Why do my urinary B6 markers say I'm deficient if I'm supplementing and my plasma levels are high-normal? | Masterjohn Q&A Files #300

Short answer: Low or low-normal alkaline phosphatase may raise the plasma B6 level over the cellular level. Tryptophan metabolites in urine reflect the B6 requirement for the kynurenine pathway, and this requirement increases with more estrogen, more inflammation, or a higher protein intake. This is a clip from a live Q&A session open to CMJ Masterpass members. In addition to this episode, you can access five other free samples using this link: https://chrismasterjohnphd.substack.com/p/questions-on-vitamin-d-fatty-liver In that batch of free episodes you will also find the answers to these questions: What's the difference between 25(OH)D and 1,25(OH)2D when it comes to the VDR? Reversing Fatty Liver: How Long Does It Take? What if my A1C says I'm diabetic but my CGM says I'm fine? Will reishi, turmeric, or curcumin tank my testosterone? The 3 Phases of Fasting: And How to Get Kicked Out of Each One If you want to become a Masterpass member so you can participate in the next live Q&A, or so you can have access to the complete recording and transcript of each Q&A session, you can save 10% off the subscription price for as long as you remain a member by using this link to sign up: https://chrismasterjohnphd.substack.com/qanda Learn more about the Masterpass here: https://chrismasterjohnphd.substack.com/about This snippet is from the July 13, 2022 AMA. The full recording and transcript is reserved for Masterpass members. Here is a preview of what's included: How do I know if my digestive enzymes are helping or hurting? Why does high-dose glycine give me these terrible symptoms? How to know if my magnesium is messing with my calcium? Why do I have vitamin A symptoms when my lab tests are normal What is my favorite web site for finding enzymatic cofactors Potassium citrate vs potassium chloride Major problems with B vitamin supplements Is food sensitivity testing useful? What nutrients might help with dihydropyrimidine dehydrogenase deficiency? Does lipoic acid hurt methylation? Sulfur SIBO that just won't go away. Using lactate, pyruvate, and ketone ratios to indicate the NADH/NAD+ ratio. Helping bile flow without pharmaceuticals. Managing pernicious anemia. Do we really need to meet the RDA for calcium? Could stretch marks be a sign of copper toxicity? When iron saturation is driven by low binding capacity. How do I know if I need methyl-free Bs? What causes heat intolerance? Here's a link to the full AMA: https://chrismasterjohnphd.substack.com/p/recording-and-transcript-of-the-june-de3 Access the show notes, transcript, and comments here . Chris Masterjohn, PhD, is the Founder and Scientific Director of the mitochondria test Mitome .