In this special interlude, I lay down the framework of the five core principles that make a good marker of nutritional status. This is to lay down the framework for a series of podcasts in the future about managing nutritional status for specific vitamins and minerals.

Since these core principles will be referred back to as a general reference in so many other episodes, this one has a special place outside of the sequence and you can reach it at any time with the easy-to-remember URL chrismasterjohnphd.com/interlude.

This episode is brought to you by Kettle and Fire Bone Broth. Use the link kettleandfire.com/chris to get $10 off your first order.

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In this episode, you will find all of the following and more: 37:23 Cliff Notes 09:25 Purpose of this podcast and its place in the upcoming series on managing nutritional status; 11:54 What are the five core principles? 12:05 Principle #1: We understand its biochemistry and physiology; 15:04 Principle #2: It has been validated against changes in nutritional status; 17:17 Principle #3: Sensitivity; 17:52 Principle #4 Specificity; 19:45 Principle #5: It must be interpreted in the overall context of other markers and the clinical and health history, current signs and symptoms, and diet and lifestyle analysis; 23:20 Example of principle #1: Spectracell vs dp-ucMGP as tests of vitamin K2 status; 27:20 Example of principle #2: 25(OH)D vs. calcitriol; 29:20 Example of principle #3: transferrin saturation vs. ferritin 31:08 Example of principle #4: specificity of 25(OH)D and contexts where its specificity fails; 32:50 Example of principle #5: distinguishing between calcium and vitamin D deficiencies as causes of 25(OH)D by testing PTH, calcitriol, and analyzing the diet and lifestyle; 37:50 Shotgun approaches to nutritional testing; 40:30 Whether to act on leads from shotgun approaches should depend on the risks and other costs of the actions.

Access the show notes, transcript, and comments here:

https://chrismasterjohnphd.substack.com/p/what-makes-a-good-marker-of-nutritional

Chris Masterjohn, PhD, is the Founder and Scientific Director of the mitochondria test Mitome.