Human heart
Latest about Heart & Circulation
![An illustration render of an endoscopic view of flowing red blood cells (red, disc-shaped) in a vein.](https://cdn.mos.cms.futurecdn.net/Q8443NSFFgreCYkq6DzmNW-320-80.jpg)
If blood is red, why do veins look bluish?
By Donavyn Coffey last updated
Blood is always red, and veins look blue or green because the skin filters light wavelengths differently.
![an elderly man checking his pulse by holding two fingers to his neck and checking the time on his watch](https://cdn.mos.cms.futurecdn.net/v7wZPuRUBKBSM3yLASGKEE-320-80.jpg)
What is a normal heart rate?
By Bahar Gholipour, Nicoletta Lanese last updated
Monitoring your heart rate can help you track your fitness level and overall health.
![A woman has her blood pressure checked by a doctor.](https://cdn.mos.cms.futurecdn.net/6TitDG8kv7EBXWULHZuorP-320-80.jpg)
Why You Should Check Your Blood Pressure in the Morning
By Sara G. Miller last updated
Does time of day matter when it comes to taking blood pressure?
![milkshake](https://cdn.mos.cms.futurecdn.net/mEbqmtky7urgQqQhbb8gv3-320-80.jpg)
Here's What a Single Milkshake Does to Your Blood Vessels
By Rachael Rettner last updated
A chocolate milkshake may be bliss for your taste buds, but it's not so good for your blood vessels.
![Dark chocolate](https://cdn.mos.cms.futurecdn.net/PNav5asVCh8j8J3LUZi4nm-320-80.jpg)
Sweet Therapy: Chocolate May Help Prevent Irregular Heartbeat
By Cari Nierenberg last updated
Eating a few ounces of chocolate a week may be a sweet way to lower your risk of atrial fibrillation, a new study finds.
![A woman pouring water from a bottle into a glass.](https://cdn.mos.cms.futurecdn.net/mBtoPCtifFRDT9fKBjiwyL-320-80.jpg)
Staying hydrated may reduce the risk of heart failure
By Rachael Rettner last updated
Drinking enough fluids is important for numerous bodily functions, including helping the heart pump blood more easily.
![A diagram of the heart and blood vessels](https://cdn.mos.cms.futurecdn.net/pYF5YURHV2xggu6L2Dnjfb-320-80.jpg)
11 Surprising Facts About the Circulatory System
By Joseph Castro last updated
The human circulatory system was once a subject of great mystery, but now, modern science has revealed its inner workings. Here are 11 surprising facts about the human circulatory system.
![The human circulatory system keeps blood, oxygen and nutrients flowing through the body.](https://cdn.mos.cms.futurecdn.net/DxhwcnJpwLPUW7izf6uYVa-320-80.jpg)
The Circulatory System: An Amazing Circuit That Keeps Our Bodies Going
By Kim Ann Zimmermann last updated
The heart, lungs and about 60,000 miles of blood vessels work together to keep blood pumping through our bodies.
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