Vitamin D content of meat, as a backup for supplements.

For the intake of many vitamins and minerals, we depend on the content of supplements that we take. However, we can not verify if the actual composition of a supplement corresponds to what is written on its label. We can imagine a catastrophic scenario where you would take a supplement for years just to discover one day that the manufacturer made a mistake and the supplement does not contain some of the vitally important minerals or vitamins.

A backup strategy would be to ensure that your food also contains some of the minerals and vitamins that you take as supplements. But is this always possible?

In the case of vitamin D, there are some anecdotes about how consumption of liver or eggs allowed people to increase their blood levels of 25-hydroxycholecalciferol [25(OH)-D-3] (calcidiol, 25(OH)D3). 25(OH)D3 is the major circulating metabolite of vitamin D, and its concentration in blood is used as a measure of vitamin D status.

We decided that it is useful to check the available data on what the content of vitamin D in meats really is. Fortunately, there are published studies that investigated this subject.

Below, there is a table with a compilation of published data on the vitamin D content in different meats. Theoretically, by consuming liver and kidney regularly (daily?), a human can get some meaningful amounts of vitamin D. The amount obtained in this way may not be enough to reach the optimal levels of 25/OH)D3 in the blood, but this can do as a backup. If there is a problem with your vitamin D supplement, you still have a chance to avoid excessively low blood levels of 25/OH)D3.

From Schmid and Walther, 2013:

The RDA of vitamin D for females and males between 9 and 70 y of
age in the United States is set at 15 mg/d (600 IU/d) and also, the Endocrine Society suggests this amount for adults aged 19–50 years, but indicates that to increase the blood level of 25(OH)-D-3 consistently above 30 mg/L, at least 37.5–50.0 mg/d (1500–2000 IU/d) of vitamin D may be required.