How artery-smart are you? In other words, how well do you understand the aging effects that high blood pressure, high cholesterol, and other health threats have on your arteries?

Here's a one-question quiz to help clue you in. Which of the following poses the greatest threat to your arteries?

  1)  An elevated blood pressure of 160/90 mm Hg
  2)  An elevated LDL (bad) cholesterol level of 200 mg/dL
  3)  An elevated helping of fried zucchini sticks
  4)  An elevated amount of time spent on the couch

Blood pressure of 160/90 mm Hg is more than three times more of a threat to make your arteries dysfunctional than any of the other conditions. That doesn't mean you should go ahead and stay camped out on the couch or ignore unhealthy cholesterol values. It just means that your blood pressure may be the most important number you know, other than your spouse's birthday, especially if your blood pressure is higher than 160/90.

Optimally, you want to keep your blood pressure at 115/75. That's the level at which you'll see the least aging. Of course, there are many ways to lower your blood pressure, including medications, physical activity, and diet. Losing weight helps, too. Being overweight not only increases blood pressure but also puts you at risk for diabetes. How close are you to the body ideal? Use this RealAge tool to find out.