When you're eating less overall, oily fish — one of the few real food sources of EPA and DHA — is easy to skip. A daily omega-3 supplement fills that gap without adding much volume. The two main options are fish oil (made from anchovies, sardines, or similar small fish) and algae oil (made from the marine algae that fish eat). Both deliver the same omega-3 fatty acids your body uses.
The choice between them comes down to practical factors: tolerance, diet, and budget. Fish oil costs less per gram of EPA and DHA; algae oil skips the fish entirely, which matters if you follow a plant-based diet or find fish burps hard to stomach when appetite is already low. On a GLP-1 journey, the question is simple — which one will you actually take consistently?
Fish oil
Fish oil
Fish oil is the most widely used omega-3 supplement, made by concentrating EPA and DHA from small, oily fish. The triglyceride (rTG) form absorbs well and is the standard by which other forms are judged. It's the lowest-cost way to reach a meaningful daily EPA + DHA amount.
Pros
- +Lowest cost per gram of combined EPA + DHA
- +Extensive purity testing infrastructure — IFOS-certified options easy to find
- +rTG form is well-absorbed with a small amount of fat
Cons
- –Fish burps or aftertaste can be unpleasant on a low-appetite stomach
- –Not suitable for vegans or people avoiding marine animal products
Algae oil
Algae oil
Algae oil comes from the microalgae at the base of the marine food chain — the original source fish get their omega-3 from. It delivers EPA and DHA without any fish, making it fully plant-based. Taste is typically neutral and the form is well-absorbed.
Pros
- +Plant-based — suitable for vegans and people avoiding fish or shellfish
- +No fish aftertaste, which helps on a sensitive or low-appetite stomach
- +Same EPA and DHA the body uses; absorbed comparably to fish oil
Cons
- –Costs more per gram of EPA + DHA than standard fish oil
- –Fewer third-party-tested brands to choose from compared to fish oil
Common questions
Is algae oil as effective as fish oil for omega-3?+
Yes. Fish get their EPA and DHA from algae, so algae oil delivers the same fatty acids at the source. Absorption studies show comparable bioavailability between algae oil and rTG fish oil when taken with a meal containing a little fat. The main practical differences are taste, plant-based suitability, and price — not effectiveness.
How much omega-3 should I take on a GLP-1?+
A common general-wellness target is 1-2 g of combined EPA + DHA per day — not total fish oil or algae oil weight, but the specific EPA + DHA amount listed separately on the label. When you're eating less and oily fish drops off the menu, a daily supplement fills that gap without adding much food volume. A dietitian can refine the amount based on your overall diet.
Why do fish burps happen, and how do I reduce them?+
Fish burps come from oxidized oil or capsules opening in the stomach. Refrigerating the bottle slows oxidation significantly. Taking the capsule with food rather than on an empty stomach also helps — especially relevant on a low-appetite day when your stomach may be partly empty. Enteric-coated capsules dissolve further down the digestive tract and reduce burping for most people.
Can I get enough omega-3 from food instead of a supplement on a GLP-1?+
Two to three servings of oily fish a week (salmon, sardines, mackerel) can cover general omega-3 needs for many people. When appetite drops and meal variety narrows, fish is often the first food to disappear. Track a few honest weeks. If oily fish is showing up consistently, a supplement may be redundant. If not, a small daily capsule covers the gap without adding food volume.
Build your free protocol
Answer 5 quick questions and the Health Food Experts build a clean, personalized supplement + food protocol around your journey.
Build my protocol →Free. No account needed.
Go deeper on each nutrient
General wellness and nutrition information, not medical advice. We help with nutrition, not medication — talk to your clinician or pharmacist about your medication and routine.