Most doctors do not make a final diagnosis of high blood pressure until they measure your blood pressure several times (at least 2 blood pressure readings on 3 different days). Some doctors ask their patients to wear a portable machine that measures their blood pressure over the course of several days. This machine may help the doctor find out whether a patient has true high blood pressure or what is known as “white-coat hypertension.” White-coat hypertension is a condition in which a patient’s blood pressure rises during a visit to a doctor when anxiety and stress probably play a role.
Imagine a garden hose hooked up to a spigot. When the hose is flexible and there are no kinks in it, you can turn on the water full blast and it will flow easily through the hose. But if there’s a kink in the hose, the water doesn’t flow as well beyond the kink. And the pressure inside the hose builds up behind the kink. Or imagine there is gunk inside the hose blocking the path of the water. Your arteries are a lot like that garden hose.

Don’t get too excited. Turns out that dark chocolate (at least 50% to 70% cocoa) can give you a boost of a plant compound called flavanol. As with garlic, this antioxidant can raise your nitric oxide levels and widen blood vessels. That can make your blood pressure drop a notch. It goes without saying that a little bit of chocolate is all you need. 
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