Your eyelids feel heavy for a reason — Surely you’ve experienced the phenomenon of feeling like you can’t possibly keep your eyes open for one second longer when you’re tired — in the predawn hours feeding a newborn or while attempting to stay up and watch your favorite show. Why does this eyelid heaviness happen? There are a…

It could have something to do with an overachieving vagus nerve — One afternoon when she was six years old, Kim Petschek was walking home from school when she stubbed her toe on the sidewalk, resulting in a small — but bloody — gash. The next thing she remembers is waking up on the street, sprawled out face-first on the concrete with…

Despite obvious symptoms, it took me months to realize I had PTSD — and even longer to accept it. Here’s why it’s so hard to recognize and to treat. — “It sounds like you have post-traumatic stress disorder,” my therapist said. I was 21 and sitting across from my therapist on the third floor of the university health center, a box of tissues on the coffee table between us and her bulky copy of the DSM-5 spread out on my…

A brief look into a trendy amino acid — People take supplements for all sorts of reasons — omega-3s for heart health, calcium for strong bones, vitamin B12 for more energy. But rarely is there one supplement that claims to heal seemingly every ailment, from asthma to liver disease. Yet NAC, short for N-acetyl cysteine, is that kind of…

Many people hospitalized from vape-related illnesses reported using THC oil. Here’s what experts know, and how you should proceed. — As of September 17, the Centers for Disease Control (CDC) has reported at least six deaths and 530 hospitalizations from the use of vape products like e-cigarettes and vape pens. The illnesses have spanned 36 states and one U.S. …

The effects may not be long-term, but doctors are seeing more people with screen-related vision problems — If you glance at the news today, order groceries, or schedule a playdate for your child, chances are you’re doing it in front of a screen. Research shows that the average American adult spends up to half their waking hours on a phone or other electronic device. …

A new therapy teaches people to process their trauma as a way to treat chronic pain. Does it work? — Human beings have long sought to understand the basis of pain. Until the late 17th century, pain and disease were considered a byproduct of sin, or something a person endured to test their faith. …

Failing spectacularly in a high-stakes situation is a near-universal experience. Fortunately, there’s plenty of research on how to keep a cool head. — Even now, 10 years later, I still remember the moment with excruciating clarity: During the fourth and final round of a high school regional speech competition, after a full day of flawless performances, I went up to the front of the auditorium for my last speech and froze.

What works, and what doesn’t, in the quest to make yourself more illness-resistant — The same aisle exists in pretty much any drugstore — the one with the powders, pills, chewable tablets, gummies, sprays, and drinks, all claiming to help you stave off or shorten illnesses. It’s a comforting idea — that a heartier defense system is that close at hand — especially if…