Alzheimer's disease is common and mysterious, well-documented and hidden. Though it affects an estimated 5.4 million Americans today (5.3 million are 65 or older), by 2050 almost 14 million people in the U.S. and 1.4 million in Canada are expected to have this condition.
Although there are medications available, none slows the progress of the disease and none has come close to a cure. In fact, several major drug trials aimed at tackling the disease have shut down prematurely because of colossal failure of the proposed medication. But there is hope due to new clues about diet.
Research published in JAMA Neurology seems to best explain what goes on in the brain when Alzheimer's develops: In that study the two known "bad actors" associated with loss of cognitive function are amyloid? plaques and tau tangles. We don't know that they're the direct cause of the loss of brain functioning, but one hypothesis holds that the formation of plaques may trigger conversion of tau into a toxic version of itself; the toxic tau then makes the plaques even worse, and those two scramble transmissions of info and disrupt memory, emotions and more. Another hypothesis holds that it is inflammation, often worsened by excess sugar.
But how does this all get started? That's the trillion-dollar question! (The yearly cost of payments for health care, long-term and hospice care for people with Alzheimer's are projected to hit over $1.1 trillion in 2050.)
Type 3 Diabetes
New research indicates that inflammation is worsened by dysfunction of glucose metabolism in the brain. That's what's behind the newly coined phrase, "Alzheimer's as Type 3 Diabetes." Here's the current research on glucose levels and your brain:
1. Increases in blood glucose levels are related to higher brain glucose levels, especially in your last decades of life.
2. Higher brain levels of glucose—overwhelming levels—are a precursor to changes in neurological functions. Those changes happen before symptoms of Alzheimer's appear and seem to be associated with formation of plaques and dysregulation of tau.
3. A study in a recent issue of the journal Neurology reports that researchers tested more than 1,600 folks for five biomarkers of inflammation (fibrinogen, albumin, white blood cell count, von Willebrand factor and Factor VIII) when they were around 55 years old. Then, 24 years later, researchers gave those same participants a brain scan and memory test. Folks who had previously elevated levels of three or more biomarkers ended up with an average of 5 percent lower volume of their hippocampus and other areas of the brain associated with Alzheimer's disease. They also had lower scores on the memory test.
4. And then there's the obstructive sleep apnea connection. A new study shows that older folks with OSA are at increased risk for Alzheimer's. Turns out, OSA is associated with glucose intolerance and insulin resistance, whether or not a person is obese. And glucose intolerance and insulin resistance cause elevated glucose levels in the blood and eventually in the brain. That then leads to neuron function disruption and formation of plaques and toxic tau protein—Type 3 diabetes!
What this means for YOU if you are one of the 100 million Americans with prediabetes or diabetes: Act now to reduce bodily inflammation and restore healthy blood sugar levels.
Your brain will thank you decades from now, when you're still thinking clearly!
Mehmet Oz, M.D. is host of "The Dr. Oz Show," and Mike Roizen, M.D. is Chief Wellness Officer and Chair of Wellness Institute at Cleveland Clinic. To live your healthiest, tune into "The Dr. Oz Show" or visit sharecare.com.
(c) 2017 Michael Roizen, M.D. and Mehmet Oz, M.D.