If you don’t get enough vitamin D, it can take weeks, months, or even longer to develop symptoms. The effects of vitamin D deficiency vary with age and impact bone development, bone strength, the immune system, muscle health, energy levels, and other aspects of health.
1. Fatigue
Fatigue is one of the most nonspecific symptoms of vitamin D deficiency, and there are several different ways that a lack of vitamin D can lead to fatigue.
It has been shown that vitamin D deficiency can interfere with sleep, and a lack of adequate sleep can make you tired during the day. Additionally, the inflammation and neurotransmitter disruption associated with vitamin D deficiency can impact your energy levels, contributing to fatigue.
2. Muscle and Joint Pain
A low level of vitamin D is associated with inflammation. Inflammation occurs when the body releases chemicals that intended to trigger an immune response to fight an invader or help heal damaged tissue.
Inflammation causes many different symptoms, and vitamin D-associated inflammation can cause generalized muscle aches and joint pain, as well as arthritis.
3. Frequent Infections
Vitamin D helps regulate your immune system, and an immune deficiency can make you susceptible to frequent or severe infections.
Chronic obstructive pulmonary disease (COPD), a lung disease that causes coughing, wheezing, shortness of breath, and low overall energy, has several different contributing factors, including smoking and lung inflammation. This lung condition can increase your susceptibility to infections and is often associated with vitamin D deficiency.
4. Depressed Mood
There’s an association between low vitamin D and depression. Your mood is influenced by the balance of neurotransmitters (chemicals that carry messages between nerves) in your body. Some research suggests that a lack of vitamin D can lead to an imbalance of the neurotransmitters that help regulate your mood, leading to depression.
Additionally, seasonal effective disorder (SAD), a condition in which people become very depressed as a result of low sun exposure, is associated with a lack of vitamin D. The body produces vitamin D when skin is exposed to sunlight.
5. Rickets in Children
Bone formation during childhood relies on adequate vitamin D. Children who are deficient in vitamin D during the years of rapid growth can develop a condition called rickets, characterized by inadequate bone formation, bone deformities, bone fragility, brittle teeth, and muscle aches.
6. Bone Fractures
Vitamin D is necessary for bone health, including during adulthood. Adults who are low in vitamin D develop osteopenia and osteoporosis, which are conditions of low bone density.
Osteoporosis is more severe than osteopenia and can develop if osteopenia is not treated. It often has no symptoms, but increases the risk of fractures, even from minor bumps.
7. Multiple Sclerosis
Multiple sclerosis is a chronic neurological condition caused by inflammatory processes that affect brain and spinal cord function. There’s a strong association between vitamin D deficiency and multiple sclerosis, as well as a link between low sun exposure and an increased risk of developing multiple sclerosis.
8. Heart Disease
A vitamin D deficiency affects your heart in several ways. Inflammation caused by vitamin D deficiency can increase the risk of heart disease. Vitamin D also affects blood vessel health and heart muscle function, which leads to an association between vitamin D deficiency and an increased risk of heart attack.
9. Type 2 Diabetes
Type 2 diabetes, metabolic syndrome, insulin resistance, and obesity are all related to each other. Vitamin D deficiency can increase your risk of these conditions, and inflammation may play a role in this link.
Vitamin D and Inflammatory Bowel Disease
The link between vitamin D and inflammatory bowel disease is bidirectional. Vitamin D deficiency is linked to inflammation, which can increase the risk of inflammatory bowel disease. Additionally, inflammatory bowel disease interferes with the absorption of nutrients from your food—including vitamin D. So, vitamin D deficiency and inflammatory bowel disease exacerbate each other.
Key Takeaways
Vitamin D is involved in numerous physiological processes within the body.A deficiency of vitamin D can cause a variety of nonspecific signs and symptoms, such as fatigue and muscle or joint pain, and they may not be noticeable until weeks, months, or longer.Some conditions associated with vitamin D deficiency include rickets, osteopenia, heart disease, multiple sclerosis, and depression.
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