For humans, self-production of B12 through the intestinal bacteria is theoretically possible, but rarely achieved for health reasons, which is why humans today depend on a dietary intake of B12 in almost all cases
Twice daily 1 Capsule BPC Probiotic BPC | Live Probiotic* Active Ingredients: Akkermansia (Live Akkermansia muciniphila), BPC 250mcg (as Pentadeca Short Chain Amino Acids), Sunfiber Prebiotic (Galactomannan Fiber) Other Ingredients: Vegetable Capsule (Hypromellose, Gellan Gum), Microcrystalline Cellulose, Salcaprozate Sodium, Magnesium Stearate Take 1-2 capsules two times daily with water or as directed by your healthcare practitioner
National Library of Medicine: Vitamin B12 Deficiency Obesity Science and Practice: Inositol supplementation and body mass index: A systematic review and meta-analysis of randomized clinical trials Annual Review of Nutrition: Choline and Human Nutrition
B vitamin therapy is beneficial in patients with good renal function, but harmful in patients with significantly impaired renal function