Vitamin B12 is absorbed from food in the terminal ileum (the last part of the small intestine)
B Vitamins: Support energy metabolism, provide stress support, improve cognitive function and mood
Typical applications include: Obesity and Body-Weight Regulation Models : Studying how chronic AOD 9604 exposure affects body weight, fat, and energy expenditure in obese rodents, often using indirect calorimetry and body composition analyses
If you bought it from a UK supplier then it's much more likely that your they have had them stored at room temperature for days/weeks/months
For those who eat meat and dairy and do not have an underlying issue preventing B12 absorption, this should not be a problem
It can mean more binding protein in circulation, vitamin released from injured cells, reduced clearance by the liver or kidneys, recent intake, or analytical interference, where the measured value does not accurately reflect the true B12 status