"Only one thing concerns me," says the doctor to Archie Bunker on an episode of "All in the Family." "Your blood pressure is 170 over 98. That's just a little high. Now, let me ask you, Mr. Bunker, are you the kind of person who gets upset easily?"

"No, no I don't. Ask her," Archie replies, pointing to his wife, Edith.

"Uh, only when he's upset," she says.

"What kind of an answer is that?!" Archie yells at Edith.

"You just answered my question, Mr. Bunker," says the doctor.

Archie's blood pressure was, in fact, not "just a little high." It was sky-high, indicating that his heart was straining to get blood to his organs.

Over time, that can lead to heart attack, stroke, or even kidney failure.

But there's another risky side effect of high blood pressure that many folks aren't aware of: It can cause cognitive decline.

A new study in JAMA Neurology followed more than 1,600 patients ages 70-plus for 10 years. Those with a systolic blood pressure (the top number) higher than 150 mm/Hg had much more cognitive decline than those whose number was below 150.

Folks cruising along under 120 mm/Hg had the least cognitive decline.

So aim to bring your systolic blood pressure down below 120 mm/Hg for both your body and mind.

If it usually hovers just above that, in the 121-139 range, you probably can lower it using regular exercise and a healthy diet. If it's 140 or higher, talk to your doctor about taking medication in addition to making lifestyle changes.