A complete safety, timing, and dosage guide for combining Cod Liver Oil with Copper — including how the two supplements interact, the best time of day to take each, and which populations should be careful.
Yes, you can take copper and cod liver oil together safely. There is no significant interaction between the two, and combining them at reasonable supplement doses is well tolerated.
Taking copper and cod liver oil together is safe, with no meaningful metabolic conflict. Copper and cod liver oil together do not compete for absorption or alter each other's effectiveness when used at typical supplement doses.
Copper is absorbed primarily in the stomach and proximal duodenum, largely through the copper transporter Ctr1, while cod liver oil is a mixture of fat-soluble vitamins (A and D) and long-chain omega-3 fatty acids that are incorporated into chylomicrons after emulsification by bile salts. These two do not share a common transporter, receptor, or absorption pathway, so they do not compete. The vitamin A in cod liver oil does not directly alter copper absorption or ceruloplasmin activity, and omega-3 fatty acids do not chelate copper in the gut. The only indirect concern is that very high doses of vitamin A over time can affect the liver, but that is unrelated to copper metabolism. There is also no evidence that copper influences the absorption of vitamin A or D from cod liver oil.
If you are taking copper supplements and cod liver oil, the simplest approach is to take them together with a meal that contains some fat — for example, breakfast or lunch. This covers both copper's need for a fed state to reduce nausea and cod liver oil's need for dietary fat for optimal absorption. No specific time separation is required. If you also take a high-dose zinc supplement (over 25 mg), take the zinc at least two hours apart from copper to prevent competition. If you miss a dose, just take it with your next meal; do not double up. If you are using a copper glycinate or gluconate product, that is preferable to cupric oxide.
Copper is available as cupric oxide, cupric sulfate, copper glycinate, and copper gluconate; cupric oxide is poorly absorbed, while glycinate and gluconate are generally better tolerated. Cod liver oil is sold as liquid or softgels, and the natural retinol (vitamin A) and vitamin D content varies between manufacturers and can be measured in international units. For copper status, opt for a well-absorbed form like copper glycinate if you have had borderline levels, and choose a cod liver oil product with clear vitamin A and D labeling to avoid excess fat-soluble vitamin intake.
Yes, you can take copper and cod liver oil at the same time. They don't interfere with each other's absorption, so a single meal is fine for both. I usually recommend taking them together with food to avoid stomach upset.
It is safe for most healthy adults to combine copper and cod liver oil every day, as long as you're not exceeding the recommended limits. I recommend staying at or below 900 mcg of copper and not taking more than 3,000 mcg RAE of vitamin A from cod liver oil plus other sources.
You do not need to wait at all; you can take copper and cod liver oil together. Because they use different absorption pathways, there's no timing conflict to manage.
No, they don't compete. Copper is absorbed via the Ctr1 transporter in the upper small intestine, while cod liver oil's fats and vitamins are absorbed into chylomicrons through a completely different process. I haven't seen any science showing these two compete.
People with Wilson's disease, copper overload, or liver disease should avoid copper supplements. Pregnant women should avoid high-dose cod liver oil because of vitamin A. If you're on blood thinners, it's important to talk with your doctor before taking cod liver oil daily.
I recommend taking copper with food to prevent nausea, and cod liver oil with a meal containing fat for optimal absorption. Taking them together at a meal, preferably lunch or dinner, works well.
Reviewed by Caroline M. on April 11, 2026 for accuracy against the sources listed above. This page is educational and is not a substitute for professional medical advice.
The matrix has 86 supplements and 7310 pairwise interactions. Click any cell to see the full breakdown.