27/07/2025
Sally Packolok keynoting at the UK B12 Deficiency campaign conference, alongside Umahro Cadogan, an expert in nutrition, functional medicine, and others. Organised by Tracey Witty and held at Loughborough University, the conference was aimed at both health professionals and patients.
B12.
Vitamin B12 or cobalamin is essential for the development and maintenance of a healthy brain and nervous system. It’s necessary for red blood cell production and for DNA synthesis, being key for methylation and the metabolism of folate, homocysteine, and methylmalonyl coenzyme A. B12 is only found in foods of animal origin, i.e. meat, fish, shellfish, poultry, dairy products, and eggs. Vegans and vegetarians require additional B12 supplements to avoid deficiency symptoms. The absorption of B12 is a complex process involving numerous organs, co factors and biochemical steps. In brief, vitamin B12 binding protein is produced by the salivary glands and stomach parietal cells. Hydrochloric acid and pepsin begin the breakdown in the stomach with pancreatic enzymes and intrinsic factor, produced by the parietal cells, then acting on the released B12 in the small intestine. Receptors in the distal ileum (end of the small intestine) are also involved in absorption. Once in the blood, specific proteins (transcobalamin 2) shunt the active B12 to cells and organs. Problems at any of these steps can lead to malabsorption and subsequent deficiency. Yet deficiency of B12 is still poorly recognised by mainstream medicine.
Avoiding B12 deficiency
The US Centers for Disease Control (CDC) tell us ‘Research studies and clinical laboratories have tended to dichotomize low values [serum B12 levels] at 200 picograms per milliliter (pg/mL)”). They warn that “Accepted lower limits of serum B12 levels in adults range between 170 and 250 pg/ml; however, higher levels (but less than 350 pg/ml) have been recorded in 15% of ostensibly healthy elderly patients with other findings suggestive of a deficiency state… the true lower limits of normal serum B12 would therefore appear to be somewhat poorly defined”. Sally Pacholok stressed that on both sides of the Atlantic mainstream clinicians are using too low reference ranges and missing many deficiency cases.
In the UK, B12 serum levels are measured in nanograms per litre (ng/L) with reference ranges starting as low as
