Know2eat

Herring oil

Clupea harengus

What herring oil has been studied for

3 associations assessed — 3 with at least some human evidence behind them. Strongest first.

  • 2 Moderate
  • 1 Limited
4 things to know first — allergies, interactions and intake limits

About herring oil

Oil rendered from the whole bodies of herring, and one of the standard industrial sources of the long-chain omega-3 fatty acids EPA and DHA. It is a body oil rather than a liver oil, which matters: it does not carry the large preformed vitamin A load that fish liver oils do.

Also known as Fish body oil, Marine omega-3 oil, Herring fish oil

Heart HealthInflammation

The evidence in depth

Best supported: Moderate

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.

Blood lipid profile

Heart Health
Moderate evidence

Research consistently shows marine omega-3 oils lowering blood triglycerides, with the effect size scaling with dose and with starting triglyceride concentration. This is one of the most replicated findings in nutrition, supported by many randomised trials and multiple meta-analyses. LDL cholesterol tends to move slightly in the opposite direction, which is part of the same well-characterised picture.

What may be going on: EPA and DHA reduce hepatic very-low-density lipoprotein assembly and secretion and increase fatty acid oxidation in the liver.

Moderate evidence. Several human studies point the same way, with real caveats.

1 source

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

Cardiovascular risk markers

Heart Health
Moderate evidence

Large randomised trials of omega-3 supplements report small reductions in some cardiovascular endpoints, particularly coronary events, with little effect on total mortality or stroke. Results differ substantially by dose and by the specific preparation used, and two of the largest high-dose trials disagreed with each other, so this remains an area of active argument rather than a settled benefit.

Moderate evidence. Several human studies point the same way, with real caveats.

3 sources

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

Inflammatory markers

Inflammation
Limited evidence

Some trials report reductions in C-reactive protein and interleukin-6 with omega-3 supplementation, most clearly in people who already have elevated markers. Effect sizes are small, results across trials are inconsistent, and whether the marker changes translate into anything a person notices is untested.

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

2 sources

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

Ask about Herring oil

Ask about Herring oil

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
Calories902 kcal45%
Protein0 g0%
Total fat100 g128%
Carbohydrate0 g0%
Fibre0 g0%
Water0 g—
Fats
Saturated fat21.3 g106%
Monounsaturated fat56.6 g—
Polyunsaturated fat15.6 g—
Cholesterol766 mg255%
EPA (omega-3)6.27 g—
DHA (omega-3)4.21 g—
DPA (omega-3)0.619 g—
Linoleic acid (omega-6)1.15 g—
Vitamins
Vitamin A0 µg0%
Vitamin C0 mg0%
Thiamin (B1)0 mg0%
Riboflavin (B2)0 mg0%
Niacin (B3)0 mg0%
Pantothenic acid (B5)0 mg0%
Vitamin B60 mg0%
Folate0 µg0%
Vitamin B120 µg0%
Minerals
Calcium0 mg0%
Iron0 mg0%
Magnesium0 mg0%
Phosphorus0 mg0%
Potassium0 mg0%
Sodium0 mg0%
Zinc0 mg0%
Copper0 mg0%
Manganese0 mg0%
Selenium0 µg0%
Other measured compounds
Ash0 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 oil, herring (USDA FoodData Central, FDC ID 172340).

% 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.

  • rawPreserves EPA and DHA

    Marine oils should be kept cold, dark and sealed, and never used for cooking. Their many double bonds make them the fastest of all edible oils to oxidise, and oxidised fish oil both smells rancid and delivers less intact omega-3.

Things to know

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

  • Interaction

    Bleeding risk with anticoagulants and antiplatelets

    Long-chain omega-3 fatty acids reduce platelet aggregation and modestly prolong bleeding time. At supplemental doses, and alongside warfarin, direct oral anticoagulants, aspirin or clopidogrel, this is a recognised interaction that should be discussed with a prescriber before starting, and before any surgery.

  • Worth knowing

    Fish liver oils are a different product

    Cod liver oil and other fish liver oils concentrate preformed vitamin A as retinol, and taking them alongside a multivitamin, a retinol supplement or high-dose vitamin A can push intake into the range associated with hypervitaminosis A — liver damage and, in pregnancy, teratogenic risk. Herring body oil does not carry that load, but the two are sold side by side and are easily mistaken for one another. Pregnancy guidance specifically advises against fish liver oil supplements.

  • Worth knowing

    Oxidation and environmental contaminants

    Marine oils are the most oxidation-prone fats in a kitchen, and independent testing has repeatedly found retail fish oil products already oxidised at purchase. Separately, fish body oils can concentrate dioxins and PCBs unless molecularly distilled, which is why regulators set limits and reputable products publish contaminant testing.

  • Worth knowing

    Fish allergy

    Highly refined fish oils contain very little parvalbumin, the main fish allergen, and most fish-allergic people tolerate them. That is not a universal finding, and unrefined or crude fish oils carry more protein.