Hair thinning or excessive hair loss may be another clue. Although hair loss can have many causes, research suggests severe vitamin D deficiency may affect hair follicle health in some individuals. Slow wound healing is another possible symptom because vitamin D contributes to skin repair and inflammation control.
Some people also experience excessive sweating, particularly around the head. This unusual symptom has long been associated with low vitamin D levels in both adults and children. Muscle cramps, tingling sensations, and poor balance may also occur as deficiency worsens.