A computer-generated image of red blood cells. Nitric oxide—known by the formula NO—is so vital for humans’ internal physiological processes that it was crowned Molecule of the Year in 1992. It plays ...

Human evolution is often told as a tidy story of adaptation, yet some of our most familiar body parts still defy straightforward explanation. From the jut of the human chin to the curve of the outer ...

While the human body doesn’t replace itself every seven years in a uniform way, it does engage in constant renewal.

Folic acid, also known as vitamin B9, is an important B-vitamin with many vital functions in the human body. It was ...