Low Levels of Vitamin B12 May Lead to Brain Shrinkage

Low Vitamin B12 Levels May Lead To

Brain Shrinkage and Cognitive Problems

Older people with low blood levels of vitamin B12 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 results of the study are published in the Sept. 27 issue of Neurology,
the medical journal of the American Academy of Neurology.

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.

On the cognitive tests, the scores ranged from -2.18 to 1.42, with an average of 0.23. For each increase of one micromole per liter of homocysteine, one of the markers of B12 deficiency, the cognitive scores decreased by 0.03 standardized units or points.

The level of vitamin B12 itself in the blood was not associated with cognitive problems or loss in brain volume. The researchers 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," they emphasized.

Reliable food sources of Vitamin B-12 are fish, meat, especially liver, milk, eggs and poultry. For those people whose diets do not provide adequate Vitamin B12, B vitamin supplements are recommended.

The study was supported by the National Institute on Aging.

Story Source: Rush University Medical Center

Journal Reference: Vitamin B12, cognition, and brain MRI measures: A cross-sectional examination. Neurology, 2011;

Rush University Medical Center (2011, September 27). Low vitamin B12 levels may lead to brain shrinkage, cognitive problems.