Omega XL is a dietary supplement built around a 300 mg proprietary blend of green-lipped mussel oil, olive oil, omega fatty acids, and vitamin E. Each small softgel capsule contains this blend plus a shell made from gelatin, glycerin, and purified water. That’s the full ingredient list, but understanding what each component actually does (and what’s notably missing from the label) takes a closer look.
The Proprietary Blend
The centerpiece of Omega XL is an oil extract from the New Zealand green-lipped mussel, listed on the label as PCSO-524. This is a patented extract of Perna canaliculus, a specific mussel species harvested in New Zealand’s Marlborough Sounds. The extract is standardized to contain a mix of omega-3 fatty acids, but it also includes some less common fatty acid types not found in standard fish oil. Proponents of green-lipped mussel oil point to these unique lipids as the reason it may support joint comfort differently than a typical fish oil capsule.
The entire proprietary blend weighs 300 mg per softgel. That blend includes the mussel oil extract, extra virgin olive oil (used as a carrier to stabilize the formula), omega fatty acids, and d-alpha-tocopherol, which is a natural form of vitamin E that acts as an antioxidant to keep the oils from going rancid. Because these are all grouped under one 300 mg label, there’s no way to know exactly how many milligrams of each individual ingredient you’re getting.
How It Compares to Standard Fish Oil
Most conventional fish oil supplements list their EPA and DHA content right on the label, often delivering 500 to 1,000 mg of these two omega-3s per capsule. Omega XL does not break out its EPA and DHA amounts. The entire blend is only 300 mg total, meaning the actual omega-3 content per capsule is significantly lower than what you’d find in a standard fish oil softgel. The recommended serving is two capsules daily, bringing you to 600 mg of the total blend, still well below the omega-3 dose in most fish oil products.
This is the single biggest point of confusion for shoppers comparing labels. Omega XL’s marketing focuses on the idea that the green-lipped mussel extract provides a broader range of fatty acid types (around 30, by the company’s count) rather than a high concentration of just EPA and DHA. Whether that breadth compensates for the lower overall dose is a matter of ongoing debate, and the proprietary label format makes independent comparison difficult.
The Capsule Shell
The softgel itself is made from gelatin, glycerin, and purified water. Gelatin is an animal-derived protein, which means Omega XL is not suitable for vegans or strict vegetarians. The capsules are notably smaller than typical fish oil softgels, which is a selling point the company emphasizes for people who have trouble swallowing large pills.
Allergen Considerations
Because the primary ingredient comes from a mussel, shellfish allergies are a legitimate concern. Green-lipped mussel is a mollusk, and people with confirmed shellfish allergies often wonder whether the oil extraction process removes the proteins responsible for allergic reactions. Oil-based supplements generally go through extensive purification that should eliminate protein allergens, according to the American Academy of Allergy, Asthma & Immunology, but this cannot be guaranteed. If you have a known shellfish allergy, the safest approach is to discuss this specific product with an allergist before trying it.
What’s Not on the Label
Several things are worth noting by their absence. Omega XL does not list individual milligram amounts for EPA, DHA, or any other specific fatty acid. It contains no added flavoring, so some users report a mild fishy aftertaste. There are no added fillers, artificial colors, or preservatives beyond the vitamin E that serves as a natural antioxidant. The product also carries no third-party testing seal (such as USP or NSF) on its standard label, which would independently verify purity and potency.
The “proprietary blend” designation is legal under FDA supplement labeling rules, but it limits transparency. You know the total weight is 300 mg per capsule, and you know which ingredients are present, but the ratio of mussel oil to olive oil to other components remains the manufacturer’s trade secret. For consumers who want to compare cost per milligram of actual omega-3s, this makes Omega XL harder to evaluate against competitors that fully disclose their fatty acid profiles.