Read the ingredient amounts
The amount of oil is not necessarily the same as the amount of EPA and DHA. The NIH Office of Dietary Supplements describes several omega-3 sources and formulations. Compare the labelled amounts per recommended serving, not just the large number on the front.
Check personal suitability
Show the label to a pharmacist or other qualified professional if you take medicines or have a medical condition. This article does not claim that a store product prevents heart disease or replaces prescribed care.
Common sources on labels
Fish oil, krill oil and algae-based oil are common omega-3 sources, each with different EPA and DHA ratios; algae oil also contains no fish.
Why omega-3 alone is not a complete answer
EPA and DHA are the components most often discussed in relation to omega-3 intake, so comparing products on total fish oil weight alone can be misleading.
What this article does not claim
General dietary guidance discusses omega-3 as part of a balanced diet. That is different from a specific product claiming to prevent or treat a heart condition, which is not stated here.
Fish, krill or algae: practical differences
Krill oil is often marketed on bioavailability grounds, algae oil suits people avoiding fish products, and standard fish oil remains the most common and typically most affordable option. Each has a different EPA and DHA profile.
Aftertaste and digestion
A fishy aftertaste or mild digestive upset is a commonly reported, non-serious experience with fish oil capsules. Taking the capsule with food is a frequently suggested practical step.
Checking freshness
A strong, unpleasant smell or taste beyond a mild fishy note can indicate a product has oxidised. Checking the use-by date is a simple, practical step.
Considering the whole diet, not just one product
General dietary guidance discusses oily fish as a food source of omega-3s alongside, rather than instead of, supplement options, and someone who already eats oily fish regularly may have different supplementation needs from someone who does not. This is a reminder that a supplement is generally framed as filling a specific gap, rather than something everyone needs regardless of their existing diet, and a conversation with a health professional or dietitian can help clarify where an individual’s diet actually sits.
Storage after opening
Keeping fish oil capsules in a cool place, and refrigerating after opening in some cases, is sometimes recommended to slow oxidation, though this depends on the specific product’s own storage directions rather than a universal rule for every brand.
A closing thought on making a choice
With fish oil, krill oil and algae oil all available, and each varying in EPA and DHA content, price, and any dietary considerations such as avoiding fish products, the most useful next step for many people is comparing two or three specific products by their actual EPA and DHA amounts per serving rather than by category name alone. Where any doubt remains, particularly for anyone taking blood-thinning medication or managing an existing heart or circulatory condition, checking with a doctor or pharmacist before starting a new omega-3 supplement is a sensible precaution.
Further reading
Editorial draft — pending client review. General information; not an individual treatment plan.