High-fat diet reduces CYP2R1 gene needed to make semi-activated vitamin D (mice) – Aug 2021

• CYP2R1 (vitamin D 25-hydroxylase ) semiactivates vitamin D in many places in the body
• Poor CYP2R1 gene results in lower vitamin D and 2X increase in T1 Diabetes – Sept 2019
• CYP2R1 gene problem increases Multiple Sclerosis risk by 1.4X – Dec 2018
• CYP2R1 mutations also cause vitamin D-deficient rickets – July 2016
• Vitamin D insufficiency was 3.7 X more likely if CYP2R1 gene variation– June 2014
• Lung Cancer (NSLC) more lethal if poor Vitamin D gene ( CYP2R1) – Oct 2019
• Poor CYP2R1 gene reduces blood response to Vitamin D supplementation – Aug 2019
• Response to Vitamin D varied by 12 ng due to gene variants (CYP2R1) – Aug 2019
• GC and CYP2R1 genes associated with higher summer vitamin D levels – Jan 2013

One or both of the following causes of low Vitamin D in obese

1. High fat diet ==> lower vitamin D generated
   • abstract does not indicate strength of this reduction
2. High fat diet ==> increased obesity ==> more vitamin D stored in fatty tissue

CYP2R1 in Wikipedia

CYP2R1 is now known to be regulated, with variations in the expression and activity of CYP2R1 affecting circulating 25(OH)D.[9] Low levels of CYP2R1 activity have been found after 24 hour fasting, in obesity, type 1 and type 2 diabetes[12] and are decreased by glucocorticoids such as dexamethasone.[9] These conditions are known to be linked to low blood levels of 25(OH)D, where even large doses of vitamin D may not produce an improvement, which can be explained by enzyme activities being low.[9]

Some CYP2R1 studies on web

• Diet induced obesity modifies vitamin D metabolism and adipose tissue storage in mice - Jan 2019 FREE PDF
• Four days high fat diet modulates vitamin D metabolite levels and enzymes in mice - Jan 2021 $30
• Effects of high fat diet-induced obesity on vitamin D metabolism and tissue distribution in vitamin D deficient or supplemented mice June 2020 FREE PDF
• Obesity Represses CYP2R1, the Vitamin D 25-Hydroxylase, in the Liver and Extrahepatic Tissues - July 2020 FREE PDF

Genetics category listing contains the following

see also

• Vitamin D Receptor has 530 items
• Vitamin D Binding Protein = GC has 177 items
• CYP27B1 has 63 items
• CYP24A1 in title of 34+ items
• CYP2R1 25+ items
• Calcidiol has 48 items
• Calcitriol has 62 items
• Topical Vitamin D
• Nanoemulsion Vitamin D may be a substantially better form
• 1289 genes changed with higher doses of Vitamin D - RCT Dec 2019
• CYP3A4 (7 as of Dec 2022)
• Getting Vitamin D into your body
• 

Vitamin D blood test misses a lot

• Vitamin D from coming from tissues (vs blood) was speculated to be 50% in 2014, and by 2017 was speculated to be 90%
• Note: Good blood test results (> 40 ng) does not mean that a good amount of Vitamin D actually gets to cells
• A Vitamin D test in cells rather than blood was feasible (2017 personal communication)   Commercially available 2019
  • However, test results would vary in each tissue due to multiple genes
• Good clues that Vitamin D is being restricted from getting to the cells
  1) A vitamin D-related health problem runs in the family
      especially if it is one of 51+ diseases related to Vitamin D Receptor
  2) Slightly increasing Vitamin D shows benefits (even if conventional Vitamin D test shows an increase)
  3) DNA and VDR tests - 120 to 200 dollars $100 to $250
  4) PTH bottoms out ( shows that parathyroid cells are getting Vitamin d)
     Genes are good, have enough Magnesium, etc.
  5) Back Pain
     probably want at least 2 clues before taking adding vitamin D, Omega-3, Magnesium, Resveratrol, etc
  • The founder of VitaminDWiki took action with clues #3&5