If you thought diabetes was bad before, wait 'til you see what it's been connected to now...

Alzheimer's disease.

I'm not talking about a small risk, either. Turns out that diabetics have DOUBLE the risk of Alzheimer's disease.

(That is... if they live long enough to face any age-related cognitive decline in the first place.)

The researchers who uncovered this connection also found that diabetics had a 75 percent boost in the odds of any kind of dementia at all.

Think you're safe because you don't quite have diabetes yet? Think again: Pre-diabetics also faced a higher risk of dementia, along with anyone who was even showing early signs -- like high blood sugar levels two hours after a meal.

The researchers say their study doesn't show why diabetes increases the risk of dementia -- but it's pretty obvious to me.

Obesity, a major risk factor for diabetes, also happens to be a risk factor for dementia -- especially if you put those pounds on in mid-life (or earlier) and spend the next few decades dragging them around everywhere. (Read more here.)

Diabetics also have high levels of overall inflammation -- another risk factor for dementia.

For the icing on the cake, one of the key drugs used by millions of diabetics -- metformin -- can rob the brain of essential vitamin B12. And as I just told you, low levels of this nutrient can shrink the brain, short-circuit your memory and bring on dementia.

Bottom line here: If you want to save your brain, start with your belly.