This week in Health, we’re chasing nightmares, pushing iron, fighting pneumonia, unveiling a brewing superpower ... and learning about dense breasts. 

MICROGRAPH BY SUSUMU NISHINAGA, SCIENCE PHOTO LIBRARY 

Popeye knew it. Eat iron-rich food, and iron makes you strong. What happens if you don’t get enough? Most of us don’t. Do you get irritable? Exhausted? Here’s what happens. 

Related: Is melatonin safe—and is it giving you nightmares?

PHOTOGRAPH BY DAVID LEVENE, EYEVINE/REDUX 

Isn’t beer bad? Expands the waist? Ushers along dementia? Science has found a superpower inside the suds, one that may fight microbes, tumors, inflammation—and help regulate blood-sugar. What is it?

Related: A 9,000-year-old love affair with beer

But: A Dry November carries big benefits

PHOTOGRAPH BY LIVING ART ENTERPRISES, LLC/SCIENCE PHOTO LIBRARY 

PHOTOGRAPH BY GERARD LACZ, VWPICS / REDUX 

That’s what one ultramarathoner set out to discover. At the beginning it looked hopeless. Did Nicole Teeny catch up? 

Related: Humans were born to run, early fossils suggest

Today’s Soundtrack: Born to Run, Bruce Sprinsteen
Road Diary: Bruce Springsteen & The E Street Bank, watch trailer, now streaming on Hulu and Disney+

Thanks for reading today’s newsletter. It was edited and curated by David Beard and produced by Alisher Egamov. If you want this health newsletter in your inbox next week, sign up here. See you around!