Table of Contents
- Roles of Vitamin D
- Vitamin D Activities
- Vitamin D and Back Pain
- Vitamin D and Muscle Pain
- Treating Low Vitamin D Levels
The body obtains vitamin D in three ways. One source is food. Second, the body produces vitamin D naturally through exposure to the sun’s ultraviolet rays. Supplements are a third source. Vitamin D is key to good health in many ways, including supporting the growth of strong bones and normal muscle contractions. For these reasons, researchers are discovering links between a vitamin D deficiency and chronic low back pain and muscle pain.
Many Roles of Vitamin D in the Body
Vitamin D has more roles in the body than many people realize.
- As a fat-soluble vitamin, vitamin D helps with the absorption and retention of calcium in the gut, which is needed for healthy bone mineralization.
- In addition to supporting bone mineralization, vitamin D helps maintain serum calcium and phosphate levels, preventing involuntary muscle contractions that can lead to painful spasms and cramps.
- At the right concentration, Vitamin D supports bone remodeling and growth by stimulating the specialized activities of osteoblasts (growth) and osteoclasts (resorption). The combined cell activity helps maintain bone homeostasis.
- Vitamin D assists with reducing inflammation and supporting immune function.
- Vitamin D has a role in neuromuscular functioning. Neuromuscular refers to the connection between muscles and nerves.
- Various genes encoding proteins involved in cell production, differentiation, and apoptosis (cell death) are modulated by vitamin D.
Low vitamin D refers to a mild insufficiency of the vitamin in the blood. A vitamin D deficiency refers to a significant lack of this essential nutrient. There are standard blood tests that doctors use to assess a person’s vitamin D levels.
Vitamin D Activities
A vitamin D deficiency can contribute to the development of chronic pain. Various research projects have found that its role in managing cellular activities enables it to act as a natural neuroactive steroid. This means that vitamin D interacts with brain receptors located on neuronal membranes (the outer boundary of neurons). Low vitamin D disrupts cellular activity, preventing neuroactive steroids from exerting their natural analgesic, anti-inflammatory, and neuropathic pain-reducing effects.
Low vitamin D levels may impair the production and activity of neurotrophins, proteins crucial for normal nervous system function. A vitamin deficiency can also influence prostaglandin activities. These hormones may trigger inflammation and pain, regulate muscle contraction in blood vessels and the uterus, and are involved in the blood clotting process.
A study examining various micronutrients, including vitamin D, found that lower vitamin D levels or a severe deficiency may be associated with chronic pain.
Vitamin D and Back Pain
The connection between low vitamin D and back pain is still being studied, but some facts are known. For example, persistently low vitamin D may lead to bone density loss. Over time, osteomalacia develops, a condition in which the bones soften and weaken. When vitamin D deficiency persists over a prolonged period, the process that maintains the balance between osteoclasts and osteoblasts is disrupted. The body tries to maintain serum calcium by basically robbing the bones of their calcium. Some of the symptoms include the following.
- Bone pain, commonly in the lower back and extremities
- Muscle weakness
- Muscle spasms
- Waddling gait
- Spinal or pelvic deformities
- Fractures that would not occur in healthy bones
Vitamin D is involved in inflammation and pain, but further research is needed to pinpoint precisely how. One study divided participants with low back pain into two groups. Half of the participants had low vitamin D levels, and half had normal levels. The group with a vitamin D deficiency experienced more severe pain. These studies are ongoing to better understand the complex link between vitamin D and pain.
Because bone pain and vitamin D deficiency are closely linked, any part of the back can experience discomfort due to bone and muscle weakness. For example, a vitamin D deficiency is linked to chronic neck and back pain and muscle spasms.
Vitamin D and Muscle Pain
People also experience muscle pain due to low vitamin D. Vitamin D promotes healthy muscle cell protein synthesis. When the process is disrupted, muscle pain and weakness may become symptoms of low vitamin D levels. The bone and muscle pain associated with low vitamin D is due to the interruption of natural processes that regulate calcium absorption, which is necessary for healthy bone metabolism and muscle function.
The muscle pain may also result from vitamin D deficiency, which can cause muscle hypersensitivity by affecting nerves. Muscle hypersensitivity is an increased response to certain stimuli, which can occur in conditions such as inflammatory disorders and fibromyalgia. It is expressed as pain or soreness.
There are many causes of chronic low back pain. If low back pain is due to a spinal condition, such as osteoarthritis or degenerative disc disease, the surrounding muscles are often involved.
Low vitamin D can increase muscle pain associated with low back medical conditions. The disruption of calcium and phosphorus absorption, along with an imbalance in pro- and anti-inflammatory cytokines, also contributes to muscle pain and weakness.
A severe, prolonged deficiency can even contribute to muscle atrophy and painful physical disability.
Treating Low Vitamin D Levels
There is a high prevalence of low vitamin D levels in patients with low back pain. Researchers are still studying whether low vitamin D levels actually cause low back pain, but to date, evidence suggests they contribute to the severity of the pain. They are also continuing to research the effect of vitamin D on back pain.
Vitamin D therapy for chronic musculoskeletal pain focuses on bringing levels to the appropriate range. A vitamin D treatment involves taking a vitamin D supplement. This may reduce inflammation and pain intensity for some patients.
A doctor-ordered blood test can determine a patient’s current vitamin D level. There are two types of supplements. Vitamin D2 is plant-based and requires a prescription. Vitamin D3 is animal-based and available as a supplement. It is essential to follow the doctor’s treatment plan because taking too much vitamin D is possible.
Sources
- https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/
- https://www.sciencedirect.com/science/article/abs/pii/S0039128X16300162
- https://pmc.ncbi.nlm.nih.gov/articles/PMC5466150/
- https://onlinelibrary.wiley.com/doi/10.1111/papr.70053
- https://www.ncbi.nlm.nih.gov/books/NBK551616/
- https://pmc.ncbi.nlm.nih.gov/articles/PMC6157211/#sec1-5
- https://pmc.ncbi.nlm.nih.gov/articles/PMC6730953/#sec12
- https://pubmed.ncbi.nlm.nih.gov/21957236/
- https://pmc.ncbi.nlm.nih.gov/articles/PMC7661179/