Herring: Nutrition, Mercury, Pickled Herring and Safety

Herring is a small, oily, silver fish that swims in large schools in the North Atlantic and North Pacific. It is eaten grilled or fried, cold-smoked as kippers, salted, and above all as pickled herring in vinegar brine or cream sauce. So is herring healthy? In USDA data, cooked Atlantic herring supplies protein, the marine fats EPA and DHA, several times the Daily Value for vitamin B12 and a useful amount of vitamin D, and the FDA and EPA place herring in their lowest-mercury group of fish. The catch is preparation: pickled and kippered herring carry roughly seven to eight times the sodium of plain cooked herring. This guide covers herring nutrition by form, mercury, pickled herring, and the food-safety points that apply to raw, smoked and pickled fish.

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

What is herring?

Atlantic herring and Pacific herring are close relatives in the same family as sardines and shad. They are small, fast-growing fish with soft bones and a rich, oily flesh, which is why herring is so often preserved rather than sold fresh. You will meet it in a few main forms:

• Pickled herring: salted fillets marinated in a vinegar, sugar and spice brine, or in a sour cream or mustard sauce, sold in jars in the refrigerated aisle.
• Kippers: whole herring split open, salted and cold-smoked, often sold canned or refrigerated.
• Salted and matjes herring: young herring that are lightly salted or brined, common in the Netherlands and Scandinavia.
• Fresh or frozen herring: grilled, fried or baked like other small oily fish.

If you already eat small oily fish, our guides to sardines, anchovies and mackerel cover their closest cousins at the fish counter.

Herring nutrition by form

The table uses the USDA FoodData Central SR Legacy database, per 85 grams (about 3 ounces), with percent Daily Values from the FDA. Pacific herring has no vitamin D value in SR Legacy, so that cell says not listed.

A few points stand out in the USDA numbers. Vitamin B12 is the headline: every form of herring in the table supplies more than a full day’s Daily Value, which is why herring appears in our guide to vitamin B12 foods. Cooked Atlantic herring also provides close to a quarter of the vitamin D Daily Value, unusual for any food, and our vitamin D foods guide compares it with other fish. Selenium is high across the board; our selenium guide explains what that mineral does and why more is not better from supplements.

Herring is also one of the richer sources of the long-chain marine fats EPA and DHA in USDA data. The NIH Office of Dietary Supplements lists herring with salmon, mackerel, tuna and sardines as cold-water fatty fish that contain high amounts of these fats. For what EPA and DHA are and how fish compares with capsules, see our omega-3 guide and our krill oil vs fish oil comparison.

Is herring healthy? Mercury and the FDA advice

Mercury is the first question many people ask about fish, and herring scores well. The FDA and EPA advice about eating fish, revised in October 2021 and written for people who might become or are pregnant or breastfeeding and for children ages 1 to 11, places herring in its lowest-mercury group, alongside salmon, sardines, anchovy and Atlantic mackerel. FDA monitoring data from 2005 to 2012 found a mean of 0.078 parts per million of mercury across 27 herring samples. For contrast, the same FDA table lists a mean near 1 part per million for swordfish, which our sibling swordfish guide covers.

How often to eat fish is a personal question that depends on age, pregnancy and the rest of your diet. The FDA chart itself gives the official guidance for its audience, and a clinician or registered dietitian can help you apply it. Herring fits a pescatarian pattern well, and plain cooked herring is low in sodium. The healthfulness question really turns on which form you choose, which is where pickled herring comes in.

Pickled herring: sodium, sugar and labels

Pickling changes the nutrition profile in three ways that USDA data shows clearly. First, sodium: one ounce of pickled herring holds about 11% of the Daily Value for sodium, and 85 grams about a third, per USDA. Second, carbohydrate: plain herring has none, so the carbohydrate in the USDA pickled entry comes from the pickling ingredients, typically sugar; SR Legacy gives no separate sugar figure. Third, some of the protein and B12 per bite is diluted by brine and onions.

• Read the jar: wine-brine, cream-sauce and mustard-sauce versions differ widely in sodium, sugar and fat, so the Nutrition Facts label is more useful than any average.
• Watching sodium: our low sodium foods guide explains the FDA Daily Value of 2,300 milligrams and how to read sodium on labels.
• MAOI medicines: the FDA-approved prescribing information for phenelzine (Nardil), an MAOI antidepressant, lists pickled herring among foods patients must avoid because of the risk of a dangerous rise in blood pressure. If you are prescribed an MAOI, follow your prescriber’s food list.

Kippers, raw herring and food safety

Smoked and raw herring bring their own cautions, all from official sources:

• Kippered and smoked fish in pregnancy: CDC advises pregnant women to avoid refrigerated smoked seafood unless it is in a cooked dish, and names products labeled kippered, smoked, lox or nova-style.
• Parasites: CDC notes that anisakiasis, also known as herring worm disease, comes from eating raw or undercooked fish or squid and can cause stomach pain, nausea, vomiting and allergic reactions. CDC advises cooking seafood to an internal temperature of at least 145 degrees Fahrenheit, or freezing it under specific conditions, such as at minus 4 degrees Fahrenheit or below for 7 days.
• Scombroid poisoning: CDC lists herring with mackerel, sardines and tuna as fish that can form histamine when not kept cold. Histamine is not destroyed by cooking, pickling, salting or smoking, and the fish can look and smell normal, so keep herring refrigerated from store to table.
• Allergy: fish is one of the nine major food allergens under US law, so packaged foods must declare it.

People who follow a low-purine eating pattern on a clinician’s advice can check our purine guide, which covers oily fish. And if you want a milder fish with more of a white-flesh texture, our trout guide is a good next stop.

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: Swordfish: Nutrition, Mercury and Is It Healthy?, Sardines: USDA Nutrition, Benefits, Mercury and Sodium, Omega-3: Benefits, Foods, Side Effects and Heart Research.