Intriguing Discovery: Risk of Dementia Higher For Old People With High, Low Levels of Magnesium in Blood

Too Much, Too Little Magnesium Not Good For Old People

A new study revealed a strong association of developing dementia for people with both high and low levels of magnesium in their blood.

The study conducted by Dutch researchers involved 9,569 people with an average age of 65. The blood of all respondents was tested for magnesium levels. Around 823 people were diagnosed with dementia in a span of 10 years. But what intrigued the researchers most was the fact that those in a group with higher and low levels of magnesium developed dementia compared with those elderly with normal magnesium range.

These key findings were confirmed by head author, Brenda C.T. Kieboom, MD, MSc, from Erasmus University Medical Center in Rotterdam, the Netherlands.

Kieboom said, “These results need to be confirmed with additional studies, but the results are intriguing.”

This study was published in an online issue of Neurology®, the medical journal of the American Academy of Neurology.

An elderly woman with dementia.
An elderly woman with dementia.

The Study and Results

To look for factors that put old people at risk of dementia, the researchers invited around 10,000 people to be respondents of the study. Levels of magnesium were measured among the participants through blood testing.

The researchers divided participants into five groups based on their magnesium levels. Both those with the highest and the lowest levels of magnesium showed increased risk of dementia, compared to those in the middle group.

In details, respondents with low and high levels of magnesium, 30% of them developed dementia through the span of 10 years. This means out of the 1,771 people in the low magnesium group, 160 people developed dementia, which is a rate of 10.2 per 1,000 person-years. For the high magnesium group, 179 of the 1,748 people developed dementia, for a rate of 11.4 per 1,000 person-years.

The results were the same after researchers adjusted for other factors that could affect the risk of dementia and magnesium levels, such as body mass index, smoking status, alcohol use and kidney function.


Kieboom said that if the results are confirmed, blood tests to measure magnesium levels could be used to screen for people at risk of dementia. She emphasized that the study does not prove that high or low levels of magnesium cause dementia; it only shows an association.

Kieboom stressed that the study has limitations. One is that magnesium levels were measured only once, so they could have changed, and that magnesium levels in the blood do not always represent the total level of magnesium in the body.

What is Dementia?

Dementia is caused when the brain is damaged by diseases, such as Alzheimer’s disease or a series of strokes. Alzheimer’s disease is the most common cause of dementia, but not the only one.

It mainly affects people over the age of 65 (one in 14 people in this age group have dementia), and the likelihood of developing dementia increases significantly with age.

Mina Fabulous follows the news, especially what is going on in the US State Department. Mina turns State Department waffle into plain English. Mina Fabulous is the pen name of Carmen Avalino, the NewsBlaze production editor. When she isn’t preparing stories for NewsBlaze writers, she writes stories, but to separate her editing and writing identities, she uses the name given by her family and friends.