Vitamin B12 deficiency threatens Alzheimer’s disease

Low levels of vitamin B12 in the blood of older adults can negatively affect their brain size and intelligence, new research suggests.

It has previously been found that people with high blood levels of vitamin B12 have lower levels of an amino acid called homocysteine. According to some reports, it is associated with an increased risk of Alzheimer’s disease, memory loss and stroke.

The new study involved 121 people over 65 from Chicago. The scientists measured their blood levels of vitamin B12 and its metabolites (metabolic intermediates), which indicate B12 deficiency. Participants completed tests that tested memory and other cognitive abilities.

Approximately 4.5 years later, the participants took these tests again. They underwent an MRI in order to determine the volume of the brain and to identify signs of impaired functioning. It was found that in the presence of a high level of four markers of vitamin B12 deficiency out of five possible brain volume was less, and test scores ? below.

The test scores ranged from -2.18 to 1.42, with a mean score of 0.23. For each increase in homocysteine ​​by 1 micromoles per liter, the test scores decreased by 0.03 points. Remarkably, better test results and larger brain volume were not associated with the level of vitamin B12, but with the concentration of its markers.

According to Health Canada, adults should get 2.4 micrograms of vitamin B12 per day. As co-author of the study, Dr. Martha Clare Morris of the Rush University Medical Center, points out, it is difficult to detect B12 deficiency in older people based on blood levels alone. It is better to measure the amount of homocysteine.

In general, there is still too little evidence that all people of retirement age should take drugs containing B12, says Dr. Morris. And in older people with signs of intellectual disability, vitamin supplements reduce brain mass loss and slow mental regression, according to last year’s UK study.

Canadian scientists plan to continue developing this topic next year. “We want to know if mental illness can be prevented in the elderly by offering them a B-rich diet or supplementation,” explains Dr. Morris.

But Eugene Boggs, the doctor prescribed B12 injections 4 years ago. The woman is now 89 and works full-time at a nursing home in Lower Toronto. Eugene gets one shot a month. “After the injection, I feel better both physically and mentally. I think more clearly than at 21,” she says.

Vitamin B12 is found in animal products and foods like fortified cereals. There is a lot of it in offal, for example, in the liver, and in oysters. Smaller amounts of B12 are found in meat, poultry, fish, dairy products, and eggs. Older adults find it difficult to absorb B12 from food due to changes in digestion, as do patients with celiac disease, Crohn’s disease, and diabetes.