Vegans are at risk for deficiency of which vitamin, leading to tingling and numbness?

• A. Vitamin C
• B. Vitamin D
• C. Vitamin A
• D. Vitamin B12

Answer: (D)

Tingling and numbness point to nerve dysfunction caused by a deficiency of vitamin B12, which is essential for maintaining the myelin sheath that insulates nerves. Vegans are at risk because this vitamin is abundant in animal products and is often lacking in unfortified plant foods. Without sufficient B12, myelin deteriorates, leading to neuropathic symptoms like paresthesias—tingling and numbness in the hands and feet—and, if not addressed, balance problems and impaired sensation. Neurologic signs can appear before anemia, so these sensory changes in someone who doesn’t consume animal products strongly suggest B12 deficiency. Other vitamin deficiencies don’t typically present with this peripheral neuropathy as a primary feature.