In most situations, it is safe to combine Cod Liver Oil and Adcal (Calcium + Vitamin D).

Cod liver oil is a popular supplement that contains numerous beneficial ingredients including:

  • Fish oil (EPA & DHA)
  • Vitamin D
  • VItamin A

The exact content and amount of these constituents will vary depending on the brand used, but products are generally fairly close to one another. Below, is the label for Nordic Naturals Cod Liver Oil:

Cod Liver Oil Vitamin D

There is a mild concern that the vitamin D contained within cod liver oil could potentially increase calcium concentrations in the body, possibly resulting in too high calcium levels (i.e. hypercalcemia). In addition, as you can see from the nutritional label above, cod liver oil contains vitamin A. Large doses of vitamin A can lead to bone loss and could potentially negate the the effects of calcium. The amount of vitamin A contained in cod liver oil products should not be a concern in this case however and should really only be considered if you take additional vitamin A supplements.

Lastly, the amount of Vitamin D contained in cod liver oil isn't overly significant and generally should not result in overdosing on the vitamin if you take it as an additional supplement.

There is no concern with combining thiamine and cod liver oil.