What is the link between blood sugar levels and Alzheimer's disease?

There may be a newly discovered bonus to good blood sugar control -- better recall.

Turns out that Alzheimer's disease and the #1 blood sugar disorder, diabetes, share something in common -- something that wreaks havoc on normal brain function -- lack of insulin.

A long-term Swedish study revealed that too little insulin ups Alzheimer's risk. Men with low insulin secretion at age 50 had a significantly greater risk of the mind-robbing disease -- as well as other types of dementia -- later in life. One caveat though is that the link was strongest in men without the gene that predisposes people to Alzheimer's.

Exactly how an impaired insulin response bumps up the Alzheimer's risk isn't clear. But it definitely underscores the importance of diabetes prevention efforts.

Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)
While death rates for cardiovascular disease and prostate cancer have been declining, deaths from Alzheimer’s disease are on the rise. Diets high in sugar have been linked to an increased diagnosis of Alzheimer’s disease. Your blood delivers all kinds of rich nutrients to the brain. But if you have a lot of sugar in your blood, it can cause inflammation. This allows plaque to collect on your neurons, which are where you store your memories. The plaque makes it harder for neurons to fire off signals and causes them to freeze up. Eventually, they are prevented from talking to each other; the information those neurons carry can’t be transmitted or retrieved. When these synapses begin to fail, we begin to see the symptoms of Alzheimer’s.

A fasting blood sugar greater than 100 puts you at a greater risk for Alzheimer’s disease.
This content originally appeared on

Continue Learning about Alzheimer's Disease Causes

Can You Spot the Signs of Early-Onset Alzheimer's?
Can You Spot the Signs of Early-Onset Alzheimer's?
Some 5.7 million Americans—nearly two-thirds of them women—currently live with Alzheimer’s disease, the most common cause of dementia. And we rightly ...
Read More
How do genetics affect my risk for Alzheimer's disease?
Dr. Gary Small, MDDr. Gary Small, MD
There are genetic risks for Alzheimer’s disease. The most common gene involved is called APOE. APOE ...
More Answers
What genes are associated with early onset of Alzheimer's?
Discovery HealthDiscovery Health
The three genes associated with early-onset Alzheimer's are amyloid precursor protein, presenilen 1 ...
More Answers
Are Down Syndrome Therapies Similar to Alzehimer's Disease Therapies?
Are Down Syndrome Therapies Similar to Alzehimer's Disease Therapies?

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.