Pickled herring is a genuinely nutritious food, packed with omega-3 fatty acids, vitamin B12, and high-quality protein. It does come with trade-offs, though. The pickling process adds significant sodium and often sugar, so how you eat it and how much matters. Here’s what the nutrition actually looks like.
Omega-3 Levels Are Exceptionally High
Herring is one of the richest sources of omega-3 fats you can eat. A 100-gram portion of Atlantic herring contains roughly 700 mg of EPA and 900 mg of DHA, the two omega-3 fatty acids your body uses most readily. That’s about 1.6 grams of combined EPA and DHA, which is well above what most people get in an entire day. The American Heart Association recommends two servings of fatty fish per week (each about 3 ounces cooked), and herring checks that box easily.
Those omega-3s have real, measurable effects on the body. In a clinical trial, overweight adults who ate 150 grams of oven-baked herring five days a week for four weeks saw their HDL (“good”) cholesterol rise significantly compared to a control group eating pork and chicken. Their inflammatory markers also trended downward. Omega-3 supplementation studies have also shown benefits for brain function, including a 26% improvement in executive function tasks and better episodic memory in people who started with lower baseline scores.
Vitamin B12 and Other Micronutrients
Herring is remarkably rich in vitamin B12. A 75-gram serving of kippered Atlantic herring provides about 14 micrograms of B12, which is nearly six times the daily recommended intake for adults. B12 is essential for nerve function and red blood cell production, and it’s a nutrient many people, especially older adults and those on plant-based diets, run low on. Herring also supplies vitamin D, selenium, and phosphorus, though the vitamin D content is modest at around 1.6 micrograms per 75-gram serving.
The Sodium Problem
This is where pickled herring gets complicated. A single ounce of pickled Atlantic herring contains about 247 mg of sodium. Eat a few ounces at a time and you’re looking at a significant chunk of the 2,300 mg daily limit most guidelines recommend. That sodium comes from the brine used in pickling, and it’s essentially unavoidable in commercially prepared versions.
If you’re watching your blood pressure or managing a heart condition, the sodium content is worth taking seriously. Eating pickled herring as an occasional appetizer or snack, rather than a main course, keeps the sodium in check while still giving you the nutritional benefits.
Sugar Is Often Hidden in the Brine
Many pickled herring recipes and commercial brands include sugar in the brine or sauce. A one-ounce serving contains roughly 2 grams of sugar, which can add up quickly depending on how much you eat and whether the herring is packed in a sweet cream sauce or wine-based marinade. Nutrition varies quite a bit between brands and styles, so checking the label is worthwhile if sugar intake matters to you.
Pickled vs. Fermented: No Probiotic Benefit
If you’ve heard that pickled herring is good for gut health because of probiotics, the reality is more nuanced. Most commercially sold pickled herring is preserved in vinegar, not traditionally fermented. Vinegar-based pickling acidifies the fish but doesn’t produce live beneficial bacteria. Truly fermented herring, the kind that requires refrigeration and lists no vinegar in the ingredients, could contain probiotics. But the jars you find on most supermarket shelves are vinegar-pickled and shelf-stable, meaning no live cultures survive.
Mercury Levels Are Low
Herring is a small, short-lived fish, which means it accumulates far less mercury than larger predatory species. FDA monitoring data shows herring has a mean mercury concentration of 0.078 parts per million. For comparison, canned light tuna averages 0.126 ppm, canned albacore tuna hits 0.350 ppm, and shark reaches 0.979 ppm. Herring’s mercury levels are low enough that it’s a safe choice for frequent consumption, including for pregnant women and children who need to be more cautious about mercury exposure.
How to Get the Benefits With Fewer Downsides
Pickled herring gives you the same omega-3s, B12, and protein as fresh or smoked herring, just with added sodium and sugar along for the ride. If you enjoy pickled herring, eating it in small portions a few times a week is a reasonable approach. A couple of pieces on crackers or rye bread delivers meaningful omega-3s without overloading on sodium.
If sodium is a concern, fresh, baked, or grilled herring delivers the same core nutrition without the brine. Canned herring (sometimes labeled as kippers) is another option with lower sodium than the pickled version, though you should still check labels. The fish itself is the nutritional star. The pickling is just one way to enjoy it, not the healthiest way to prepare it.