A Mental Sign of Vitamin B12 Deficiency

Vitamin B12 is relatively high in foods including fish, poultry, eggs and low-fat milk.

Vitamin B12 is relatively high in foods including fish, poultry, eggs and low-fat milk.

Difficulties with thinking and memory skills might be a sign of a lack of vitamin B12, research suggests.

People with a vitamin B12 deficiency find it hard to learn words and names and solve puzzles, a study finds.

In addition, vitamin B12 deficiency is linked to problems maintaining attention.

A deficiency in vitamin B12 has also been linked to brain shrinkage.

One study of 1,459 older people measured their folate and vitamin B12 levels, as well as giving them cognitive tests.

The results were explained by Dr Martha Savaria Morris, the study’s first author:

“We found a strong relationship between high folate status and good cognitive function among people 60 and older who also had adequate levels of vitamin B12.”

Some good sources of folates include:

  • fruits,
  • vegetables,
  • chickpeas,
  • lentils,
  • liver,
  • and whole-grains.

Vitamin B12 is relatively high in foods including fish, poultry, eggs and low-fat milk.

Dr Morris said:

“People with normal vitamin B12 status performed better if their serum folate was high.

But for people with low vitamin B12 status, high serum folate was associated with poor performance on the cognitive test.”

In contrast, low vitamin B12 was problematic:

“For seniors, low vitamin B12 status and high serum folate was the worst combination.

Specifically, anemia and cognitive impairment were observed nearly five times as often for people with this combination than among people with normal vitamin B12 and normal folate.”

People who may have difficulty getting enough vitamin B12 include vegetarians and those with some digestive disorders, such as Crohn’s disease.

Dr Morris concluded:

“Our findings support the often-expressed idea that many seniors would benefit from more folate, but the research shows that we must look at the effects this would have on seniors with age-related vitamin B12 deficiency, who may be more numerous than once realized.”

The study was published in the American Journal of Clinical Nutrition (Morris et al., 2007).

Author: Jeremy Dean

Psychologist, Jeremy Dean, PhD is the founder and author of PsyBlog. He holds a doctorate in psychology from University College London and two other advanced degrees in psychology. He has been writing about scientific research on PsyBlog since 2004. He is also the author of the book "Making Habits, Breaking Habits" (Da Capo, 2013) and several ebooks.

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