There's a new bonus to good blood sugar control: better recall. It turns out that dysfunctional insulin -- a problem that allows blood sugar to get out of control -- not only is bad for your organs and arteries, but it might keep you from remembering the name of your prom date, what month it is or who the latest "American Idol" winner is.

One piece of evidence: Men who had low insulin levels at age 50 had a greater risk of Alzheimer's and other types of dementia later in life.

It's not clear yet how impaired insulin response bumps up Alzheimer's risk. But it is clear that the less insulin in the brain, the more it develops the hallmarks of that disease. In fact, researchers at Brown University refer to this low brain insulin problem and the brain changes it's associated with as "type 3 diabetes."

While researchers haven't yet shown how to prevent type 3 diabetes, it's smart to do what you can to control your blood sugar. Brand-new research found that while a low glycemic index (GI) diet is good at improving blood sugar control, a low-carb diet (less than 20 g of carbs per day) is even better.

Ninety-five percent of diabetics on the low-carb diet were able to reduce or eliminate their meds, while 62 percent of those on the low-GI diet did. Both lost weight, which is also key: Obesity is linked to Alzheimer's risk, too.

The YOU Docs -- Mike Roizen and Mehmet Oz -- are authors of "YOU: Being Beautiful -- The Owner's Manual to Inner and Outer Beauty." To submit questions and find ways to grow younger and healthier, go to www.RealAge.com, the docs' online home.

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