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Yes, and there's a good biological rationale for doing so
Conditions like celiac disease, inflammatory bowel disease, gastric surgeries, or chronic use of certain medications can reduce absorption from food and pills. If you have ongoing digestive issues, your provider may recommend a combination of gutsupporting strategiessuch as probiotics, a balanced diet, or targeted therapiesalong with B12, often using injections to bypass the digestive tract altogether
Dietary B group vitamin intake and the bladder cancer risk: A pooled analysis of prospective cohort studies
In fact, low B12 levels can cause discolouration of nails, brittle hair, dry lips and mouth and even hyperpigmentation