Know2eat

Swordfish

Xiphias gladius

What swordfish has been studied for

2 associations assessed — 1 with at least some human evidence behind it. Strongest first.

  • 1 Limited
  • 1 Insufficient
3 things to know first — allergies, interactions and intake limits

About swordfish

A large, long-lived open-ocean predator sold as thick steaks with dense, meaty flesh that holds together on a grill. Its size and position at the top of the food chain are the defining facts about it nutritionally.

Also known as Broadbill, Pez espada, Espadon

Muscle & Physical PerformanceHeart Health

The evidence in depth

Best supported: Limited

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.

Muscle protein synthesis

Muscle & Physical Performance
Limited evidence

May support muscle protein synthesis as a complete protein, a property shared by all fish. Given the advisory limits on how much swordfish anyone should eat, it is not a sensible food to rely on for this purpose when leaner and lower-mercury species do the same job.

Limited evidence. Early human work, or mostly lab and animal research.

1 source

Deep research mode adds each paper’s own conclusion and stated limitations.

Cardiovascular risk markers

Heart Health
Insufficient evidence

Evidence is limited for swordfish specifically, and the general fish and heart association cannot simply be transferred to it. Analyses that separate high-mercury species find the favourable signal for fish intake weakened or absent where mercury exposure is high.

Insufficient evidence. Not enough human research to say anything useful yet.

No source is attached to this association yet, so it is rated insufficient by default. It is listed because people commonly ask about it — not because there is evidence for it.

Ask about Swordfish

Ask about Swordfish

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.

AI explanations are not switched on for this site, so there is nothing to ask here. Everything above is read straight from the database and does not need them.

Key nutrients

Nutrient content per 100 grams
NutrientAmount% DV
Macronutrients
Calories144 kcal7%
Protein19.7 g39%
Total fat6.65 g9%
Carbohydrate0 g0%
Fibre0 g0%
Total sugars0 g—
Water73.4 g—
Fats
Saturated fat1.61 g8%
Monounsaturated fat3 g—
Polyunsaturated fat1.15 g—
Cholesterol66 mg22%
ALA (omega-3)0.027 g—
EPA (omega-3)0.108 g—
DHA (omega-3)0.648 g—
DPA (omega-3)0.141 g—
Linoleic acid (omega-6)0.075 g—
Vitamins
Vitamin A36 µg4%
Vitamin C0 mg0%
Vitamin D13.9 µg70%
Vitamin E2.02 mg13%
Vitamin K0.1 µg0%
Thiamin (B1)0.075 mg6%
Riboflavin (B2)0.053 mg4%
Niacin (B3)7.76 mg49%
Pantothenic acid (B5)0.35 mg7%
Vitamin B60.543 mg32%
Folate2 µg1%
Vitamin B121.7 µg71%
Choline65 mg12%
Minerals
Calcium5 mg0%
Iron0.38 mg2%
Magnesium29 mg7%
Phosphorus255 mg20%
Potassium418 mg9%
Sodium81 mg4%
Zinc0.66 mg6%
Copper0.039 mg4%
Manganese0.011 mg0%
Selenium57.4 µg104%
Other measured compounds
Beta-carotene0 µg—
Alpha-carotene0 µg—
Lycopene0 µg—
Lutein + zeaxanthin0 µg—
Caffeine0 mg—
Ash1.44 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: Fish, swordfish, raw (USDA FoodData Central, FDC ID 173703).

% 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.

Bioactive compounds

Compounds present in meaningful amounts. Presence is banded rather than quantified, because whole-food levels vary enormously with variety, growing conditions, storage and preparation.

How preparation changes things

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.

  • cookedPreserves methylmercury

    No cooking method removes methylmercury; it is bound to protein in the muscle and stays there through grilling, poaching and canning. Trimming fat does not help either, because unlike PCBs and dioxins, mercury is not concentrated in the fat.

Things to know

Allergies, interactions and intake concerns. Every food gets this section — a reference where everything is uniformly good is not a reference.

  • Avoid

    FDA and EPA advice: not to be eaten in pregnancy or childhood

    Swordfish is on the Choices to Avoid list in the joint FDA and EPA fish advice, alongside shark, king mackerel, marlin, orange roughy, bigeye tuna and Gulf of Mexico tilefish. That advice states plainly that women who are pregnant or breastfeeding, women who might become pregnant, and children should not eat these species at all, because methylmercury crosses the placenta and the developing nervous system is the sensitive target.

  • Too much

    Methylmercury accumulation in adults

    Mercury builds up in the body over months, so it is repeated intake rather than a single meal that matters. Adults who eat swordfish frequently can reach blood mercury levels associated with paraesthesia and tremor, and case reports of symptomatic mercury toxicity from habitual swordfish and tuna eating exist.

  • Allergy

    Fish allergy

    A finfish allergen with the usual cross-reactivity between species.