Vitamin D Deficiency: Causes, Symptoms, and Prevention

What is Vitamin D deficiency?

Vitamin D deficiency means that you are not getting enough of this vitamin in your body. You need Vitamin D for the growth and maintenance of your bones. You may be at risk of deficiency if you do not get enough sunlight on your skin, have a disorder that reduces your body’s ability to absorb it, or do not consume enough of it in your diet.

phosphorus is important for building and keeping strong bones. Vitamin D is used to treat and prevent bone disorders (such as rickets, osteomalacia). Vitamin D is made by the body when skin is exposed to sunlight. Sunscreen, protective clothing, limited exposure to sunlight, dark skin, and age may prevent getting enough vitamin D from the sun.Vitamin D with calcium is used to treat or prevent bone loss (osteoporosis). Vitamin D is also used with other medications to treat low levels of calcium or phosphate caused by certain disorders (such as hypoparathyroidism, pseudohypoparathyroidism, familial hypophosphatemia). It may be used in kidney disease to keep calcium levels normal and allow normal bone growth. Vitamin D drops (or other supplements) are given to breastfed infants because breast milk usually has low levels of vitamin D.

Also known as the sunshine vitamin, your body can produce it when your skin is exposed to sunlight. However, it is also found in certain foods, such as some fish, cod liver oil, egg yolks, as well as in fortified dairy products and orange juice.

Vitamin D3: What Are Its Benefits?

Vitamin D enhances calcium absorption and helps maintain adequate levels of calcium and phosphorus in the blood, which is essential for bone and dental health.

Vitamin D deficiency in children can lead to rickets, resulting in bowed legs due to softened bones, as well as dental issues such as improper tooth formation.

Similarly, in adults, vitamin D deficiency can manifest as osteomalacia. Long-term vitamin D deficiency can also lead to osteoporosis, or decreased bone density, which increases the risk of fractures.

What is Vitamin D and why does the body need it?

Vitamin D is essential for bone and dental health, immune function, brain health, and the regulation of inflammation. The body produces Vitamin D in response to sun exposure.

Certain foods and dietary supplements can also enhance Vitamin D intake. Despite its name, Vitamin D is not a vitamin but rather a hormone or prohormone.

In this article, we will explore the benefits of Vitamin D, what happens to the body when individuals do not get enough of it, and how to boost Vitamin D intake.

What is Vitamin D3?

$What is vitamin D deficiency? Vitamin D deficiency is the state of having inadequate amounts of vitamin D in your body, which may cause health problems like brittle bones and muscle weakness. There may be no symptoms and doctors don’t routinely check vitamin D levels, so many people are deficient and don’t realize it. Vitamin D helps the body absorb calcium and phosphorus, which are important to bone health. When a person is very vitamin D deficient, they cannot absorb dietary calcium well; having adequate levels is important to absorb enough calcium from your diet. Healthy vitamin D levels also help to improve phosphorus absorption from your diet. People typically get enough vitamin D from sun exposure: When sunlight hits the skin, the skin converts that ultraviolet radiation to vitamin D. People also get vitamin D from certain foods—including fish, egg yolks, and fortified milk and cereal—or dietary supplements. When vitamin D levels are low and the body isn’t able to properly absorb calcium and phosphorus, there is an increased risk of bone pain, bone fractures, muscle pain, and muscle weakness. In older adults, severe vitamin D deficiency (levels less than 10 ng/mL) may also contribute to an increased risk of falls.$

What is Vitamin D3?

Vitamin D3, also known as cholecalciferol, is a form of vitamin D. In fact, this vitamin exists in several forms, including:

Vitamin D2, which is synthesized by plants;

Vitamin D3, which, unlike D2, is of animal origin. It is synthesized by the skin and is the form we produce under the action of UV rays from the sun. It is also present in certain foods.

This vitamin does not have a direct action once absorbed and requires the liver and kidneys to become active and exert its effects on the body. It can then be stored in the muscles, liver, and adipose tissue.

Vitamin D3: What Benefits?

Vitamin D3 is essential for the proper functioning of our body, as it performs numerous functions.

Role in Calcification

Vitamin D3 enables proper calcium absorption and increases phosphorus concentration in the blood. Without it, calcium, even consumed in large quantities, cannot be deposited in the bones. Therefore, vitamin D3 contributes to the proper mineralization of the skeleton, joints, and teeth.

Through its action on calcium, vitamin D3 also plays a role in nerve transmission and muscle contraction.

Additionally, due to its role in calcification, vitamin D3 has a particularly important effect in infants by preventing rickets, and in the elderly, where it is essential for preventing osteoporosis and muscle weakness.

Role in the Immune System

Vitamin D3 helps strengthen immune defenses, particularly during the winter months when sunlight exposure decreases and vitamin D3 levels drop. Its action in the body plays a role in the prevention of certain diseases such as:

Easier Diabetes Stabilization

Vitamin D3 promotes the action of insulin, thereby facilitating easier stabilization of diabetes.

Vitamin D3 and the Happiness Hormone

Vitamin D3 plays a role in the synthesis of serotonin (the happiness hormone). A deficiency may therefore be linked to mood and notably depression.

Where can we find vitamin D?

