Vitamin B12 underpins many important processes in the body, such as DNA synthesis, energy production, and central nervous system function. Falling short of B12 can therefore cause a cascade of problems. It’s important to respond to the warning signs as a prolonged B12 deficiency can lead to permanent problems.
Hampering early detection is the “non-specific” nature of symptoms.
According to an article published in the BMJ, “non-specific symptoms such as fatigue are the “earliest manifestations”.
The BMJ article states that autonomic dysfunction, it seems, “is a common manifestation of functional vitamin B12 deficiency and seems to occur early in the course of disease process”.
Autonomic dysfunction, also known as autonomic neuropathy, occurs when the nerves that control involuntary bodily functions are damaged.
READ MORE: B12 deficiency: BMJ warns low B12 can cause ‘permanent neurologic damage’ – five signs
“These conditions can often be diagnosed based on your symptoms and the results of a blood test.”
What causes low B12?
Vitamin B12 is only naturally found in animal products such as meat and dairy, so vegans and vegetarians are at risk of low intakes, explains Holland and Barrett.
According to the health body, older people and others who don’t produce enough stomach acid to absorb B12 properly, may also be at risk of deficiency.
The most common cause in the UK is pernicious anaemia – an autoimmune condition that affects your stomach.
B12 can also be found in the following foods:
- Meat
- Salmon and cod
- Milk and other dairy products
- Eggs.
According to the NHS, people who find it difficult to get enough vitamin B12 in their diets, such as those following a vegan diet, may need vitamin B12 tablets for life.
“Although it’s less common, people with vitamin B12 deficiency caused by a prolonged poor diet may be advised to stop taking the tablets once their vitamin B12 levels have returned to normal and their diet has improved,” explains the health body.
It adds: “Check the nutrition labels while food shopping to see how much vitamin B12 different foods contain.”