists 17 micrograms per 3 ounces of cooked clams, or 708% of the Daily Value, and ranks clams second only to beef liver. The gap shows how much shellfish values can vary between samples, but on either number clams are one of the richest B12 foods there is. B12 from food is not a reason to skip a clinician’s advice if you have been told you are low; our guides to B12 in foods and vitamin B12 cover who is at risk and why testing matters.

Clams iron: what the numbers really say

Search for clams iron and you will find very large numbers. The current USDA SR Legacy file is more modest for plain clams: 2.81 milligrams of iron per 100 grams of cooked clams, or about 2.4 milligrams (13% of the Daily Value) per 3 ounces. Drained canned clams are similar. The breaded and fried entry in the same USDA database lists 13.91 milligrams per 100 grams, about five times as much, which shows how far individual entries can differ. When you see a clam iron figure, check which food entry and which database it comes from.

NIH notes that seafood, like meat and poultry, contains both heme and nonheme iron, while plants contain only nonheme iron, and that heme iron is more readily absorbed. Among shellfish, USDA data put cooked Pacific oysters at 7.8 milligrams (43% DV) and cooked blue mussels at 5.7 milligrams (32% DV) per 3 ounces, both above plain cooked clams. Our oysters guide and mussels guide have the full numbers, and our iron foods guide compares animal and plant sources. If you have symptoms of low iron, ask a clinician for a blood test rather than guessing.

Canned clams, clam juice and sodium

Sodium is the surprise in the clam numbers. The USDA cooked entry lists 1,022 milligrams of sodium per 3 ounces, 44% of the Daily Value, and raw clams list 511 milligrams. Drained canned clams list only 95 milligrams per 3 ounces, though brands vary widely, so read the Nutrition Facts label. The canning liquid, often sold as clam juice, lists 516 milligrams of sodium per cup in USDA data with almost no calories. Chowders, sauces and fried clams add more salt and fat. If you are watching salt, our low sodium foods guide explains how to read sodium on labels.

Are clams healthy? Benefits and cautions

On nutrient density, clams score well: high protein, very little fat and large amounts of B12, selenium and copper for few calories. The Dietary Guidelines for Americans list seafood among the protein foods to eat in variety and suggest baked, broiled, roasted or grilled methods instead of deep frying, which matters for fried clams. FDA’s fish advice for people who are pregnant, breastfeeding or feeding children puts clam in its lowest-mercury group. For protein comparisons, see our high protein foods guide; for the mineral, our selenium guide.

• Raw clams and Vibrio: CDC says most people get vibriosis by eating raw or undercooked shellfish, especially oysters, and estimates 52,000 US cases a year come from contaminated food. For Vibrio vulnificus, about 1 in 5 people who get the infection die, sometimes within a day or two. CDC’s advice is simple: do not eat raw or undercooked shellfish; cook it first.
• Who is at higher risk: CDC lists people with liver disease, cancer, diabetes, HIV or thalassemia, people on immune-suppressing therapy or stomach acid-reducing medicine, and people with recent stomach surgery. FDA adds that pregnant women, young children and older adults should avoid raw or undercooked shellfish.
• Cooking: CDC advises boiling clams in the shell until the shells open and then boiling for another 3 to 5 minutes, or steaming for another 4 to 9 minutes. FDA advises throwing away clams with cracked shells or that do not open during cooking, and cooking most seafood to 145 F.
• Allergy: FDA lists crustaceans such as shrimp and crab as major allergens, but mollusks such as clams, oysters, mussels and scallops are not on that list, so labels may not call them out. Mollusk allergy still happens; see an allergist, and get urgent care for swelling or breathing trouble.
• Gout: shellfish are often flagged for purines; our purine foods guide explains that topic.

For a lean fish with a very different nutrient profile, see our sibling guide to halibut. And if seafood is your main protein, our pescatarian diet guide covers how to keep variety.

Frequently Asked Questions

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: Halibut: Nutrition Facts, Fat Content, Mercury and Types, Foods High in Iron: USDA List, Heme vs Non-Heme Iron and Absorption, B12 Foods: Animal, Fortified and Vegan Sources Ranked.