PLoS ONE 8 , e74083 (2013)
Who should avoid B12 supplementation
My level was 210 which is not considered low at my gp
You should contact your GP or NHS 111 if you experience: Persistent diarrhoea lasting more than 7 days in otherwise healthy adults Blood or mucus in stools , which may indicate inflammatory bowel disease or infection Severe abdominal pain or cramping that is worsening or different from previous digestive symptoms Unexplained weight loss alongside bowel changes Signs of allergic reaction , including rash, itching, swelling, or difficulty breathing (call 999 or go to A&E for severe reactions) Neurological symptoms such as numbness, tingling, balance problems, or memory difficulties, which may indicate B12 deficiency is not being adequately treated Seek help sooner if you have red flag symptoms, are pregnant, immunosuppressed, elderly, or have significant underlying health conditions
If you experience progressive numbness, meaningful weakness, frequent falls, or new bowel or bladder issues, seek medical evaluation promptly
Methylcobalamin appears in many nutraceutical products