High blood sugar levels make beta amyloid protein—found in people with Alzheimer’s disease—more toxic to the cells that line blood vessels in the brain, according to a new study published in the Journal of Alzheimer’s Disease. High blood sugar is receiving increased attention for its role in Alzheimer’s, so much so that Alzheimer’s disease is also known by some experts as type 3 diabetes.

“While neuronal involvement is a major factor in Alzheimer’s development, recent evidence indicates damaged cerebral blood vessels compromised by high blood sugar play a role,” noted David Busija, PhD. “Even though the links among type 2 diabetes, brain vessels, and Alzheimer’s progression are unclear, hyperglycemia [high blood sugar] appears to play a role.”

The researchers used an animal model to determine that the viability of cells lining blood vessels in the brain decreases by 40 percent when exposed to high blood sugar. This damage is thought to be due to oxidative stress from the mitochondria—the powerhouses of cells. They call for aggressive control of blood sugar levels in diabetic patients to protect against such damage.

Current guidelines for normal blood sugar levels are less than 100 mg/dL, but some experts say that even lower blood sugar levels of 75 to 85 mg/dL are most protective. Indeed, even this study found that so-called normal blood sugar levels increased risk of triggering toxic beta amyloid. What increases blood sugar levels? A diet high in sugar and starchy carbohydrates (read: bread, pasta, pastries, cereal, chips, grains) does.

By lowering your intake of sugar and starchy carbohydrates and replacing these foods with non-starchy fruits and vegetables, lean proteins, and healthy fats, you will achieve healthy blood sugar levels as well as a healthy weight and metabolism.