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Forget wrinkles. To gauge how old your body really is, check your blood pressure.

“Its the number one cause of aging,” says Dr. Oz.

When high blood pressure blows a hole in one of your arteries, your body has to patch it up, either with healthy HDL cholesterol or lousy LDL cholesterol, he says.

If you eat a healthy diet full of lean meat, produce and good fats found in flaxseed oil and nuts, then youre more likely to have a high amount of HDL, which makes a great patch on your artery wall.

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Lousy LDL cholesterol, on the other hand, makes a crackling patch that doesnt last, resulting in a scab, known in the medical world as a thrombosis.

A thrombosis can close off major arteries of the body, increasing your risk of heart attack.

So remember these two things: High blood pressure is like a fire hydrant—you dont want to open up on your arteries—so aim for a reading thats 120 over 80 or less. Number two: Get your cholesterol checked regularly so you know how much healthy HDL you have compared to unhealthy LDL.