For all the new medical knowledge we gained this year, the stories that resonated most with readers are the ones that emphasized how much we still don't know about our own bodies and minds. Many address the same questions we've struggled with for decades — and will continue to do so for the foreseeable future.

Why do so many young people continue to kill themselves? Why do we age and is there a way to slow it down? Why is America's drug problem spiraling out of control again? Below is a look at some of the most popular Washington Post stories in 2015 as determined by you, our readers.


Doris A. Fuller with daughter, Natalie, in 2004, soon after publication of their book “Promise You Won’t Freak Out.” (Courtesy of Doris A. Fuller)

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  • A doctor discovers an important question patients should be asked. I remember a visiting palliative-care physician’s words about caring for the fragile elderly: “We forget to ask patients what they want from their care. What are their goals?” I pause, then look this frail, dignified man in the eye. “What are your goals for your care?” I ask. “How can I help you?”

Peter Thiel, head of Clarium Capital Management LLC and founding investor in PayPal and Facebook, speaks during an event on Feb. 2, 2011. (David Paul Morris/Bloomberg)
  • Tech titans’ latest project: Defy death. For centuries, explorers have searched the world for the fountain of youth. Today’s billionaires believe they can create it, using technology and data. A look at what visionaries like Peter Thiel, Sergey Brin, Sean Parker and others are doing to save us.

Ben Yeager with his mother, Anne, at his 2014 graduation. (Courtesy of Ben Yeager)
  • What happened when this college student drank too much, too quickly. "My skull felt like an eggshell. A wound covering nearly half my face had dried to the upholstery and peeled off when I lifted my head to look around. My pockets, which might have contained evidence of what I’d done, or where I’d been, were empty. I put my hand to my face, which had started to ache, dully at first and then in hot stabs. I felt the warm stickiness where I’d thrown up on the cushions before passing out again."

Valerie Mack, left, is comforted by family friend Carla Stormy Efaw. Mack lost her brother, Sammy, to a heroin overdose. (Marvin Joseph/The Washington Post)
  • The heroin epidemic's toll: One county, 70 minutes, eight overdoses. The United States averages 110 overdose deaths from legal and illegal drugs every day. The heroin death toll has quadrupled in the decade that ended in 2013, according to the Centers for Disease Control and Prevention. By all accounts, it has only grown worse since. In Washington County, there have been more than 50 fatal overdoses this year.

Jeffrey Sank with his stepmother, Catherine Shaer, a retired pediatrician whose advice helped lead to his proper diagnosis. (Family photo)

(Courtesy of Kimberly Almarode)
  • He went from a playful little boy to a zombie. Why wouldn't doctors listen? As she grabbed her car keys and sprinted out of her office, Kimberly Almarode struggled to control the terror that surged through her body. Her son’s preschool teacher had just called to say that Almarode’s 4-year-old son, Bentley, had fallen asleep in a classroom playhouse and teachers were having trouble rousing him.

Read more:

It turns out parenthood is worse than divorce, unemployment — even the death of a partner

With $45 billion pledge to charity, Mark Zuckerberg and wife imagine ‘a world without suffering from disease’

The myth of sugar-free drinks, candy: Study shows they can wreak havoc on teeth, too

Happiness won’t help you live longer (but unhappiness won’t kill you either)

Neighbors file ‘extraordinary, unprecedented’ public nuisance lawsuit against autistic boy’s family

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