According to the NHS, people with the problem could notice a change in their memory skills
Amber O’Connor Money and Lifestyle reporter U35s
15:43, 07 Feb 2026
People might not be aware of their vitamin deficiency (stock photo)(Image: Getty)
People suffering from unexplained memory issues could be dealing with a vitamin deficiency, the NHS has warned. The health service provides detailed guidance on nutritious eating through its website, stressing how crucial a well-balanced diet is for maintaining both mental and physical health.
The NHS also shares warnings about several possible vitamin deficiencies and the symptoms to watch for. According to the NHS, problems with your memory, understanding, or judgement can sometimes be caused by a vitamin B12 or folate deficiency.
The NHS explains: “Vitamin B12 or B9 (commonly called folate) deficiency anaemia occurs when a lack of vitamin B12 or folate causes the body to produce abnormally large red blood cells that cannot function properly. Red blood cells carry oxygen around the body using a substance called haemoglobin.
“Anaemia is the general term for having either fewer red blood cells than normal or having an abnormally low amount of haemoglobin in each red blood cell.”
The NHS continues: “Vitamin B12 and folate perform several important functions in the body, including keeping the nervous system healthy. A deficiency in either of these vitamins can cause a wide range of problems, including:
extreme tirednessa lack of energypins and needlesa sore and red tonguemouth ulcersmuscle weaknessproblems with your visionpsychological problems, which can range from mild depression or anxiety to confusion and dementiaproblems with memory, understanding and judgement
Meat, eggs, and milk are good sources of vitamin B12 (stock photo)(Image: Getty)
“Some of these problems can also happen if you have a deficiency in vitamin B12 or folate but do not have anaemia.”
Always see a GP if you think you may have a vitamin B12 or folate deficiency or have any other health concerns. These conditions are usually diagnosed with a blood test, and the NHS says they should be treated as soon as possible.
While your doctor will explain the best course of treatment for you, these conditions are often treated using injections or tablets. Some people might be able to help treat the condition by adjusting their diet. The treatment required will depend on the underlying cause of the problem.
Vitamin B12 or folate deficiency can be caused by certain medicines, pernicious anaemia, or a lack of these vitamins in your diet. The most common cause of vitamin B12 deficiency in the UK is pernicious anaemia, according to the NHS.
Vitamin B12 deficiency can cause people to feel tired (stock photo)(Image: Getty)
The NHS says that diets that include meat, fish, and dairy products normally provide enough vitamin B12, but people who don’t eat these foods regularly can become deficient. Good sources of vitamin B12 include meat, fish, eggs, and dairy products, while some foods are also specially fortified. Good sources of folate include green vegetables, such as broccoli and peas.
However, people who take supplements should be aware that taking too much vitamin B12 could also be harmful. The NHS says taking 2mg or less of vitamin B12 per day in supplements is unlikely to cause any harm.
