OPTION A:
If Vitamin D3 (WBC) is low and Vitamin D3 (Serum) is normal/excess:
Short term, status of micro nutrients is optimal, but cellular absorption may be a problem.
Recommend interventions:
- increase dietary intake of nutrient
- increase supplementation dosage
- consider status of synergistic nutrients for cellular absorption
- consider levels of oxidative stress on nutrient depletion
- consider follow-up testing to identify the source of my absorption.
OPTION B:
If Vitamin D3 (WBC) is low and Vitamin D3 (Serum) is low as well:
Short term and long term status of micro nutrients is not optimal, suggesting low dietary intake, and both intestinal and cellular absorption as possible causes.
Recommended interventions:
- Increase dietary intake of nutrient
- Increase supplementation dosage.
- Medications may have an effect on depletion
- Consider follow up testing to identify the source of malabsorption.
Clinical Manifestations of Depletion:
Conditions associated with low vitamin D status include: Alzheimer’s disease, asthma, autism, cancer, cavities,colds and flus, cystic fibrosis, dementia, depression, diabetes 1 and 2, eczema and psoriasis, hearing loss, heart disease, hypertension, infertility, inflammatory bowel disease, insomnia, macular degeneration, migraines, multiple sclerosis, Crohn’s disease, muscle pain, obesity, osteomalacia, osteoporosis, periodontal disease, preeclampsia, rheumatoid arthritis, schizophrenia, seizures, septicemia, and tuberculosis.
Reasons for suboptimal vitamin D3 levels include lack of sun exposure (particularly in northern latitudes and during the winter season), malabsorption (due to Celiac disease, or other inflammatory digestive disorders), inadequate hepatic vitamin D 25-hydroxylase enzyme activity, and some prescription medications such as antiepileptic drugs, including phenytoin, phenobarbital, and carbamazepine, that increase 25-OHD metabolism.
Levels of PTH may be high-normal or elevated in sub-clinical and frank vitamin D deficiency.
Food Sources:
Food sources of vitamin D include: dairy products, such as fortified milk and yogurt, fortified orange juice, egg yolks, liver, fatty fish, such as salmon, tuna, mackerel, sardines, shrimp, mushrooms grown in adequate sunlight, baker’s yeast.
Naturally occurring sources will contain vitamin D3, whereas fortified sources (baker’s yeast) will contain D2
Supplement Options:
- The previously established RDA of 400IU/day has been found to be insufficient for therapeutic needs. Common doses are used between 1000 and 10,000 IU/day.
- Vitamin D comes in two forms: D2 (ergocalciferol) and D3 (cholecalciferol); both forms can be used as active vitamin D3 (cholecalciferol) in the body, as D2 can be converted to D3 when needed, however, this is a tightly controlled metabolic process in order to prevent excess D2 to D3 conversion.
- Vitamin D is produced endogenously when skin is exposed to ultraviolet light from the sun.
- Supplementation with Vitamin D is almost always necessary, as it is extremely difficult to meet needs through diet and sun exposure alone. Consult with your practitioner for supplement recommendations and target goal for serum levels.
- Because vitamin D can be stored or trapped in adipose tissue (fat cells), obese individuals and pregnant women have higher vitamin D requirements.
- Obtaining too much vitamin D from sun exposure is not possible, but it is possible to obtain too much from supplementation.
- Taking too much vitamin D in supplement form can also cause an increase in blood levels of calcium, or hypercalcemia, due to increased intestinal absorption of calcium when serum vitamin D levels are high.
- Supplementing vitamin K2 alongside vitamin D is recommended in order to keep blood levels of calcium in homeostasis and prevent excess bone demineralization of calcium with higher vitamin D intake.
Vitamin D3 is also referred to as 1,25-hydroxyvitamin D3 (1,25-OHD3).
1,25-OHD3 has a shorter half-life in the blood than 25-OHD (what most standard labs run, and what is most commonly used to assess total vitamin D status), and, therefore, levels may differ from what is measured as 25-OHD.
The conversion of 25-OHD to 1,25-OHD is performed in D the kidneys and regulated by parathyroid hormone (PTH).
When blood calcium levels fall, PTH signals the kidneys to convert more 25-OHD to 1,25-OHD, which increases intestinal absorption of calcium, and reduces bone demineralization of calcium.
Vitamin D3 also regulates the function of hundreds of genes, supports the immune system, supports production and function of endocrine hormones, is important for normal growth and development of bones and teeth, tightly regulates the levels of calcium and phosphorus being absorbed intestinally as well as released from bone, regulates cell differentiation and growth, and may play an important role in regulating mood.
Patients who present with hypercalcemia, hyperphosphatemia, and low PTH may suffer from unregulated conversion of 25-OHD to 1,25-OHD.
Vitamin D3 (WBC)
