Spinach is widely considered by dietitians to be great for your heart and vascular system. Now, scientists have come up with a way to use the leafy green to pump blood to heart tissue. A team from the Worcester Polytechnic Institute was able to manipulate a spinach leaf so that it could actively grow human heart tissue, and blood could pump through its vessels. They hope to use this method to grow replacements for tissue damaged by heart attacks and other cardiac injuries. Watch the video above to see how it works.