One of the fat soluble vitamins, vitamin D is produced on exposure of skin to sunlight. Vitamin D is required for strong bones as it helps your body in absorbing the dietary calcium. Vitamin D also helps in supporting health of muscles, in reducing inflammation which may result in diseases such as cancer and rheumatoid arthritis, in supporting heart health and regulating blood pressure.

What’s Considered Low Vitamin D Levels?

The most accurate method to measure the level of vitamin D in the body is the blood test referred to as 25-hydroxy vitamin D test. A level between 20 ng/ml (nanograms/milliliter) and 50 ng/ml is regarded healthy. A level below 12 ng/ml is an indication of deficiency of vitamin D.

What Are the Causes of Vitamin D Deficiency?

1. Lack of consumption of recommended intake of vitamin D over time: Deficient intake usually occurs in case you are following a strictly vegan diet as the vitamin is mostly present in animal based foods.
2. You have a limited exposure to sunlight: Since vitamin D is produced by the body on exposure of skin to sunlight, you may become deficient in the vitamin in case you remain indoors most of the time, reside in areas falling under northern latitudes (these areas have less access to UVB rays of sun), wear head coverings or long robes due to religious reasons or are in an occupation where there is limited exposure to the sun.
3. You are dark skinned: The melanin pigment decreases the ability of the skin to produce vitamin D when exposed to sunlight. According to studies, elderly people who have darker skin have greater risk of developing deficiency.
4. Your kidneys are not able to convert the vitamin to the form that is active: As you get older, the kidneys decrease in function; thereby, increasing your risk of developing deficiency of vitamin D.
5. Vitamin D is not absorbed adequately by your digestive system: Certain diseases such as cystic fibrosis, celiac disease and Crohn’s disease may affect the ability of your intestines to adequately absorb the vitamin; thereby, resulting in deficiency of the vitamin.
6. You are overweight or obese: According to research, being overweight or obese is linked to lower levels of Vitamin D. This may occur because absorption of vitamin D is affected somehow by excess fat present in the body.
7. You live in area that is highly polluted: Sun’s rays may be absorbed by pollution particles; thereby, reducing your exposure.
8. You use large amounts of sunscreen: Using large amounts of sunscreen on your body to block the UV rays may reduce levels of vitamin D; however, very few individuals utilize enough sunscreen that fully blocks UV rays.
9. Liver and kidney health: Individuals suffering from kidney or liver disease are more prone to have lower levels of vitamin D.
10. Pregnancy or lactation: The demands of a fetus or an infant may reduce the levels of vitamin D, especially in females who are already prone to develop vitamin D deficiency.

Symptoms and Signs of Deficiency of Vitamin D

The symptoms of deficiency may be vague, may change with time and resemble symptoms of many ailments. Hence, you should not self-diagnose deficiency of vitamin D. Persons who notice symptoms of a deficiency should have a test. Some symptoms and signs of deficiency of vitamin D are:

1. Frequent infections

Vitamin D has an important role to play in maintaining the strength of your immune system. This helps in fighting off the bacteria and viruses. Hence, low levels of vitamin D are associated with frequent infections, particularly of the respiratory tract such as colds, pneumonia and bronchitis.

2. Tiredness and fatigue

Excessive tiredness and fatigue even with plenty of sleep may indicate deficiency and energy levels may be improved by consuming supplements.

3. Back and bone pain

Lower back and bone pain (in ribs, joints and legs) is another symptom of vitamin D deficiency as vitamin D has a key role to play in supporting the health of bones. 

4. Depression

A link has been found between low levels of vitamin D and anxiety and depression in studies. Furthermore, it has been found in some studies that the mood improves by taking supplements.

5. Impaired healing of wounds

Low levels of vitamin D may result in poor healing of wounds following injury, infection or surgery as it has been found that vitamin D has a role to play in fighting infection and controlling inflammation for proper wound healing.

6. Bone loss

Low levels of vitamin D may lead to bone loss or reduced bone mineral density resulting in brittle or thinning of bones, osteoporosis and frequent fractures of bones. Hence, you should maintain adequate intake of vitamin D to preserve bone mass and reduce your risk of fracture especially as you age.

7. Muscle pain and weakness

According to studies, a link exists between low levels of vitamin D and chronic pain. The reason is the interaction between nerve cells which sense pain and the vitamin. Furthermore, vitamin D deficiency may also result in muscle weakness, especially, if you experience a change in strength of muscles that is unexplained.

8. Infertility

Unexplained infertility is also a symptom of deficiency of this vitamin.

Treatment

Ideal intake of vitamin D varies according to different factors including age, metabolic health and activity level. You should discuss with your physician about your goals of intake of Vitamin D.

It is good to maintain a log of signs and symptoms at the start of treatment. In this way you can track your progress and assess in between whether it is required to up your intake of vitamin D.

Three strategies exist to increase the levels of vitamin D:

• Ingest a supplement of Vitamin D: You can easily get them over the counter. Your physician can also prescribe them. For majority of the adults, the RDA (recommended dietary allowance) is 600 IU (international units). For adults above age 70 years, it is 800 IU. For kids below the age of 12 years the RDA is 400 IU.
• Consume food sources that have vitamin D: Fatty fish including salmon, mackerel and tuna and fish liver oils are rich in the vitamin. Cheese, egg yolks and beef liver have small amounts. It is also present in fortified dairy and cereals.
• Increase your exposure to sunlight: The risks of exposure to sun may be higher in comparison to risks of vitamin D deficiency for individuals prone to sunburn, with skin cancer history or with pale skin. You should consult your physician before increasing your time in sunlight.