The Connection Between Sugar and Alzheimer’s Disease

Research links a nutrient-poor Western-style way of eating with cognitive impairment—issues with thinking, learning, and memory. And we’re not just talking the garden-variety brain fart. Research suggests that a steady diet of sugary, processed foods can mess with insulin in the brain. This may trigger what some experts call type 3 diabetes, aka Alzheimer’s disease. Suzanne de la Monte, MD, a neuropathologist at Brown University in Providence, Rhode Island, whose team coined the term type 3 diabetes, was among the first to uncover the link between insulin resistance in brain cells and a high-fat diet. (Check out this MIND diet that has been shown to reduce your risk of Alzheimer’s by up to 53 percent; cutting excess sugar is a key component.)
In a paper published in Current Alzheimer Research, la Monte reviewed the growing body of evidence suggesting that Alzheimer’s is fundamentally a metabolic disease in which the brain’s ability to use glucose and produce energy is impaired. The evidence, she writes, suggests that Alzheimer’s has “virtually all of the features of diabetes [mellitus], but is largely confined to the brain.”In one study, Dr. de la Monte and her team disrupted the way rats’ brains respond to insulin. The rats developed all of the brain damage seen in Alzheimer’s disease. For example, areas of the brain associated with memory became clotted with toxic protein fragments called beta-amyloid plaques. The rats were unable to learn their way through a maze.

People with type 2 diabetes are significantly more likely to suffer from Alzheimer’s.

While the disease doesn’t necessarily cause Alzheimer’s, researchers believe that both diseases may share the same root: insulin resistance, which can be caused by eating too much sugary, fatty junk food. When researchers fed healthy men and women a high-saturated-fat diet loaded with refined grains and sugary foods for a month, their insulin levels rose—and the levels of beta-amyloid in their spinal fluid rose significantly, an Archives of Neurology study reported. A control group on a low-saturated-fat/healthier-carb diet showed reductions in both. Dr. de la Monte’s research is ongoing, but the implications are clearly pointing toward an adverse connection between sugar consumption and Alzheimer’s.The best protection against “sugar brain?” Getting sugar smart. The Express Plan replaces brain-draining fat and carbs with the nutrients a healthy noggin needs. Of course, your taste buds need love, too. Once you reset them, you’ll find that whole, nutritious foods pack the perfect amount of sweetness. You’ll experience that for yourself when you start the plan. For another, an easy Alzheimer’s-fighting diet trick, check out this spice.

ANNE ALEXANDER for Rodale Wellness