Why do some companies have vitamin A and D in their cod liver oil, and Dr. Berg does not?

At Dr. Berg Nutritionals, we can only speak to the ingredients and manufacturing practices of our own products, where we have direct knowledge and oversight. We cannot comment on the methods used by other companies, as we do not have insight into their operations.

However, in your research, you may find cod liver oil products with different features. Some brands use cold-pressing methods to retain naturally occurring vitamins A and D. While effective, this process often makes those products far more expensive and comes with tradeoffs: a higher risk of contaminants (such as heavy metals and environmental pollutants), rancid byproducts from oil breakdown, and a shorter shelf life.

Other companies add back synthetic vitamin A, such as retinyl palmitate or retinyl acetate, along with supplemental vitamin D3 (cholecalciferol) after deodorization.

Dr. Berg’s approach is different. Our deodorized cod liver oil undergoes refining to remove impurities and protect against breakdown. This does reduce natural vitamins A and D, but it creates an exceptionally clean and stable oil. Cold-pressed versions cannot always guarantee.

For this reason, Dr. Berg chose not to add synthetic vitamin A or supplemental vitamin D3. Instead, he focused on delivering a clean, simple, and affordable omega-3 oil. If you want a pure wild-caught omega-3 oil that delivers quality without unnecessary additions, Dr. Berg’s Wild-Caught Omega-3 Cod Liver Oil is a premium option.