Vitamin D affects most body systems and is important to overall health.

Symptoms of a vitamin D deficiency can include muscle weakness, fatigue, and hair loss.

That means some supplement products may not contain what the label says.

An illustration of a person who displays symptoms of vitamin D deficiency and a list of symptoms.

Illustration by Julie Bang for Verywell Health

Illustration by Julie Bang for Verywell Health

Who Gets Low Vitamin D Levels?

Among those most likely to have a vitamin D deficiency are:

Vitamin D is afat-solublevitamin.

Symptoms may not be apparent until there are complications.

For example, you may not know you have fragile bones until you experience a fracture.

Vitamin D is also important to muscles, the nervous system, and the immune system.

Symptoms of vitamin D deficiency can include:

Vitamin D may not have a direct effect on weight changes.

Symptoms such as poor appetite, sadness, and mood changes might mimic a mood disorder likedepression.

Initiating Treatment for Symptoms of Vitamin D Deficiency

Your vitamin D needs change with age.

Most multivitamins provide 400 IUs.Other supplements have just vitamin D or vitamin D with calcium.

Be sure to take the amount your healthcare provider recommends.

When it comes to diet, not many foods contain vitamin D, though many are fortified with it.

You are unlikely to get too much vitamin D through diet or sunlight.

Symptoms include:

Summary

Vitamin D deficiency is a common problem worldwide.

Symptoms include fatigue, muscle aches, and getting sick easily.

Severe vitamin D deficiency can lead to serious health issues, such as rickets and osteoporosis.

Lack of vitamin D may also play a role in immune system disorders, heart disease, and cancer.

you’ve got the option to find out if you’re vitamin D deficient with a blood test.

If you are deficient, it’s very treatable.

Any further treatment will depend on your overall health and if you have related conditions.

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