Clinically, however, the evidence is mixed : Vitamin B12 has a well-established role in energy metabolism, especially in deficient individuals
,
Neurological symptoms are particularly characteristic and may include: Paraesthesia (pins and needles) in the hands and feet Numbness or altered sensation in the extremities Difficulty with balance and coordination, often due to spinal cord involvement (subacute combined degeneration) Memory problems and cognitive impairment Mood changes, including depression and irritability Visual disturbances (rare and usually in advanced deficiency) Haematological manifestations commonly present as symptoms of anaemia: Persistent fatigue and weakness Breathlessness, particularly on exertion Palpitations or rapid heartbeat Pale or jaundiced (yellowish) skin Glossitis (sore, red tongue) Mouth ulcers Additional signs may include: Unexplained weight loss Diarrhoea or constipation Loss of appetite Muscle weakness The severity and combination of symptoms vary considerably between individuals

They should be kept at room temperature, away from moisture, heat, and especially light, as light can make the vitamin unstable
Importantly, 5-amino-1MQ is highly selective
Crohn's Disease and Celiac Disease: Both of these inflammatory conditions can damage the terminal ileumthe very last section of the small intestine where B12 absorption happens