Symptoms of Vitamin D Deficiency: How Do You Tell?
Fatigue, Muscle Pains, and Weight Changes
Medically reviewed by Kashif J. Piracha, MD
Vitamin D deficiency is the most common nutritional deficiency in the world. You might become deficient if you don't get enough vitamin D through diet or exposure to sunlight. There are also a few health conditions and medicines that make it harder for your body to produce vitamin D.
Low vitamin D levels can cause muscle weakness, fatigue, hair loss, and other symptoms. Vitamin D affects most body systems and is important to overall health. Even so, you may not notice symptoms.
This article discusses vitamin D deficiency symptoms, how to find out if you're deficient, and why some people are asymptomatic (have no symptoms).
Who Gets Low Vitamin D Levels?
Among those most likely to have a vitamin D deficiency are:
Babies who are exclusively fed human milk
People with limited exposure to sunlight, such as those who can't go outside or those who cover all their skin
Older adults because as you age, your skin doesn't synthesize vitamin D from sunlight exposure as well
People with dark skin, which makes it harder to make vitamin D from sunlight exposure
People with obesity or those who have had gastric bypass surgery
Vitamin D is a fat-soluble vitamin. If your gut doesn't absorb fat well, this interferes with absorbing vitamin D dissolved in fat in the diet. Conditions that can interfere with this process include:
Some liver and kidney diseases
Certain drugs that may affect vitamin D levels include:
Some cholesterol medications, including Altoprev (lovastatin), Lipitor (atorvastatin), and Zocor (simvastatin)
Steroids, including prednisone
Weight-loss medicines Xenical and alli (orlistat)
Some anti-seizure medications, including Dilantin (phenytoin), phenobarbital, and Tegretol (carbamazepine)
Being Asymptomatic With Vitamin D Deficiency
Most people with vitamin D deficiency are asymptomatic. However, it's easy to overlook nonspecific symptoms or attribute mild symptoms to something else. 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 Deficiency Symptoms
Your body needs vitamin D to absorb calcium, and calcium is crucial to bone health. Vitamin D is also important to muscles, the nervous system, and the immune system.
Symptoms of vitamin D deficiency can include:
Sleep problems
Exhaustion, fatigue
Bone pain or achiness
Muscle pain
Muscle weakness
Muscle twitches, tremors, or spasms
Sadness, depression
Mood changes
Hair loss
Lack of appetite
Pale skin
Tingling in the hands and feet
Getting sick easily
Vitamin D may not have a direct effect on weight changes. However, related contributing factors may play a role in weight loss or gain, including:
Symptoms such as loss of appetite and fatigue
Certain medical conditions and medications
Obesity, weight loss medications, and weight loss surgery
Health Effects of Low Vitamin D
You might be deficient in vitamin D due to diet, lack of sun exposure, or because of certain health conditions or medicines. It's important to get a diagnosis and initiate treatment because severe vitamin D deficiency in children can cause rickets, a condition that leads to:
Bone deformities
Stunted growth
Fragile bones that are easily fractured
In adults, severe vitamin D deficiency can lead to:
Osteomalacia: Softening of the bones, which is the adult version of rickets
Osteopenia: Low bone density, a precursor to osteoporosis
Osteoporosis: A condition characterized by weak, brittle bones that are easily fractured
Vitamin D deficiency is also associated with chronic diseases that may include:
Cancer
Heart disease
Diabetes
Immune system diseases
Neuropsychiatric disorders
How to Test for Low Vitamin D
You can determine vitamin D levels with a blood test called 25-hydroxyvitamin D. It's not a routine test, but a healthcare provider might recommend it if you're at high risk of vitamin D deficiency or have symptoms.
Test results report vitamin D as measured by the 25-hydroxy level in nanomoles per liter (nmol/L) or nanograms per milliliter (ng/mL) as follows:
Deficiency: less than 30 nmol/L (12 ng/mL)
Inadequate: between 30 nmol/L (12 ng/mL) and 50 nmol/L (20 ng/mL)
Adequate: between 50 nmol/L (20 ng/mL) and 125 nmol/L (50 ng/mL)
High that can be associated with adverse effects: higher than 125 nmol/L (50 ng/mL)
Ruling Out Other Causes
The symptoms of vitamin D deficiency overlap with those of many other conditions. For example, symptoms such as muscle weakness, fatigue, and sleep problems can look like chronic conditions, including multiple sclerosis (MS) and fibromyalgia. Symptoms such as poor appetite, sadness, and mood changes might mimic a mood disorder like depression.
It's important to report all symptoms to a healthcare provider so they can determine the next steps to rule out or confirm the diagnosis.
Initiating Treatment for Symptoms of Vitamin D Deficiency
Your vitamin D needs change with age. The recommended amounts in international units (IU) are:
Birth to 1 year: 400 IU
Age 1 to 70, including those who are pregnant or lactating: 600 IU
Age 71 and older: 800 IU
You can get vitamin D fairly quickly by taking dietary supplements. 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.
You can also increase vitamin D through diet or by increasing sun exposure. However, your provider may not recommend extra sunlight because of the long-term risk of skin cancer.
When it comes to diet, not many foods contain vitamin D, though many are fortified with it. Some good food sources are:
Cod liver oil
Fatty fish such as trout, salmon, tuna, and mackerel or sardines
Raw, white mushrooms exposed to ultraviolet (UV) light
Eggs
Beef liver
Foods fortified with vitamin D include:
Most milk, including cow, almond, and soy
Breakfast cereals
Orange and other juices
A healthcare provider may recommend other therapies, depending on your diagnosis and overall health.
You are unlikely to get too much vitamin D through diet or sunlight. However, when taking supplements, keep in mind that the tolerable upper limit (UL) per day is:
Birth to 6 months: 1,000 IU
Age 7 months to 1 year: 1,500 IU
Age 1 to 3: 2,500 IU
Age 4 to 8: 3,000 IU
Age 9 and up: 4,000 IU
Taking more increases the risk of toxic effects. Too much vitamin D can cause high calcium blood levels (hypercalcemia), which can damage the kidneys, soft tissues, and bones. Symptoms include:
Poor appetite
Excessive thirst
Passing more frequent and larger amounts of urine than normal
Dehydration
Constipation
Irritability, confusion
Fatigue
Muscle weakness
Vomiting
High blood pressure
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 can find out if you're vitamin D deficient with a blood test. If you are deficient, it's very treatable. Dietary supplements can get your vitamin D level up fairly quickly, but don't take more than your healthcare provider recommends.
Any further treatment will depend on your overall health and if you have related conditions.
Read the original article on Verywell Health.