Vitamin D3 is found in several foods. The most important sources are:

Fatty fish such as salmon, herring, sardines, and mackerel;
Cod liver oil;
Eggs;
Organ meats;
Dairy products;
Butter;
Mushrooms.

Additionally, there are many dietary supplements available in various forms. One should not forget that exposure to sunlight allows for the synthesis of this vitamin.

Vitamin D3 Deficiency: What Are the Impacts?

A deficiency in vitamin D3, or vitamin D, is quite common. There are various at-risk groups for vitamin D3 deficiency:

- Infants;
- Elderly individuals;
- Pregnant women;
- Patients with chronic diseases, osteoporosis, or diabetes.

Additionally, since this vitamin is primarily found in animal-derived products, vegetarians also represent an at-risk population.

Impacts of Vitamin D3 Deficiency

A deficiency will exacerbate the progression of osteoporosis and sarcopenia in the elderly, often leading to more frequent falls.

More generally, a lack of vitamin D3 manifests as:

- Fatigue;
- Muscle weakness;
- Low mood;
- Cramps;
- Weakened immunity, making individuals more susceptible to illnesses like the flu, etc.

Causes of Vitamin D Deficiency:

$What causes vitamin D deficiency? People who don’t have adequate levels of vitamin D may be deficient for any of these reasons: Not enough exposure to sunlight Darker skin pigment Malnutrition Kidney or liver failure, which prevents the body from adequately processing vitamin D Certain medications Certain types of cancer, such as lymphoma A family history of vitamin D deficiency or childhood rickets “It is important to note that ‘normal’ vitamin D levels have largely been determined in Caucasian populations. African Americans tend to have lower levels of vitamin D. Much of vitamin D in the blood is bound to carrier proteins, but emerging evidence indicates that when the “free,” unbound fraction of vitamin D is measured, it tends to be lower as well,” say Drs. Insogna and Carpenter. “Therefore, defining vitamin D deficiency in this population requires a consideration of other factors, such as the levels of parathyroid hormone in the blood and the levels of calcium in blood and urine.” Additionally, some people have health conditions that make it difficult for them to absorb vitamin D, including: Inflammatory bowel disease (Crohn’s disease or ulcerative colitis) Celiac disease Cystic fibrosis People who have had bariatric surgery for weight loss People who have had sections of the small intestine removed (resection) A condition affecting the pancreas, such as exocrine pancreatic insufficiency It has been suggested that vitamin D deficiency may play a role in certain conditions, such as fibromyalgia, chronic fatigue syndrome, and multiple sclerosis. However, a firm causal link between vitamin D deficiency and these—and other—conditions, along with the therapeutic benefits of vitamin D supplementation, has yet to be established.$

Causes of Vitamin D Deficiency

Although the body can produce vitamin D from sunlight, some individuals experience a deficiency. Factors that can influence this include:

Limited sun exposure: Individuals living in northern climates or areas with high pollution may not receive as much vitamin D as others. Those who work night shifts or do not go outside may also be at risk for deficiency.

Skin color: Skin pigmentation reduces the body’s ability to absorb ultraviolet B (UVB) rays. People with darker skin tones produce less vitamin D from sunlight compared to those with lighter skin.

Age: The skin's ability to synthesize vitamin D decreases with age. Older adults may also spend more time indoors.

Breastfeeding: Infants cannot obtain sufficient vitamin D from breast milk alone. The American Academy of Pediatrics recommends that exclusively and partially breastfed infants receive 400 international units (IU) of vitamin D orally each day until weaning. After weaning, they should receive at least 1000 mL daily of vitamin D-fortified formula or whole milk. Children who receive less than this, or who are not breastfed by caregivers, should take vitamin D supplements at a dose of 400 IU.

Certain medical conditions: Vitamin D is fat-soluble, meaning its absorption depends on the intestine's ability to absorb dietary fats. Conditions that limit fat absorption can reduce vitamin D intake from the diet.

Gastric bypass surgery: This surgery bypasses a portion of the upper intestine that absorbs large amounts of vitamin D. This bypass can lead to a deficiency of this vitamin.

How can I prevent vitamin D deficiency?

The best way to prevent vitamin D deficiency is to ensure you are getting enough vitamin D in your diet and/or through sun exposure. However, be cautious about staying in the sun for too long without using sunscreen. Excessive sun exposure increases your risk of developing skin cancer.

The amount of vitamin D you need each day depends on your age. The average recommended daily amounts are listed below in micrograms (mcg) and international units (IU).

There are some foods that naturally contain vitamin D, including:

- Fatty fish such as salmon, tuna, mackerel, and sardines.
- Trout.
- Beef liver.
- Mushrooms.
- Egg yolks.
- Cod liver oil.

You can also obtain vitamin D from fortified foods. Be sure to check nutrition labels to see if the food contains vitamin D. Foods that often have added vitamin D include:

- Cow's milk, soy milk, almond milk, and oat milk.
- Breakfast cereals.
- Orange juice.
- Other dairy products, such as yogurt.

Vitamin D is found in many multivitamins. There are also vitamin D supplements available.

Talk to your healthcare provider if you are concerned about getting enough vitamin D.