From the Guidelines
Vitamin D deficiency and excess both cause distinct side effects, with deficiency symptoms including fatigue, bone pain, and muscle weakness, and excess symptoms including nausea, vomiting, and kidney problems, as noted in studies such as 1 and 1.
Symptoms of Deficiency and Excess
The symptoms of vitamin D deficiency and excess are distinct and can have serious health implications if left untreated.
- Deficiency symptoms include:
- Fatigue
- Bone pain
- Muscle weakness
- Mood changes like depression
- Impaired wound healing
- Bone loss
- Increased susceptibility to infections
- Excess symptoms include:
- Nausea
- Vomiting
- Weakness
- Frequent urination
- Kidney problems
- Bone pain
- Calcium buildup in blood vessels
Causes and Risks
Vitamin D is crucial for calcium absorption, bone health, immune function, and cell growth regulation.
- Deficiency can occur due to low vitamin D intake, decreased vitamin D absorption, and little or no sun exposure, as discussed in 1 and 1.
- Excess, or hypervitaminosis D, typically results from supplement overuse rather than sun exposure or diet, leading to hypercalcemia, as noted in 1 and 1.
Recommended Intake and Blood Levels
The recommended daily intake for most adults is 600-800 IU, with blood levels ideally between 20-50 ng/mL, as suggested in 1 and 1.
- If you suspect either condition, consult a healthcare provider for proper testing and treatment, as both deficiency and toxicity can cause serious health problems if left untreated, as emphasized in 1 and 1.
From the Research
Vitamin D Deficiency Symptoms
- A mild lack of vitamin D may not cause symptoms but can cause tiredness and general aches and pains 2
- A more severe lack can cause serious problems such as rickets (in children) and osteomalacia in adults) 2
- Common manifestations of vitamin D deficiency are symmetric low back pain, proximal muscle weakness, muscle aches, and throbbing bone pain elicited with pressure over the sternum or tibia 3
- Low vitamin D status is associated with an increased risk of falls and proximal weakness 4
Vitamin D Toxicity (Hypervitaminosis D) Symptoms
- Hypercalcaemia is a common diagnosis resulting from hypervitaminosis D-induced hypercalcaemia 5
- The classic manifestation of vitamin D toxicity is hypercalcemia, which may be refractory to conventional therapy 6
- Susceptibility to vitamin D toxicity shows a significant inter-individual variability that may in part be explained by genetic predispositions (i.e., CYP24A1 polymorphism) 6
Comparison of Vitamin D Deficiency and Toxicity
- Vitamin D deficiency is associated with cardiovascular disease, the metabolic syndrome, type 2 diabetes mellitus, cancer as well as with increased mortality, while vitamin D toxicity is associated with hypercalcemia and refractory conventional therapy 2, 6
- Treatment for vitamin D deficiency includes oral ergocalciferol (vitamin D2) at 50,000 IU per week for eight weeks, while treatment for vitamin D toxicity may include systemic corticosteroids, inhibitors of 1α-hydroxylase, and inducers of CYP3A4 3, 6