By Vineet Sikri, MS, RPh, founder of Kurryculum
Short answer: both supply the omega-3s EPA and DHA. Fish oil usually gives you more per capsule for less money. Krill oil delivers its omega-3s in a different form, in a smaller softgel, with naturally occurring astaxanthin. Neither is "better" for everyone. Here's how to choose.
The key difference: the form of omega-3
According to the NIH Office of Dietary Supplements, fish oil carries its omega-3s mostly as triglycerides, while krill oil carries them mostly as phospholipids. Phospholipids are the same type of fat that makes up your cell membranes.
Does that mean krill is absorbed better? Some studies suggest phospholipids have somewhat higher bioavailability. Others find no meaningful difference. The honest answer is that the research hasn't settled it.
Krill oil vs. fish oil at a glance
| Krill oil | Fish oil | |
|---|---|---|
| Omega-3 form | Mostly phospholipids | Mostly triglycerides |
| EPA + DHA per capsule | Lower (Kurryculum: typically 100 mg per 500 mg softgel) | Higher (a typical 1,000 mg capsule has about 300 mg) |
| Absorption | Some studies show somewhat higher absorption | Other studies find no meaningful difference |
| Extras | Naturally occurring astaxanthin | Usually none |
| Capsule size | Usually smaller | Usually larger |
| Cost per mg of EPA + DHA | Usually higher | Usually lower |
| Allergy concern | Shellfish | Fish |
When fish oil makes more sense
- You want the most EPA and DHA for your money.
- Your doctor recommended a specific EPA + DHA amount that would take many krill softgels to reach.
- You have a shellfish allergy. Krill is a crustacean.
When krill oil makes more sense
- You prefer a smaller softgel that's easier to swallow.
- You're interested in the phospholipid form of omega-3s.
- You like that krill oil naturally contains astaxanthin, the carotenoid that gives krill its red color.
- You have a fish allergy but not a shellfish allergy. Check with your doctor first, since some people react to both.
A pharmacist's safety checklist for any omega-3
- Blood thinners. The NIH notes fish oil might prolong clotting time in people taking warfarin. If you take any blood thinner, tell whoever manages your dose before starting krill or fish oil.
- Seafood allergies. Krill oil contains shellfish. Fish oil contains fish. Read the allergen statement.
- Stomach side effects. The most common complaints are an unpleasant taste, bad breath, heartburn and nausea. Taking your softgel with a meal usually helps.
- Vegetarian diets. Most krill and fish oil softgels use gelatin from animals. Check the "other ingredients" line.
- Surgery. Tell your surgeon about any omega-3 supplement you take.
Frequently asked questions
Is krill oil better than fish oil?
Not universally. Krill oil has a different form of omega-3 and a smaller softgel. Fish oil usually delivers more EPA and DHA per dollar. The right choice depends on your priorities and health history.
Does krill oil cause fishy burps?
Any omega-3 can cause an aftertaste in some people. A smaller softgel taken with a meal may help, but results vary from person to person.
Can I take krill oil with collagen or a joint supplement?
For most people, yes. See our guides to collagen and glucosamine, chondroitin and MSM, and ask your own pharmacist to look over everything you take.
Try Kurryculum Krill Oil
Each softgel provides 500 mg krill oil, typically delivering 100 mg phospholipids and 100 mg EPA & DHA, with naturally occurring astaxanthin. 60 softgels. Contains crustacean shellfish (krill). Softgel is made with bovine gelatin. See the full Supplement Facts →
Prefer Amazon? Buy Kurryculum Krill Oil on Amazon →
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. This article is for education and does not replace personal advice from your healthcare provider.