• Mayo Clinic Minute: How positivity helps your heart

Research shows that positivity is good for your heart health. Dr. Stephen Kopecky, a Mayo Clinic cardiologist, agrees. He says negative feelings that often happen as a result of too much stress may affect how your body functions. Dr. Kopecky has tips on how you can become more optimistic and decrease your risk of some heart-related illnesses.

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"The power of positive thinking is one of the great, neglected benefits we can do for ourselves," says Dr. Kopecky.

When someone is super stressed out, blood flow to the heart decreases.

"It's adrenaline. It's the fight-or-flight response, you know, that you either see something that's going to endanger you and you fight it, or your run like crazy to get away from it," says Dr. Kopecky.

In today's busy world, stress may seem unending, trapping you in a state of constant negativity. But Dr. Kopecky says you can reduce your risk of heart-related illnesses by being more optimistic and reducing stress.

"You certainly can change how your body reacts to it," says Dr. Kopecky.

How? It can be pretty simple. Think of three things you're grateful for before going to bed or when you get up.

"Your child did well in school or you saw an old high school friend, or you played a great game of golf and hit an ace in the hole or something. That practicing optimism over five years in 7,000 patients was shown to reduce their risk of heart attack, stroke and dying," says Dr. Kopecky.

He says thinking about things that you are grateful for any time during the day is shown to help.