What is Vitamin D?

Vitamin D assists the body absorb calcium and phosphorus, and maintains healthy bones and teeth. The vitamin D (25-OH) test measures the degree of Vitamin D (25-OH) in the blood which is a beneficial indicator of osteoporosis (bone weakness), rickets (bone malformation), and osteomalacia.

Why is Vitamin D test performed?

To ascertain vitamin D deficiency when calcium concentration is low or a person has signs of vitamin D deficiency such as bone malformation in children (rickets) and bone weakness, softness, or fracture in adults (osteomalacia).

Before commencing medication for osteoporosis.

To observe the appropriateness of medication in patients who are receiving Vitamin Supplements, calcium, phosphorus, and/or magnesium supplements.

To diagnose/monitor problems with the parathyroid gland functioning knowing the parathyroid hormone (PTH) is necessary for vitamin D activation.

To observe the well-being of persons with diseases that meddle with fat absorption, such as cystic fibrosis and Crohn’s disease and in patients who have gone through gastric bypass surgery.

What does Vitamin D Measure?

Vitamin D Test measures the degree of Vitamin D in the blood. Two types of vitamin D can be measured in the blood, 25-hydroxyvitamin D and 1,25-dihydroxy vitamin D. The 25-hydroxyvitamin D is the main form discovered in the blood and is somewhat inactive precursor to the active hormone, 1,25-dihydroxy vitamin D. Because of its extended half-life and higher concentration, 25-hydroxy vitamin D is often times measured to determine and observe vitamin D status in persons.

The 25-hydroxyvitamin D test is performed to decide the degree of Vitamin D in your blood, whether it is low or higher than normal. A low degree can be detected if a person is not getting enough sunlight or sufficient dietary vitamin D to meet his or her body's demand or if there is a problem with its absorption from the intestines (cystic fibrosis, Crohn’s disease, who have gone through gastric bypass surgery). Sometimes, drug treatments used to treat seizures (Phenytoin) lead to Vitamin D deficiency by interfering with the transformation to 25-hydroxyvitamin D in the liver. Severe liver and kidney disease can as well result in vitamin D deficiency. A high degree shows excess supplementation of the vitamin.

INTERPRETING VITAMIN D RESULTS
A lower vitamin D degree than the normal reference range shows vitamin D deficiency which can be because of much less sunlight exposure, dietary deficiency or less absorption from the intestine.

A higher vitamin D degree than the normal reference range shows vitamin D intoxication and is typically due to excess supplementation of the vitamin.

Range:
The normal range of nutrition D is measured as nanograms per millilitre (ng/mL) or nmol/L and can differ from lab to lab.

Level Reference range (ng/mL)

Deficiency <20

Insufficiency 20-29

Sufficiency 30-100

Toxicity >100

Note: There can be seasonal variants in 25 (OH) vitamin D levels, with values being 40-50% lower in winter than in summer. It is also affected by sunlight, latitude, pores and skin pigmentation, sunscreen use, and hepatic function.

· 25 (OH)vitamin D range can vary with age

· 25 (OH) vitamin D degree is multiplied all through pregnancy.

FREQUENTLY ASKED QUESTIONS (FAQ’s)

Q. How is this check performed?
This test is carried out on a blood sample. A syringe with a first-rate needle is used to withdraw blood from a blood vessel in your arm. The healthcare practitioner will tie an elastic band around your arm to make the blood vessels swell with blood. This makes it simpler to withdraw blood. You may as well be requested to tighten your clenched fist. Once the veins are absolutely visible, the place is cleaned with an antiseptic solution and then the needle is inserted into the blood vessel to acquire the sample. You will sense a tiny pinprick for the duration of the procedure. Blood sample once taken will then be dispatched to the laboratory.

Q. Is there any preparation needed prior to the test?
Inform the healthcare provider about the medications you may be taking. No other specific preparations are normally needed prior to this test.

