3. Cod liver oil (2,438 mg per serving)
As the name implies, it’s an oil extracted from the livers of cod fish.
This oil is high in omega-3 fatty acids and loaded with vitamins D and A — a single tablespoon provides 170% and 453% of the Daily Value (DV), respectively.
Therefore, taking just 1 tablespoon of cod liver oil more than satisfies your need for three essential nutrients.
But don’t take more than 1 tablespoon at a time, as too much vitamin A can be harmful.
Omega-3 content: 2,438 mg of EPA and DHA (combined) per tablespoon
4. Herring (2,150 mg per serving)
Herring is a medium-sized oily fish. It is often cold-smoked, pickled, or precooked and sold as a canned snack.
Smoked herring is a popular breakfast food in countries such as England, where it’s called kippers and served with eggs.
A 3.5-oz (100-g) serving of herring contains almost 100% of the DV for selenium and 779% of the DV for vitamin B12.
Omega-3 content: 2,150 mg of EPA and DHA (combined) in 3.5 oz (100 g)