Magnesium glycinate may help muscle tightness, but if it is going to be beneficial, improvement is usually noticed within 2–4 weeks of regular use. It is generally safe to continue for a few months in healthy adults when taken at recommended doses.
Since your
vitamin B12,
vitamin D, and serum magnesium levels are normal, persistent neck and shoulder stiffness may also be related to posture, muscle strain, stress, or other musculoskeletal causes.
Next Steps
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