Long hailed as a superfood rich in nutrients, researchers have successfully converted spinach into beating human heart tissue.Scientists at the Worcester Polytechnic Institute in Massachusetts washed spinach leaves with detergent to remove the plant’s cells in a process that preserves the plant’s vascular system, which the researchers then seeded with cardiac tissue, according to research published in the journal Biomaterials. After several days, the leaves began to beat like a heart. The scientists ...