Turns out, there’s no such thing as aging gracefully. Humans age at a molecular level in two accelerated bursts—the first at age 44 and then again at 60, according to scientists at Stanford University and Nanyang Technological University in Singapore. In a study published in Nature Aging, researchers followed 108 participants over several years to observe aging changes in their RNA, proteins and microbiomes. They discovered that subjects don’t age gradually. For example, researchers said t...