Toggle Health Problems and D

Reasons for low response to vitamin D

~ 50% of all people have a low response to vitamin D3
~ 10% of all people have a ZERO response to a LOW dose

There are 40+ reasons for poor blood response
Here are some of the common reasons

Obese   Elderly   Poor gut2X more needed
or gut-friendly
Health problem reduces levels    examples
Autism, Anemia, Diabetes Some Cancers
2X more needed
Fail to take with the largest meal1.3X more needed
Low Magnesium, smoking1.3X more needed


OccurrenceReason for low responseTypical %
extra Vit D
CommonExcess BMI/weight150% Obese need 2X to 3X more
CommonVitamin D supplement was not
taken with/after large meal
40%Take after large meal - provides more gut-time for vitamin D
evening meal or largest meal Note: avoid late in the evening
CommonMagnesium - low
(Gut needs Mg to absorb Vit. D)
30%Many reasons - which include low stomach acid and antacids
CommonSmoking30% Smoking reduces vitamin D -9 ng reduction
Commonmono-unsat fat ratio -low20%Need higher ratio of mono to poly fat ratio
CommonCola - soft drinks20%Cola removes Calcium, Vit D consumed in restoring Calcium
Common Oil-based Vitamin D 20%Oil-based Vitamin D helped the least
Some olive oils decrease absorption by 25 %
Bio-Tech uses a water-soluble form of Vitamin D
CommonVitamin K2 -low10% Overview Vitamin K and Vitamin D
perhaps 100 microgram/ 1000 IU of vitamin D
CommonBoron - low15%Boron increases vitamin D in the blood claims 6 mg ==> 24%
  -Boron is also known to build bone - perhaps by increasing vitamin D
CommonCholesterol - reduced in dietN.A.Cholesterol is needed to make Vitamin D from the sun
Low Cholesterol DOES NOT appear to affect vitamin D supplementation
- - - - -
SometimesExtremely Vit D deficient200%Low dose can result in ZERO increase if very deficient
When body is very deficient all vit. D is immediately consumed
Note: sometimes extreme deficiency is due to genes.
SometimesHealth - low200%Unhealthy body consumes a lot of vitamin D - see extremely deficient
(Examples: MS, HIV, some cancers, Diabetes, Depression. .
SometimesAnemia 40%Liver is needed to process vitamin D
Sometimes need to add Iron as well as vitamin D
SometimesFatty Liver40%Half of seniors have fatty liver, vitamin C reduces inflammation,
Calcidiol or Calcitriol might be taken instead of Vitamin
SometimesDrugs which consume
or block Vit D
50%Taking drugs such as Statins, Antiseizure, Prednisone, AIDS drugs,
Orlistat, Questran, Dilantin, Phenobarbital, Rifampin, Methamphetamine..
SometimesGenes50%Genes need to be functioning properly to process vitamin D
Twin studies   Genetics    VDBP    CYP2R1  also kidney
Note: sometimes cells do not get Vitamin D even though tests are OK
   see below on this page
SometimesTaking D2 vs D330% Sometimes D2 will actually DECREASE the level of D3
Note: D2 has a short half-life and should be taken daily
SometimesToo much UVA vs UVB20%UVA appears to actually DECREASE vitamin D levels
Avoid getting a lot of sun thru windows or very early/late in the day
SometimesWinter birth11%Winter birth, 11 % more likely to be vitamin D deficient as an adult
SometimesOral contraceptives
INCREASE response
-20% Oral Contraceptives INCREASES vitamin D levels
Perhaps due to less blood loss/anemia
SometimesTest results inaccurate+20% -20%Overview  Graph of tests from 1000 labs
Vitamin D differences of 5 ng are meaningless - Aug 2015
SometimesGut - poor100%Bio-Mulsion form of vitamin D was designed for poor guts
Topical Vitamin D bypasses the gut
SometimesProbiotic + - +20% -30% 1/3: 30% increased D bioavailability; 1/3: 20% decreases
SometimesDDT, pesticides20%Pesticides - 2016
SometimesPlastics (phthalates and BPA)10% 2016
SometimesVitamin A - excessive 30%Attenuates responses for > 10,000 IU vit D: from cod liver oil or Accutane
Many children in developing countries get excess Vit A doses every 6 months
SometimesRoundup/glyphosate ? %Gut bacteria and liver
SometimesStress ? %Cortisol consumes Cholesterol needed to make Vitamin D
SometimesAutism 100%Autistics have half of the response to Vitamin D (perhaps poor genes) – RCT Oct 2018
- - - - -
RareGallbladder removed
600,000/year in US
100%Gallbladder essential to absorb vitamins dissolved in fats
Consider other forms of Vitamin D: Biomulsion, water soluble
Also lipase to improve fat digestion
RareBariatric Surgery
which bypasses the small intstine
> 200%?Vitamin D is normally adsorbed only in the small intestine
will need to get alternate source of Vitamin D
RarePancreatic Insufficiency ??Fat soluble vitamins (A, D, E, K) are not absorbed as well
Also lipase to improve fat digestion
RareLiver problems50%Use Calcidiol or Calcitriol forms of vitamin D instead
Rare Burned skin 70% Burn - uncertain response to supplementation
- - - - -
Sun/UVSkin - Dark 250% vitamin D produced varies with darkness of skin: White = 0%, Black = 250%
Sun/UVSkin - Elderly 100% varies with age: teenager = 0%, 60 years = 100%
this due to thin skin or low cholesterol in skin
Sun/UVSkin - Sunburned 30% varies with % of skin which is burned
Burns and bone loss    75% less
- - - - - Reduction in Vitamin D actually getting to cells - downstream from Vitamin D Testing
Test invisibleGenes Genes, problems which often run in families
Vitamin D Receptor 405 items as of Aug 2021
Vitamin D Binding Protein 145 items as of Aug 2021
CYP27B1 37 items as of Aug 2021
Test invisibleCells Low Magnesium
Test invisibleCells Low Omega-3
Test invisibleKidney Poor Kidney


  • Any study will rarely consider even 4 of the above factors
  • Factors are sometimes additive: example, 50% + 50% = 100% = 2X as much Vitamin D is needed

Reasons for not getting benefits - even if blood tests are OK

click on image for details    See also Kidney   Low Magnesium, Low Omega,   Vitamin D Receptor    Vitamin D Binding Protein.

See also VitaminDWiki

Wide range in the responses after 1 year (black dots)
  Example: 2400 IU dose: 75-140 nmol response (30-56 ng)
  Example:  400 IU dose: 50-110 nmol response (20-44 ng)

Big differences between UVB response too 20-36 ng at 6 weeks


Alternate sources of vitamin D click on chart for details

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Created by admin. Last Modification: Friday January 21, 2022 18:45:29 GMT-0000 by admin. (Version 240)
Reasons for low response to vitamin D        
28940 visitors, last modified 21 Jan, 2022,
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