Vitamin D 16.6 ng/ml means : causes, sources, risks, treatment

In this article we discuss what a Vitamin D value of 16.6 ng/ml means, what are its causes and how to calculate your Vitamin D deficiency risk score, and how to improve your Vitamin D as well as a treatment plan and possible risks.

What does a Vitamin D level of 16.6 mean?

A vitamin d level of 16.6 is considered to be deficient.

What is my Vitamin D level in SI units, for value of 16.6 in standard units?

In order to convert the value of Vitamin D from ng/ml into the SI Units, we must use a formula of conversion : Vitamin D in SI units (nmol/L) = Vitamin D in ng/ml*2.496¹ Based on the given formula, the value of Vitamin D in SI units for a value in ng/ml of 16.6 is 41.4 nmol/L

Is a Vitamin D value of 16.6 considered low or high?

Based on your Vitamin D value of 16.6. you are classified as having a moderate Vitamin D deficiency.

Vitamin D Levels

Category	Level (ng/mL)	Description
Severe Deficiency	< 10	Severely low vitamin D levels
Moderate Deficiency	10 - 20	Moderate Vitamin D Deficiency **You are here**
Insufficiency	20 - 30	Mild to Insufficient
Healthy	30 - 80	Normal Vitamin D Levels
Toxicity	> 80	Potentially harmful vitamin D levels

What are the sources of Vitamin D?

Food	How it helps with Vitamin D
Herring	Herring is a fatty fish that can contribute to Vitamin D intake.
Fortified dairy products	Milk, yogurt, and cheese are often fortified with Vitamin D to increase intake.
Sardines	Sardines are a good source of Vitamin D, especially when consumed with the bones.
Pork	Pork contains Vitamin D, particularly when sourced from pasture-raised animals.
Egg yolks	Egg yolks contain small amounts of Vitamin D, especially if the hens are raised on Vitamin D-enriched feed.
Canned salmon	Canned salmon, especially with bones, provides a convenient source of Vitamin D.
Fortified plant-based milk	Non-dairy milk alternatives (e.g., almond, soy) are often fortified with Vitamin D.
Mushrooms	Some mushrooms exposed to UV light can produce Vitamin D2.
Sunlight exposure	The skin produces Vitamin D when exposed to sunlight, specifically UVB rays.
Beef liver	Organ meats like beef liver contain Vitamin D, though levels can vary.

What are the causes of Vitamin D deficiency?

Cause	Description
Certain hormonal disorders	Hormonal imbalances can influence Vitamin D metabolism and its effects on the body.
Cystic fibrosis	Individuals with cystic fibrosis are at a higher risk of Vitamin D deficiency due to malabsorption.
Liver diseases	Liver disorders can affect the conversion of Vitamin D into its active form.
Crohn's disease	An inflammatory bowel disease that can lead to malabsorption and nutrient deficiencies.
Osteoporosis	Vitamin D is essential for bone health, and deficiency can contribute to conditions like osteoporosis.
Lack of fortified foods	A diet lacking in fortified dairy products or cereals may lead to lower Vitamin D intake.
Premature birth	Premature infants may have underdeveloped systems for producing and utilizing Vitamin D.
Dark skin	Higher melanin levels in dark skin reduce the skin's ability to produce Vitamin D from sunlight.
Certain genetic factors	Certain genetic variations can impact how the body processes and uses Vitamin D.
Strict vegan or vegetarian diet	Limited intake of animal products, which are sources of Vitamin D, can contribute to deficiency.

What symptoms will I experience with a Vitamin D of 16.6 ng/ml?

The symptoms of Vitamin D deficiency in children and adults are manifested by rickets and osteomalacia respectively. These conditions may show a variety of symptoms ranging from mild muscle pain, and bone pain to developmental abnormalities and fractures. For a Vitamin D level of 16.6 the symptoms are enlisted in the table below:

Vitamin D level 16.6 Symptoms in Children

Symptom	Description
Bone Pain	Children with rickets often complain of bone pain, which can be especially pronounced in the legs, pelvis, and spine.
Curvature of the Spine	Rickets can contribute to spinal deformities, such as scoliosis or kyphosis (excessive forward curvature of the upper spine).
Fractures	Due to weakened bones, children with rickets are more prone to fractures even with minor injuries.
Delayed Teething	Children with rickets might experience delays in the eruption of their teeth.
Enlarged Joints	Swelling and tenderness in the joints can occur as a result of rickets.
Irritability	Children with rickets might exhibit increased irritability and discomfort due to the physical pain they experience.
Bone Deformities	Rickets can lead to bone deformities, such as bowed legs or knock-knees, due to weakened bones unable to support the body's weight properly.
Delayed Growth	Children with rickets may experience slowed growth and development compared to their peers.
Difficulty Breathing	In severe cases, rickets can cause deformities of the ribcage, leading to difficulty in breathing and increased susceptibility to respiratory infections.
Wide Fontanelles	The soft spots on a baby's skull, known as fontanelles, might take longer to close in cases of rickets.

