Blood test

Low vitamin D level in the blood

Blood test
Low vitamin D level in the blood
Last update: 27/05/2022

What is low vitamin D level in the blood called?

  • Vitamin D low

What is the normal level of vitamin D in the blood?

If you need to know which are the vitamin D reference ranges or you require more information about vitamin D in a blood test, you can visit normal vitamin D in a blood test.

What does a low vitamin D level in the blood mean?

Vitamin D is also known as the sunshine vitamin because it is synthesized by skin exposure to the sunshine.

Low values of vitamin D in the blood are common in winter, in aged people who do not get regular exposure to sunlight or in countries with few daylight hours.

A low level of vitamin D occurs with malabsorption syndromes such as celiac disease or cystic fibrosis. Also, in case of suffering nephrotic syndrome where there is a significant loss of vitamin D in the urine.

A prolonged and severe deficiency of vitamin D may alter the development of bones, causing rickets in children and osteomalacia in adults.

The most common vitamin D blood test measures only the 25-hydroxy vitamin D [25(OH)D] that it is the main circulating form of vitamin D.

Vitamin D [25(OH)D] blood values are usually given in ng/ml but sometimes you can see these values in nmol/l following the International System of Units (SI). In case your values are in nmol/l you can convert them using this tool:


A low vitamin D [25(OH)D] level in the blood means:

  • Moderate vitamin D decrease (20 - 30 ng/ml in adults):

    The vitamin D level [25(OH)D] in the blood is a bit low and it is advisable to monitor the level in future blood tests.

    It may be due to a low exposure to sunlight or a poor absorption of vitamin D.

    Some anticonvulsants (phenytoin or phenobarbital) or drugs used to treat tuberculosis (rifampicin) may reduce the vitamin D blood levels. Therefore, if you are taking medication you can ask your doctor about any possible interference.

  • Severe vitamin D decrease (< 20 ng/ml in adults):

    Vitamin D levels are very low and you should visit your doctor as soon as possible because a prolonged deficiency may cause rickets in children and osteomalacia in adults.

    Patients who have severe deficiency will most likely have a more complicated pathology that needs to be addressed.

Which factors can reduce the vitamin D level in the blood?

Some particular health situations or drugs may reduce your vitamin D [25(OH)D] level in the blood:

  • Insufficient sun exposure
  • Low intake of vitamin D on diet
  • Gastric surgery
  • Pregnancy
  • Drugs

Which diseases can reduce your vitamin D level in the blood?

The following diseases can explain a vitamin D [25(OH)D] blood level lower than normal:

  • Celiac disease
  • Short bowel syndrome
  • Sprue
  • Cystic fibrosis
  • Pancreatic insufficiency

What can I do to increase the vitamin D level in the blood?

You can elevate the vitamin D level in the blood if you increase the intake of foods rich in vitamin D. You can eat egg yolks, fatty fish (such as tuna or salmon), fortified dairy products or cod liver oil. Nevertheless, the most effective measure

is a regular sun exposure.

For those with a severe deficiency, the doctor may prescribe vitamin D supplements. Several types of oral and intravenous preparations are available.

In any case, it is necessary to get a proper diagnosis since it could be due to malabsorption or kidney problems that do not depend on the intake of vitamin D or the sun exposure.

Where can I find more information about vitamin D level in the blood?

You can visit our pages about:

Which values are considered a low vitamin D level in the blood?

The following values are considered to be above the normal range:

IMPORTANT: These levels are expressed in ng/ml. They are an example of a healthy adult of about 45 years old with no known disease with an adequate sunlight exposure and not taking any medication. The ranges can be different depending on the laboratory or on your personal circumstances.

