Hi Dr. Feigenbaum and Dr. Baraki,
I am new to barbell medicine and I have recently watched a bunch of your guys content. It’s been very interesting, especially as someone who has a background in healthcare, so thank you.
Late in the screening podcast Jordan mentioned how he does not recommend healthy people get screened for Vitamin D except for those with chronic disease. The USPSTF concluded that there is insufficient evidence to provide a recommendation for healthy adults, so their recommendation is “no recommendation” since they are uncertain of any benefits (see https://www.acpjournals.org/doi/10.7326/M14-2450). I think this is an important distinction. By providing the recommendation that one shouldn’t get screened, you are actually providing a recommendation when USPSTF’s true conclusion was “no recommendation” or “we don’t really know”.
Moreover, I think it’s interesting that you mention most of the of medical literature supporting Vitamin D screening is in the context of those with a serious disease like liver failure or kidney failure. You then mention that, because of this, if you do not have a serious disease, one doesn’t need to get screened for Vitamin D. I think this could be an error in thinking due to availability bias in the current nutrition literature. As mentioned in the Nutrition Science series of articles by Alan Flanagan, much of the early research on nutrition was this “single-nutrient focus” model and work on specific deficiencies in certain vitamins and minerals manifesting to symptoms that had short latency periods. As the biomedical research progressed and evolved to hold RCT as the gold-standard, they were incorporated into nutrition science into what we’ve now been recognizing as an “awkward fit” due to the complex, multi-factorial nature of nutrients. My point being that if much of the medical literature has historically focused on reductionist nutrition science that deals with severe deficiencies and diseases with short latent periods that illustrates the “one nutrient – one disease" kind of model, you will find less information in the medical literature on things outside of that, specifically diseases that we deal with nowadays that have a long latent period (i.e. cvd). And perhaps this may be what is happening. Heany, in Nutrients, Endpoints, and the Problem of Proof (2008), noted the following:
The original nutrient deficiency diseases were all of short latency and involved discrete body systems and dysfunctions. Rickets, pellagra, and beriberi are good cases in point. And, while the working science has progressed far beyond these beginnings, these short latency diseases have remained the implicit model for much of our thinking about nutritional deficiency and, to a substantial extent, our determination of nutrient intake requirements.
With that said, the current evidence is insufficient with regards to vitamin D deficiency and long latent disease. However, making the recommendation that one should not get vitamin D screening indicates that we do know what’s best, when in reality, we simply don’t know.