It seems that there was a recent test of over-the-counter, OTC, vitamin D that was presented at a meeting for the Consortium of Multiple Sclerosis Centers and America’s Committee on Treatment and Research in Multiple Sclerosis. Neurologists typically have their patients with MS take at least 4000 IU of D3 per day. The samples were collected both from drug stores and online. Here is the article. From MedPage Today. The samples had an average value of vitamin D that was 33% of what the labels stated.
As I mentioned on a prior post, there was a problem that was recognized by Dr. William Davis with his cardiologist patients not getting enough vitamin D when using a brand that was purchased at Walgreens. Link to that post here.
As I have discussed many times, the only way that you know if you are getting enough vitamin D is to have your serum tested. Once you have established a brand that keeps your serum level ‘like a sunny country’, stick to that brand. If you decide to change brands, then you need to test. I use a product that is made by Bio Tech Pharmacal. – Pandemic Survivor