Vitamin B12 deficiency occurs when a lack of vitamin B12 or folate causes the body to produce abnormally large red blood cells that can’t function properly. The most common cause of a vitamin B deficiency is pernicious anaemia – where the immune system attacks healthy cells in person’s stomach, preventing their body from absorbing vitamin B12 from the food they eat. As people get older, their ability to absorb vitamin B12 tends to decrease – this can have serious health implications.
One study found that older people with low blood levels of vitamin B12 markers may be more likely to have lower brain volumes and have problems with their thinking skills, according to researchers at Rush University Medical Center.
The study involved 121 older residents of the South side of Chicago who are a part of the Chicago Health and Aging Project (CHAP), which is a large, ongoing prospective Rush a biracial cohort of 10,000 subjects over the age of 65.
The 121 participants had blood drawn to measure levels of vitamin B12 and B12-related markers that can indicate a B12 deficiency.
The same subjects took tests measuring their memory and other cognitive skills.
An average of four-and-a-half years later, MRI scans of the participants’ brains were taken to measure total brain volume and look for other signs of brain damage.
Having high levels of four of five markers for vitamin B12 deficiency was associated with having lower scores on the cognitive tests and smaller total brain volume.
“Our findings definitely deserve further examination,” said Christine C. Tangney, PhD, associate professor in the department of clinical nutrition at Rush University Medical Center, and lead author of the study.
“It’s too early to say whether increasing vitamin B12 levels in older people through diet or supplements could prevent these problems, but it is an interesting question to explore. Findings from a British trial with B vitamin supplementation are also supportive of these outcomes.”
Tangney noted that the level of vitamin B12 itself in the blood was not associated with cognitive problems or loss in brain volume.
She said that low vitamin B12 can be difficult to detect in older people when looking only at blood levels of the vitamin.
“Our findings lend support for the contention that poor vitamin B12 status is a potential risk factor for brain atrophy and may contribute to cognitive impairment,” said Tangney.
According to Harvard Health, Vitamin B12 deficiency can be slow to develop, causing symptoms to appear gradually and intensify over time.
It can also come on relatively quickly.
“Given the array of symptoms a vitamin B12 deficiency can cause, the condition can be overlooked or confused with something else,” explained the health site.
Vitamin B12 deficiency symptoms may include:
- Strange sensations, numbness, or tingling in the hands, legs, or feet
- Difficulty walking (staggering, balance problems)
- A swollen, inflamed tongue
- Difficulty thinking and reasoning (cognitive difficulties), or memory loss
According to the NHS, vitamin B12 deficiency is usually treated with injections of vitamin B12.
“Hydroxocobalamin is usually the recommended option as it stays in the body for longer,” explained the health body.