Human heart

Inside your body there’s a bustling highway with your beating heart at the center. Learn all about your body’s 60,000 miles of microscopic blood vessels, 5 to 6 quarts of blood, and the sundry passengers (lymph, blood cells, nutrients and more) that ride it every day.

Latest Updates

Space Radiation Doesn't Seem to Be Causing Astronauts to Die from Cancer, Study Finds

By Rachael Rettner

That may be true for the short missions astronauts have gone on so far. But Mars will be a different story.

Low Levels of 'Bad' Cholesterol May Have a Downside

By Rachael Rettner

When it comes to "bad" cholesterol, lower is usually better. But a new study suggests it may be possible for cholesterol levels to be too low.

Sitting in Front of the TV May Be Worse for Your Heart Than Sitting at a Desk

By Rachael Rettner

People with desk jobs may not need to feel so guilty about all those sedentary hours in an office chair.

Man Had a Nearly 5-Foot Wire Left in His Body After Heart Procedure, Lawsuit Claims

By Rachael Rettner

A Nevada man is suing his doctor for allegedly leaving a nearly 5-foot wire in his body for more than a decade.

Rare 'Flash Fire' Ignites in Man's Chest Cavity During Surgery

By Rachael Rettner

Scalpel,. Check. Sponge,. Check. Fire extinguisher...check?

Infertility Linked to Dangerous Heart Condition in Pregnancy

By Stephanie Pappas

Women undergoing fertility treatments may be at increased risk of a dangerous pregnancy condition called peripartum cardiomyopathy.

Erectile Dysfunction Drug May Help Treat Heart Failure

By Rachael Rettner

A drug for erectile dysfunction may also help treat heart failure, a preliminary study in animals suggests.

Scientists 3D printed a heart the size of a rabbit's using human tissue.

How Scientists 3D Printed a Tiny Heart from Human Cells

By Yasemin Saplakoglu

It has four chambers, blood vessels and it beats — sort of.

Med School Cadaver's Heart Was In the Right Place (But Her Other Organs Weren't)

By Mindy Weisberger

This unusual condition went undetected during the woman's lifetime.

Drinking Sugary Beverages Linked with Early Death

By Rachael Rettner

A new study finds that drinking sugar-sweetened beverages is tied to an increased risk of early death.

What the New Egg Study Means for the Beloved Breakfast Food

By Rachael Rettner

Eggs are back in the news, with a new study concluding that regular consumption of the beloved breakfast food may increase the risk of heart disease after all.

Why Are More Young People Having Heart Attacks?

By Rachael Rettner

Heart attack rates are increasing in what may seem like an unlikely group: adults in their 20s and 30s.

Broken-heart syndrome weakens the muscles of the heart, causing its left ventricle to enlarge. The heart takes on a shape like a “takotsubo,” a Japanese fishing pot used to trap octopuses. The condition is also known as takotsubo cardiomyopathy.

Broken-Heart Syndrome May Stem from the Brain

By Yasemin Saplakoglu

The brain decreases its chatter, the heart weakens and balloons up

Why Men Who Can Do 40 Pushups May Have Better Heart Health

By Rachael Rettner

The ability to do a lot of pushups may be a sign not only of strength, but also of good heart health, a new study suggests.

A "heart-shaped foreign body" appeared on a child's X-ray after she swallowed a metal pendant.

Here's Why a Perfect Heart Shape Showed Up on a Girl's X-Ray

By Rachael Rettner

An unusual X-ray shows a cartoonish heart seemingly floating in a child's esophagus.

Here's How Poor Sleep May Hurt Your Heart

By Rachael Rettner

A new study may have uncovered why a poor night's sleep is bad for your heart and blood vessels.

Ice cream tubs in the frozen food aisle.

Eating 'Ultraprocessed' Foods Linked with Early Death

By Rachael Rettner

So-called "ultraprocessed" foods — which are high in salt, sugar and other additives — are linked with an increased risk of early death, a new study finds.