Vitamin D

Vitamin D Deficiency: Know the Causes, Symptoms, and Treatment

Vitamin D is an essential nutrient to maintain healthy bones and teeth. It also plays a critical role in the proper functioning of the immune system. Despite the importance of this vitamin, many people suffer from vitamin D deficiency. Today, we will talk about the causes, symptoms, and lab tests used to diagnose vitamin D deficiency.

Causes of Vitamin D Deficiency 

There are several reasons why a person may develop vitamin D deficiency. One of the most common reasons is a lack of exposure to sunlight. The body produces vitamin D when the skin is exposed to sunlight. However, people who live in areas with limited sunlight or who spend most of their time indoors may not get enough of it from sunlight alone. Other factors that can contribute to vitamin D deficiency include a poor diet, certain medical conditions, and certain medications.

Symptoms of Vitamin D Deficiency

Vitamin D deficiency can cause a wide range of symptoms, including bone pain, muscle weakness, fatigue, and depression. In severe cases, it can also lead to the development of rickets in children and osteomalacia in adults. Rickets is a condition that causes soft and weak bones, while osteomalacia weakens bones and muscles.

Lab Tests for Vitamin D Deficiency

A lab test can be used to diagnose deficiency. One of the most common tests is the 25-hydroxyvitamin D blood test, which measures the level of vitamin D in the blood. A level of less than 20 nanograms per milliliter (ng/mL) is considered deficient, while those between 20 and 30 ng/mL are considered insufficient, while levels greater than 30 ng/mL are considered adequate.

Another lab test that can be used is the parathyroid hormone (PTH) test. PTH is a hormone produced by the parathyroid gland in response to low levels of calcium in the blood. When vitamin D levels are low, the body may produce more PTH to increase calcium absorption. A high level of PTH in the blood can indicate deficiency.

Finally, a bone density test can be used to diagnose vitamin D deficiency. This test measures the density of bones and can help identify bone loss due to conditions such as osteoporosis or osteomalacia, which can be caused by vitamin D deficiency.

Treatment for Vitamin D Deficiency

Treating vitamin D deficiency typically involves taking supplements. The amount of vitamins needed to correct a deficiency will be based on the severity of the deficiency and other factors such as age and overall health. In some cases, high doses of vitamin D may be needed to correct a deficiency quickly.

However, you should note that taking too much of it can also be harmful. High levels of vitamin D can lead to a condition called hypercalcemia, which is characterized by high levels of calcium in the blood. This can cause various symptoms, including nausea, vomiting, and abdominal pain.

In addition to taking supplements, people with vitamin D deficiency can also increase their exposure to sunlight and improve their diet. You can take food rich in vitamin D such as egg yolks, fatty fish, and fortified foods like milk and cereal.


Vitamin D deficiency is a common condition that can cause a range of symptoms, including bone pain, muscle weakness, and fatigue. You can take a lab test and a bone density test to diagnose if you have a deficiency. Treatment typically involves taking vitamin D supplements and making lifestyle changes such as increasing exposure to sunlight and improving the diet. It is important to work with a healthcare professional to determine the appropriate treatment and to monitor vitamin D levels to ensure that they remain within a safe range.

For fast, affordable, and private lab testing, turn to RSC Health. We provide the shortest possible turnaround time and verify lab results to ensure accuracy. If treatment is needed, we offer follow-up consultations for your peace of mind. Contact us to get lab tests today.

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