Ultraprocessed foods make up more than half of the calories consumed daily in the United States and in Britain. (Freepik) By ALICE CALLAHAN On Tuesday, in a series of three review papers published in The Lancet, 43 public health experts from around the world issued a call for government policies aimed at reducing the consumption of ultraprocessed foods which, they write, are driving global increases in obesity and chronic diseases. The papers compile years of evidence on the

Walking for exercise in New York, June 1, 2024. A new study suggests exercise may be especially beneficial for older adults at higher risk of Alzheimer’s disease. (Nicholas Sansone/The New York Times) By DANA G. SMITH Walking a few thousand steps a day can slow cognitive decline in older adults who are at increased risk of developing Alzheimer’s disease, according to research published this month. Getting about 3,000 to 5,000 daily steps was advantageous compared with doing l

Glasses of wine at Frog, a wine bar in New York, Sept. 14, 2024. Heavy drinking is tied to earlier and more severe brain bleeds, a new study found. The paper, published Wednesday, Nov. 5, 2025, in the journal Neurology, examined the link between alcohol and intracerebral hemorrhages — the deadliest, most disabling type of stroke. (Marissa Alper/The New York Times) By SIMAR BAJAJ Heavy drinking is tied to earlier and more severe brain bleeds, a new study found. The paper, publ

Nearly 20 percent of Americans 45 and older have knee osteoarthritis. (Patricia Voulgaris/The New York Times) By JEN MURPHY Nearly 20% of Americans 45 and older have knee osteoarthritis. Worldwide, the number is predicted to increase nearly 75% by 2050, because of aging, population growth and obesity. Knee osteoarthritis is a long-term, degenerative condition that can’t be reversed. It develops in four stages as cartilage in the joint wears down, eventually leaving the bones

A.I. search tools, chatbots and social media are associated with lower cognitive performance, studies say. What to do? (Derek Abella/The New York Times) By BRIAN X. CHEN Last spring, Shiri Melumad, a professor at the Wharton School of the University of Pennsylvania, gave a group of 250 people a simple writing assignment: Share advice with a friend on how to lead a healthier lifestyle. To come up with tips, some were allowed to use a traditional Google search, while others cou

A woman walks for exercise in New York, March 13, 2024. A new study suggests that going on longer walks may have more health benefits than taking the same number of steps a day over multiple short walks. (Nicholas Sansone/The New York Times) By SIMAR BAJAJ A new study suggests that going on longer walks may have more health benefits than taking the same number of steps a day over multiple short walks. Hundreds of studies have shown that higher step counts are tied to lower ri

Tylenol pills in New York on May 22, 2025. Ken Paxton, the Texas attorney general, sued the makers of Tylenol on Oct. 28, claiming that the companies hid the risks of the drug on brain development of children. (Eric Helgas/The New York Times) By REBECCA ROBBINS, AZEEN GHORAYSHI and J. DAVID GOODMAN Ken Paxton, the Republican attorney general of Texas, sued the makers of Tylenol last week claiming that the companies hid the risks of the drug on brain development in children. T

For an activity most of us spend about a third of our lives doing, there’s a lot scientists still don’t understand about sleep, including why we evolved to do it in the first place. (Hoi Chan/The New York Times) By CAROLINE HOPKINS LEGASPI For an activity most of us spend about a third of our lives doing, there’s a lot scientists still don’t understand about sleep, including why we evolved to do it in the first place. But experts do know that we wouldn’t survive without it, a