TYPE 2 DIABETES

The Effects of High Blood Sugar

By Richard Asa @RickAsa
 | 
March 02, 2015
Blue light shining from brain of mixed race man --- Image by © John Lund/Blend Images/Corbis

One of the side effects of high blood sugar, recent research shows, is memory loss. 

As more research is done on the health effects of high blood sugar, the more evidence emerges that there’s nothing good about unregulated control. Some of the latest evidence suggests that people who control their blood sugar levels earlier in life will have a healthier brain later in life.

Researchers who evaluated the brain health of thousands of people at three visits between 1990 and 2013 found that those with uncontrolled both type 1 and type 2 diabetes at the first visit had a steep cognitive decline over the years compared to those who had their condition under control.

Participants were about 57 years old when they entered the study. Those with diabetes had a greater cognitive decline in general during the study, compared to people without diabetes. People with pre-diabetes had an even greater decline than people without it.

The upside of the results, the researchers say, is that diabetics have time to prevent the mental decline with healthy changes in their diet and exercise when they are in their 50s. The earlier the prevention starts, they add, the greater the benefit may be.

“Our blood sugar levels now and in the future are going to be integral as it pertains to many health-related conditions,” says certified nutritionist and fitness expert Robert Ferguson, MS, CN, a member of the presidential task force on obesity for the National Medical Association. “At first glance, this research demonstrates how the fluctuations of blood sugar levels (eating too many carbs at one time and not eating enough in a timely manner) can prove quite damaging.”

“Learning to eat foods in the right amounts (portions) and in combinations with others foods is going to prove key for lowering the risk of losing brain power. This also pertains to lowering the risk of cognitive declines, dementia, and pre-diabetics becoming type 2 diabetics.” 

A researcher who studies the impact of obesity and diabetes on the brain, Lawrence Reagan, told Reuters that many factors linked to diabetes may lead to cognitive decline, even dementia.

“I think their data are very compelling,” said Reagan, a researcher at the University of South Carolina. “It provides further support for a concept that should be pretty easy for people to understand.”

“One of the medical signs of diabetes is magnesium deficiency, so I equate the diminishing brain power (from) diabetes and high blood sugar with magnesium deficiency," adds Carolyn Dean, MD, ND, an advisory board member for the non-profit National Magnesium Association.

"In one study, researchers found that elevated brain magnesium was able to induce the production of BDNF, your brain’s rejuvenation compound. This led to an increase in synaptic plasticity, enabling the learned fear response to actually change.”

This may be applicable to diabetes because poor control over blood sugar can decrease neuroplasticity, which reduces cognitive function and makes the brain seem older. If you have diabetes, you should talk to your doctor or nutritionist about the practicality of magnesium supplements.

Neurologist David Perlmutter, MD, author of the best-selling consumer book “Grain Brain,” has long believed that carbohydrates (including sugar) are causing mental decline.

The book reviews scientific literature that he says demonstrates a significant increased risk for developing Alzheimer’s disease or dementia in people with type 2 diabetes.

Perlmutter also says that a recent report in the journal Clinical Interventions in Aging further establishes diabetes as a risk factor for cognitive impairment. “The researchers describe a variety of factors relating type II diabetes to brain dysfunction including impaired neurogenesis which is the process by which we are able to grow new brain cells, specifically in the brain’s memory center, hippocampus,” he writes. “This is compromised in diabetes.”

In practical terms, this amounts to a diet very low in sugar and carbohydrates and high in fiber from “above ground” vegetables, plus a lifestyle high in physical activity, Perlmutter says.

Updated:  

February 21, 2020

Reviewed By:  

Janet O’Dell, RN