Vitamin D
Moderate vitamin D decrease
29.9 ng/ml29.8 ng/ml29.7 ng/ml29.6 ng/ml29.5 ng/ml29.4 ng/ml29.3 ng/ml29.2 ng/ml
29.1 ng/ml29 ng/ml28.9 ng/ml28.8 ng/ml28.7 ng/ml28.6 ng/ml28.5 ng/ml28.4 ng/ml
28.3 ng/ml28.2 ng/ml28.1 ng/ml28 ng/ml27.9 ng/ml27.8 ng/ml27.7 ng/ml27.6 ng/ml
27.5 ng/ml27.4 ng/ml27.3 ng/ml27.2 ng/ml27.1 ng/ml27 ng/ml26.9 ng/ml26.8 ng/ml
26.7 ng/ml26.6 ng/ml26.5 ng/ml26.4 ng/ml26.3 ng/ml26.2 ng/ml26.1 ng/ml26 ng/ml
25.9 ng/ml25.8 ng/ml25.7 ng/ml25.6 ng/ml25.5 ng/ml25.4 ng/ml25.3 ng/ml25.2 ng/ml
25.1 ng/ml25 ng/ml24.9 ng/ml24.8 ng/ml24.7 ng/ml24.6 ng/ml24.5 ng/ml24.4 ng/ml
24.3 ng/ml24.2 ng/ml24.1 ng/ml24 ng/ml23.9 ng/ml23.8 ng/ml23.7 ng/ml23.6 ng/ml
23.5 ng/ml23.4 ng/ml23.3 ng/ml23.2 ng/ml23.1 ng/ml23 ng/ml22.9 ng/ml22.8 ng/ml
22.7 ng/ml22.6 ng/ml22.5 ng/ml22.4 ng/ml22.3 ng/ml22.2 ng/ml22.1 ng/ml22 ng/ml
21.9 ng/ml21.8 ng/ml21.7 ng/ml21.6 ng/ml21.5 ng/ml21.4 ng/ml21.3 ng/ml21.2 ng/ml
21.1 ng/ml21 ng/ml20.9 ng/ml20.8 ng/ml20.7 ng/ml20.6 ng/ml20.5 ng/ml20.4 ng/ml
20.3 ng/ml20.2 ng/ml20.1 ng/ml20 ng/ml    
Severe vitamin D decrease
19.9 ng/ml19.8 ng/ml19.7 ng/ml19.6 ng/ml19.5 ng/ml19.4 ng/ml19.3 ng/ml19.2 ng/ml
19.1 ng/ml19 ng/ml18.9 ng/ml18.8 ng/ml18.7 ng/ml18.6 ng/ml18.5 ng/ml18.4 ng/ml
18.3 ng/ml18.2 ng/ml18.1 ng/ml18 ng/ml17.9 ng/ml17.8 ng/ml17.7 ng/ml17.6 ng/ml
17.5 ng/ml17.4 ng/ml17.3 ng/ml17.2 ng/ml17.1 ng/ml17 ng/ml16.9 ng/ml16.8 ng/ml
16.7 ng/ml16.6 ng/ml16.5 ng/ml16.4 ng/ml16.3 ng/ml16.2 ng/ml16.1 ng/ml16 ng/ml
15.9 ng/ml15.8 ng/ml15.7 ng/ml15.6 ng/ml15.5 ng/ml15.4 ng/ml15.3 ng/ml15.2 ng/ml
15.1 ng/ml15 ng/ml14.9 ng/ml14.8 ng/ml14.7 ng/ml14.6 ng/ml14.5 ng/ml14.4 ng/ml
14.3 ng/ml14.2 ng/ml14.1 ng/ml14 ng/ml13.9 ng/ml13.8 ng/ml13.7 ng/ml13.6 ng/ml
13.5 ng/ml13.4 ng/ml13.3 ng/ml13.2 ng/ml13.1 ng/ml13 ng/ml12.9 ng/ml12.8 ng/ml
12.7 ng/ml12.6 ng/ml12.5 ng/ml12.4 ng/ml12.3 ng/ml12.2 ng/ml12.1 ng/ml12 ng/ml
11.9 ng/ml11.8 ng/ml11.7 ng/ml11.6 ng/ml11.5 ng/ml11.4 ng/ml11.3 ng/ml11.2 ng/ml
11.1 ng/ml11 ng/ml10.9 ng/ml10.8 ng/ml10.7 ng/ml10.6 ng/ml10.5 ng/ml10.4 ng/ml
10.3 ng/ml10.2 ng/ml10.1 ng/ml10 ng/ml9.9 ng/ml9.8 ng/ml9.7 ng/ml9.6 ng/ml
9.5 ng/ml9.4 ng/ml9.3 ng/ml9.2 ng/ml9.1 ng/ml9 ng/ml8.9 ng/ml8.8 ng/ml
8.7 ng/ml8.6 ng/ml8.5 ng/ml8.4 ng/ml8.3 ng/ml8.2 ng/ml8.1 ng/ml8 ng/ml
7.9 ng/ml7.8 ng/ml7.7 ng/ml7.6 ng/ml7.5 ng/ml7.4 ng/ml7.3 ng/ml7.2 ng/ml
7.1 ng/ml7 ng/ml6.9 ng/ml6.8 ng/ml6.7 ng/ml6.6 ng/ml6.5 ng/ml6.4 ng/ml
6.3 ng/ml6.2 ng/ml6.1 ng/ml6 ng/ml5.9 ng/ml5.8 ng/ml5.7 ng/ml5.6 ng/ml
5.5 ng/ml5.4 ng/ml5.3 ng/ml5.2 ng/ml5.1 ng/ml5 ng/ml4.9 ng/ml4.8 ng/ml
4.7 ng/ml4.6 ng/ml4.5 ng/ml4.4 ng/ml4.3 ng/ml4.2 ng/ml4.1 ng/ml4 ng/ml
3.9 ng/ml3.8 ng/ml3.7 ng/ml3.6 ng/ml3.5 ng/ml3.4 ng/ml3.3 ng/ml3.2 ng/ml
3.1 ng/ml3 ng/ml2.9 ng/ml2.8 ng/ml2.7 ng/ml2.6 ng/ml2.5 ng/ml2.4 ng/ml
2.3 ng/ml2.2 ng/ml2.1 ng/ml2 ng/ml1.9 ng/ml1.8 ng/ml1.7 ng/ml1.6 ng/ml
1.5 ng/ml1.4 ng/ml1.3 ng/ml1.2 ng/ml1.1 ng/ml1 ng/ml0.9 ng/ml0.8 ng/ml
0.7 ng/ml0.6 ng/ml0.5 ng/ml0.4 ng/ml0.3 ng/ml0.2 ng/ml0.1 ng/ml0 ng/ml
Medically reviewed by our Medical staff on 27/05/2022

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