2026 Study Links Low Vitamin B12 to Mitochondrial Damage, Fatigue Before Anemia
Updated
Updated · SciTechDaily · Jun 20
2026 Study Links Low Vitamin B12 to Mitochondrial Damage, Fatigue Before Anemia
3 articles · Updated · SciTechDaily · Jun 20
Summary
A 2026 study found low vitamin B12 disrupted mitochondrial DNA and cut energy production in skeletal muscle cell models, offering a mechanism for fatigue that can appear before clear anemia.
A related mouse study in aged females showed B12 supplementation improved mitochondrial number, structure and other markers of muscle health, strengthening the link between B12 status and cellular energy.
Doctors have long tied B12 deficiency fatigue to anemia, but the new work suggests exhaustion may also stem directly from impaired mitochondrial function because one of only 2 B12-dependent enzymes works inside mitochondria.
B12 deficiency remains common in older adults, vegans, vegetarians and people with poor absorption from autoimmune gastritis, weight-loss surgery or some diabetes and acid-reflux drugs.
The findings do not support B12 shots as an energy booster for people with normal levels; testing and treatment are most useful when deficiency is confirmed.