Q. What is Osteomalacia?
Osteomalacia is the softening of the bones due to demineralization (the loss of minerals) and is most observed by the depletion of calcium from bone. It is an attribute of vitamin D deficiency in adults. Osteomalacia can also be triggered with the aid of bad dietary consumption or terrible absorption of calcium and other minerals needed to harden bones.

Q. What are the sources of Vitamin D?
Vitamin D is obtained from endogenous sources and exogenous sources. Endogenous sources are produced in our body when our skin is exposed to sunlight. Whereas, exogenous sources can only be derived from other sources, as they are now not produced in our bodies. Dietary sources of vitamin D comprises of fish, eggs, solid dairy products, and dietary supplements.

Q. What does the Vitamin D test result mean?
A below-normal stage indicates vitamin D deficiency, it can manifest in conditions such as lack of exposure to sunlight, dietary deficiency of vitamin D, liver and kidney diseases, low food absorption in cystic fibrosis and Crohn’s disease, and in patients who have gone through gastric bypass surgery. Along with that, using some drugs such as phenytoin, phenobarbital, rifampin, etc. can lead to vitamin D deficiency. These reduced levels of vitamin D can also be found in babies who solely feed on breast milk. Such toddlers can be given formula milk, as it is fortified with vitamin D. An elevated degree of vitamin D is referred to as hypervitaminosis D or vitamin D toxicity. This is in many instances induced by way of taking too a great deal of vitamin D and can result in elevated or high calcium levels in the body (hypercalcemia). It can also cause kidney and blood vessel damage.

Q. Who should be tested (checked) for Vitamin D?
Vitamin D 25 (OH) should be tested in people who are presently going through medication to forestall or treat osteoporosis, and patients having signs and symptoms of low calcium level (hypocalcemia) or excessive calcium degree (hypercalcemia). It ought to be performed in patients with cystic fibrosis, Crohn’s disease, and with gastric bypass surgery, patients receiving vitamin D treatment who do not exhibit medical improvement. Along with that, these tests can be carried out in aged people, specifically people with minimal exposure to sunlight, younger people and adults with suspected rickets and osteomalacia, respectively, and babies who are completely breastfed.

Q. What are the factors which can influence the 25-OH Vitamin D levels?
There can be a number of factors that can affect 25-OH diet Vitamin D levels among Nigerians, some of them are defined below:

Seasonal variation: Ideally, all samples should be taken in one season. The reason is, that there can be seasonal differences in 25 (OH) vitamin D levels, with values being a 40-50% decrease in wintry weather than in summer. This can have an effect on the absorption rate of Vitamin D.

Age: Older adults have a reduced level of 7-dehydrocholesterol, so they cannot synthesise 25(OH) vitamin D. Along with that, the manufacturing of active hormone (1,25 dihydroxy Vitamin D3) gets decreased by their kidneys.

Skin colour: Melanin in the darker skin reduces the capacity to produce 25(OH) Vitamin D from sunlight exposure, as it absorbs the sunlight.

Body mass index/nutrition: Obese men and women (body mass index >30 kg/m2) are deficient in Vitamin D, as Vitamin D is fat-soluble. This is because it gets sequestered in the fat and will not be capable of circulating. As a result, the rate of absorption of Vitamin D remains low in chubby patients in contrast to other healthful individuals.

Certain drugs like phenytoin (seizure drug), phenobarbital, rifampin, cholestyramine, orlistat, steroids, and stimulant laxatives can reduce Vitamin D levels. Other than these, Vitamin D can be influenced through sunlight, latitude, sunscreen use, and hepatic function.

Q. What is osteoporosis?
Osteoporosis among Nigerians is a circumstance of fragile bones with accelerated susceptibility to fracture. Vitamin D and calcium deficiency are one of the main causes of osteoporosis. Other causes can be genetics, lack of exercise, non-public records of fracture as an adult, cigarette smoking, excessive alcohol consumption, history of rheumatoid arthritis, low body weight, and family history of osteoporosis. Usually, osteoporosis does not happen by itself until bone fractures occur. X-rays and bone mineral density tests can assist diagnose osteoporosis.