Vitamin B12 Deficiency: Signs, Testing, and Treatment
Vitamin B12 deficiency is common, often missed on a standard blood panel, and straightforward to treat once it’s actually caught. Fatigue, brain fog, numbness in the hands and feet, and mood changes are the most common signs, and testing usually starts with a serum B12 level, though methylmalonic acid or homocysteine testing catches deficiencies a standard test misses. GLP-1 medications and metformin, both common in a medical weight loss program, raise deficiency risk in ways most B12 guides don’t mention. Treatment is B12 injections or high-dose oral supplementation, chosen based on how low levels are and how severe the symptoms have gotten.
