Last reviewed: April 2026 Next scheduled review: October 2026 (FY2027 update) Ready to turn this knowledge into a credential
One study found lower vitamin B 12 levels in the cerebrospinal fluid of patients with Alzheimer's disease than in patients with other types of dementia, though blood levels of vitamin B 12 did not differ (65)
Other symptoms of B12 deficiency include pale skin, loss of appetite, heart palpitations, unexplained weight loss, depression, poor memory, confusion, and soreness of the mouth or tongue
Vitamin B12 injections are generally considered to be safe and have no major side effects
Talk to a qualified clinician before any use
B is crucial for the metabolism of fats, drugs, and steroids and for the activation of other vitamins (it helps convert vitamin B to its active form and aids the conversion of tryptophan to niacin)