Mercenaria mercenaria
2 associations assessed — none with dependable human evidence behind them yet. Strongest first.
Burrowing filter-feeding bivalves harvested wild and farmed on intertidal flats, eaten raw on the half shell, steamed open, or chopped into chowder. The USDA entry here covers mixed species, raw.
Also known as Quahog, Littleneck, Steamers, Vongole, Manila clam
What each association actually rests on, and the papers behind it. A rating describes the state of the research, not how impressive the food is. How we rate evidence.
Has been studied as a source of well-absorbed iron. Clams are among the densest animal sources of iron and vitamin B12, but almost all the human evidence concerns iron status in general rather than trials that fed people shellfish.
Insufficient evidence. Not enough human research to say anything useful yet.
May support muscle protein synthesis as a lean complete protein. This rests on seafood protein quality generally; bivalves have not been tested for this outcome.
Insufficient evidence. Not enough human research to say anything useful yet.
Answers are written only from the entries on this page — the same nutrients, compounds, claims and citations you can read above. Nothing is added from outside the database, and every answer lists what it was built from.
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| Nutrient | Amount | % DV |
|---|---|---|
| Macronutrients | ||
| Calories | 86 kcal | 4% |
| Protein | 14.7 g | 29% |
| Total fat | 0.96 g | 1% |
| Carbohydrate | 3.57 g | 1% |
| Fibre | 0 g | 0% |
| Total sugars | 0 g | — |
| Water | 79 g | — |
| Fats | ||
| Saturated fat | 0.187 g | 1% |
| Monounsaturated fat | 0.12 g | — |
| Polyunsaturated fat | 0.192 g | — |
| Cholesterol | 30 mg | 10% |
| ALA (omega-3) | 0.015 g | — |
| EPA (omega-3) | 0.043 g | — |
| DHA (omega-3) | 0.064 g | — |
| DPA (omega-3) | 0.0070 g | — |
| Linoleic acid (omega-6) | 0.042 g | — |
| Vitamins | ||
| Vitamin A | 90 µg | 10% |
| Vitamin C | 0 mg | 0% |
| Vitamin D | 0 µg | 0% |
| Vitamin E | 0.68 mg | 5% |
| Vitamin K | 0.2 µg | 0% |
| Thiamin (B1) | 0.015 mg | 1% |
| Riboflavin (B2) | 0.04 mg | 3% |
| Niacin (B3) | 0.35 mg | 2% |
| Pantothenic acid (B5) | 0.148 mg | 3% |
| Vitamin B6 | 0.01 mg | 1% |
| Folate | 5 µg | 1% |
| Vitamin B12 | 11.3 µg | 470% |
| Choline | 65 mg | 12% |
| Minerals | ||
| Calcium | 39 mg | 3% |
| Iron | 1.62 mg | 9% |
| Magnesium | 19 mg | 5% |
| Phosphorus | 198 mg | 16% |
| Potassium | 46 mg | 1% |
| Sodium | 601 mg | 26% |
| Zinc | 0.51 mg | 5% |
| Copper | 0.053 mg | 6% |
| Manganese | 0.085 mg | 4% |
| Selenium | 30.6 µg | 56% |
| Other measured compounds | ||
| Beta-carotene | 0 µg | — |
| Alpha-carotene | 0 µg | — |
| Lycopene | 0 µg | — |
| Lutein + zeaxanthin | 0 µg | — |
| Caffeine | 0 mg | — |
| Ash | 1.82 g | — |
Nutrient values are per 100 g of the USDA reference entry named on this page and vary with variety, growing conditions, storage and preparation.
Source record: Mollusks, clam, mixed species, raw (USDA FoodData Central, FDC ID 174214).
% DV uses the FDA Daily Values for adults and children aged 4 and over. A dash means no Daily Value has been established for that nutrient.
Compounds present in meaningful amounts. Presence is banded rather than quantified, because whole-food levels vary enormously with variety, growing conditions, storage and preparation.
Fatty acid
A family of polyunsaturated fatty acids. The long-chain forms EPA and DHA come mainly from seafood and algae; the plant form ALA converts to them…
Amino sulfonic acid
Concentrated in shellfish and dark poultry meat; involved in bile salt conjugation and cell volume regulation.
Only effects with real support are listed. If a preparation method is missing, it is because nothing dependable is documented — not because it makes no difference.
Thorough cooking is the only step that reliably inactivates Vibrio species and substantially reduces viral load. Shells opening is not by itself a reliable sign that the required temperature has been reached throughout.
Allergies, interactions and intake concerns. Every food gets this section — a reference where everything is uniformly good is not a reference.
Worth knowing
Raw and lightly steamed clams and oysters are the main food vehicle for Vibrio vulnificus, which causes rapidly progressing sepsis with a high fatality rate in people with liver disease, haemochromatosis, diabetes or immunosuppression. Hot sauce, lemon juice and alcohol do not inactivate it; cooking does. For anyone in those groups, raw bivalves are among the few genuinely dangerous foods in an ordinary diet.
Worth knowing
Filter-feeding bivalves concentrate saxitoxins from harmful algal blooms, causing paralytic shellfish poisoning with tingling, weakness and, in severe cases, respiratory paralysis, and domoic acid, causing amnesic shellfish poisoning with lasting memory impairment. Both toxin groups are heat-stable and survive cooking, which is why regulators monitor and close harvest areas rather than advising longer cooking.
Allergy
A regulated allergen group distinct from crustaceans, and a recognised cause of anaphylaxis. Clam appears in stocks, sauces and chowder bases where it may not be obvious.
Worth knowing
Bivalves filter large volumes of water and concentrate enteric viruses from sewage contamination. Norovirus outbreaks from raw and lightly cooked shellfish are common, and depuration reduces bacterial load far more effectively than viral load.