Insulin: Predictor for Alzheimer’s?

Fernanda Barros, Ivanhoe Health Correspondent

(Ivanhoe Newswire) — Could Alzheimer’s be a form of diabetes? Brain levels of insulin and its related cellular receptors fall during the early stages of Alzheimer’s, and as insulin levels continue to drop, the disease becomes more severe. Now, doctors are looking at memory problems like Alzheimer’s disease as a form of brain starvation, and one doctor says glucose metabolism can be the key to helping prevent this deadly disease.

Alzheimer’s disease is the most common form of dementia. Most often, it is diagnosed in people over 65, although the less-prevalent, early-onset Alzheimer’s can occur much earlier. In 2006, there were over 26 million sufferers worldwide. Alzheimer’s is predicted to affect 1 in 85 people globally by 2050. A recent study showed the inability of the brain to properly use glucose might be a key factor in the development of the disease.

“Type 1 and 2 diabetes are diabetes of the body, which means the body can’t handle sugar properly. Type 3 diabetes means the brain can’t handle sugar properly, “Larry McCleary, M.D., a neurosurgeon and author of Feed your Brain, Lose Your Belly, told Ivanhoe.

Dr. McCleary says diabetics have four-times the risk of developing Alzheimer’s, and those with prediabetes have triple the risk. Insulin and its related protein, insulin-related growth factor-I, lose the ability to bind to cell receptors. This creates a resistance to the insulin growth factors, causing the cells to malfunction and die.

“If you can’t handle your primary fuel source, then you can’t generate energy, and you lose function, and that’s pretty much what happens in Alzheimer’s disease,” Dr. McCleary explained. “Changes in brain glucose metabolism can occur in people who have no symptoms. Their brains are functioning normally in their 20’s and 30’s, but yet if you do scan, you can see subtle changes in glucose metabolism in the brain and not just anywhere in the brain. They are actually in the regions where Alzheimer’s disease develops when you’re 65 or 75 years old.”

He says to prevent diabetes of the brain and the body, it’s important to make lifestyle changes that feed the brain while maintaining stable blood sugar and insulin levels.

“If your brain is functioning normally, but it’s starting not to work normally, that’s the time to start thinking about doing something about it,” Dr. McCleary said. “If you lose weight, you can get the glucose metabolism back to normal. If you can do that before you injure brain cells permanently, I predict that you should be able to reverse the changes in your brain.”

He says people with a family history of Alzheimer’s disease, or those who have had a head injury that leads to memory loss should get tested by doing a simple glucose tolerance test once in awhile.

“If your insulin glucose improves, then probably your brain health will improve as well, but it’s better to do it early on even if everything is still functioning than waiting until the nerve cells are starting to die because once they do, they don’t get replaced,” Dr. McCleary said.

Dr. McCleary says if insulin resistance could be minimized by making proper food choices, he estimates that 40 percent of Alzheimer’s disease cases could be prevented.

SOURCE: Interview with Dr. Larry McCleary, 19th Annual World Congress on Anti-Aging and Aesthetic Medicine, held in Orlando, FL, April 7-9, 2011