There are several cases for vitamin B12 deficiency, but the most common cause is malabsorption. Older adults with atrophic gastritis, people with stomach and small intestine disorders (coeliacs and Crohn's disease) and people who had gastrointestinal surgery may be unable to absorb enough B12 from food. Weight loss surgery may remove some parts of the stomach, losing the cells that secrete HCL and intrinsic factor. Surgical removal of ileum leads to inability to absorb vitamin B12.
Vegans are also at risk of B12 deficiency, as plant based meals lack B12 vitamins, and strict vegans are more at risk than lacto-ovo-vegetarians, as milk, dairy and eggs have some B12. Pregnant and lactating women, and their infants are at risk if they are strict vegans, as B12 crosses placenta and goes into breast milk, so they need to take supplements. Undetected B12 deficiency in children leads to severe and permanent neurological damage.
And to close with a good news, there is no toxic or adverse effect with vitamin B12 from food or supplements.
The next post I will talk about the remaining B vitamins (thiamine, riboflavin, niacin, pantothenic acid, B6 and biotin).
P.S. If you are Romanian, you can also publish your post link in the Publish0x Romanian Community Facebook group for others to read it.
...get the higher rewards for your investments using Blockfi for $50 bonus in BTC and Celsius.network, use Celsius referral 1235256530 for $20 bonus. Crypto.com is also a good choice at the moment, with the native coin CRO, being cheap to buy.
Disclaimer: This text is also re-published on my personal blogs, such as this one.