A complete safety, timing, and dosage guide for combining Cod Liver Oil with Vitamin B1 (Thiamine) — including how the two supplements interact, the best time of day to take each, and which populations should be careful.
Yes, you can take vitamin B1 (thiamine) and cod liver oil together; no significant interaction.
Vitamin B1 (Thiamine) and Cod Liver Oil together are safe. Thiamine is a water-soluble B vitamin, while cod liver oil provides fat-soluble vitamins A and D plus omega-3s. Their absorption pathways are different, so they do not interfere with each other.
Thiamine is absorbed in the proximal small intestine via specialized carrier-mediated thiamine transporters, a process that is independent of dietary fat. Cod liver oil is a lipid that must be emulsified by bile salts and hydrolyzed by pancreatic lipases before it forms chylomicrons and enters the lymphatic circulation. These two pathways do not share receptors, enzymes, or transport proteins, so there is no competition or inhibition. Thiamine's bioavailability is not affected by fat, and cod liver oil's fat content does not change how thiamine is taken up. Both supplements can be taken together without altering each other's metabolism or requiring dose adjustment.
Take cod liver oil with breakfast or lunch, since a meal containing fat will help it absorb well. You can take thiamine at the same time, with water, and it does not matter whether your meal includes fat. If you miss a dose of thiamine, take it with your next meal as soon as you remember, but skip it if it is almost time for your next dose. For cod liver oil, follow the label serving and never exceed it; if you are prone to nausea, divide the dose into two smaller servings with meals. There is no need to separate them by hours, so a simple morning routine works perfectly.
Thiamine is most commonly taken as thiamine hydrochloride, while benfotiamine is a fat-soluble derivative that may achieve higher tissue concentrations; both forms are neutral alongside cod liver oil. Cod liver oil is available as a liquid or in softgels, with the liquid often requiring refrigeration after opening to prevent oxidation. The specific form of either supplement does not change their lack of interaction, though choosing a molecularly distilled cod liver oil can reduce the risk of contaminants.
Thiamine is routinely included in B-complex and energy support formulas alongside vitamin B6, vitamin B12, and magnesium. Cod liver oil is typically sold as a standalone liquid or softgel, occasionally added to vitamin A and D blends, but it is rarely paired directly with thiamine in commercial products.
Yes, you can take them at the same time. I usually recommend taking them together with a meal to make it easier on your stomach. There is no known interaction that would make separate timing necessary.
Yes, it is safe to take both daily at the recommended amounts. I advise following the dose on the cod liver oil label, since excess vitamin A and D can cause problems over time, but thiamine has no daily ceiling that matters at normal supplement doses.
No specific waiting period is needed. You can take them together; if you experience nausea, you might separate them by a few minutes or take them with different meals.
No, they do not compete for absorption. Vitamin B1 uses thiamine transporters in the small intestine, while cod liver oil is digested as fat and absorbed into the lymph system. They take completely separate routes into your body.
Almost anyone can take them together, but if you are pregnant, take blood thinners, or have liver disease, check with your doctor first. The concern is mostly the vitamin A in cod liver oil, not the thiamine.
I suggest taking cod liver oil with a meal that contains fat because that helps it absorb well. You can take thiamine on an empty stomach or with food, so taking both with breakfast is a simple approach.
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.