Fatty acids

Fatty acids are the building blocks of the fats in your food. Two of them your body cannot make at all: alpha-linolenic acid (ALA), an omega-3 from seeds and nuts, and linoleic acid, an omega-6 from vegetable oils. The long-chain omega-3s EPA and DHA can be built from ALA, but only in very small amounts. That is why oily fish, fish oil and algae get most of the attention, and why the largest part of this collection sits around them.

The number on the front of the bottle is not the dose

A bottle that says 1000 mg is usually telling you the amount of fish oil, not the amount of omega-3. Turn it over and add up the EPA and DHA per daily serving. A standard 1000 mg fish oil capsule often supplies around 180 mg EPA and 120 mg DHA. EPA and DHA contribute to the normal function of the heart at 250 mg a day, so one product reaches that in a single capsule while another needs three. The Omega-3 pages group the higher-strength options.

Forms differ more than the price tag suggests

When fish oil is concentrated, the omega-3 is usually turned into an ethyl ester, a form your body has to convert back before it can use it. Re-esterified triglyceride oils skip that step and absorb better, but they cost more to make. Taken with a fatty meal, an ethyl ester closes much of that gap, so it stays a sensible budget choice if you always take it with food.

• Fish oil: most EPA and DHA per capsule, usually from small fish such as anchovies and sardines.
• Algae oil: the original source of DHA, plant-based, often DHA-forward with less EPA.
• Krill oil: omega-3 attached to phospholipids, but fewer milligrams per capsule.
• Cod liver oil: omega-3 plus vitamins A and D, so keep an eye on your vitamin A total.
• Seed oils: flaxseed for ALA, evening primrose and borage for GLA.

Omega-6 is a smaller part of the picture, because most UK diets already supply plenty of linoleic acid through cooking oils and processed food. People still choose the omega-6 oils for GLA from evening primrose or borage, which behaves differently in the body from ordinary linoleic acid.

How we choose the oils in this range

We look at three things: the form, the dose and whether a combination makes sense. We prefer triglyceride and re-esterified triglyceride fish oils and algae oils, because they absorb well without needing a fatty meal alongside. We ask for EPA and DHA per serving to be printed clearly, not hidden behind a total oil figure. Unspecified cheap concentrates without freshness data do not make it in. We buy directly from the brands, our compliance team checks every product before it goes live, and independent labs spot-check batches. You can read how we select our brands.

Who this suits, and what to expect

This collection fits you if you rarely eat oily fish, follow a plant-based diet, or want a steady daily intake without cooking fish twice a week. If you already eat two portions of fish a week, one of them oily, you are meeting UK dietary advice and a supplement adds less. Levels of EPA and DHA in your blood shift slowly, so give any product two to three months of daily use before you judge it. If you want a set amount rather than a general oil, the concentrated EPA and DHA products make that easier to plan.