There is no single vitamin for joint and muscle pain, but certain deficiencies can worsen pain or recovery. Vitamin D is linked to muscle function and bone metabolism; deficiency may increase muscle aches and weakness. Vitamin B12 deficiency can contribute to neurological symptoms and some pain patterns. Magnesium relates to cramps and muscle relaxation; low levels can increase cramp tendency. The key principle is this: supplementation is meaningful when deficiency exists—without deficiency, don’t expect miracles. Pain causes can include overuse, inflammation, rheumatologic disease, or spine-related issues. Best practice is symptom review + labs + clinical evaluation, then targeted correction. Pair nutrition with lifestyle: protein, omega-3 intake, adequate sleep, and appropriate strength training can be as impactful as vitamins. Severe, night-waking pain or joint swelling/redness warrants medical assessment.