Vitamin D level 16.6 Symptoms in Adults

Symptom	Description
Bone Deformities	Osteomalacia can lead to bone deformities, such as bowed legs or a curvature of the spine.
Easy Bruising	Weakened bones and blood vessels can lead to easy bruising in individuals with osteomalacia.
Fractures	Brittle and weak bones due to osteomalacia increase the risk of fractures even with minor injuries.
Short Stature	In childhood cases, untreated osteomalacia can result in short stature and growth delays.
Frequent Infections	Impaired bone health can weaken the immune system, leading to an increased susceptibility to infections.
Difficulty Standing	Weak bones and muscles can make it challenging to stand for prolonged periods.
Bone Pain	Osteomalacia often leads to bone pain, particularly in the hips, lower back, and legs.
Dental Problems	Osteomalacia can affect the teeth, leading to enamel defects and other dental issues.
Bone Tenderness	Bones affected by osteomalacia can become tender to the touch.
Muscle Cramps	Deficiencies in bone mineralization and electrolytes can lead to muscle cramps and spasms.

What additional risks do I face with a Vitamin D level of 16.6?

Level	Risk
Your value is Less Than 25	Increased risk of fallsBischoff-Ferrari
Your value is Less Than 21	Increased risk of diabetes, hypertension, obesity and high triglyceride levelsMartins D

What is my Vitamin D deficiency score and how to calculate it?

Since your value of Vitamin D 16.6 is below the normal limit of 30, you must evaluate the following 4 factors that may be contributing to your deficiency. Based on a study done by Garg et al the following Vitamin D Insufficiency and Deficiency Score can predict and determine your causes of deficiency.

As per the study 4 major factors are invovled in Vitamin D deficiency.

Factors and Descriptions

Factor	Description
Physical Activity	Engaging in regular physical activity can contribute to improved metabolism and Vitamin D levels.
Obesity	Obesity, indicated by a body mass index (BMI) of 25 kg/m² or higher, can lead to Vitamin D deficiencies
Diet	Dietary intake of at least 100 Grams (gms) of milk/dairy products OR at least 100 gms fish or 1 egg with yolk for four or more days in the last seven days was considered Adequate
Daily Sun Exposure	Daily exposure to sunlight is important for the body's synthesis of Vitamin D. Spending at least 1.75 hours in the sun each day can help maintain Vitamin D levels, which is essential for bone health and immune function.

• Insufficiency Score for Vitamin D : 16.6

• You get less than 1.75 hours of sunlight per day
• AND
• Insufficient Dietary Intake + Obesity
• AND
• Obesity OR Insufficient Exercise
• Score : Your Vitamin D Insufficiency Score ranges between 14 - 18.

What is the treatment plan for a Vitamin D level of 16.6?

Vitamin D supplmentation is the only way to correct for deficiencies. The tables below list the dosages of Vitamin D supplements recommeded for different age groups, depending on the level of the Vitamin D. Since your value of Vitamin D is 16.6 the relevant supplement dosages are indicated below.^{Pawel Pludowski}

Recommended Daily Dosing for Vitamin D in cases where the Vitamin D Level is between 10 ng/dl and upto 30 ng/dl

A first line of treatment involves increasing the dosage to 1.5-2 x the current level of supplements if the patient is taking any supplements.

If you are not taking any supplements, the values in the table below are to be followed.

Age Group	Vitamin D Intake Per Day	Duration
Infants < 1 month	1000 IU/d	2 months
Infants 1–12 months	1000 IU/d	2 months
Children 1–11 yrs.	1870 IU/d **(Represents a value in the range of 1000 - 2000, must be adjusted as per patient.)	2 months
Children 11–18 yrs.	2319 IU/d **(Represents a value in the range of 2000 - 4000, must be adjusted as per patient.)	2 months
Adults	4000 IU/d	2 months

---