Stories by Claudia Wallis

Chemicals called phthalates—found in everything from detergent to plastic shower curtains—are tied to lower sperm counts and more miscarriages

A new principle in medicine focuses on understanding patients’ values, not assuming they share your own

For healthy adults who want strong bones, a commonly recommended vitamin doesn’t seem to help, but other things really do

There are different ways to be happy and function well, even if your brain is not typical

Evidence is building that fumes from gas stoves can aggravate lung ailments

A spike in diabetes during pregnancy, worsened by the pandemic, raises the risk of chronic diabetes, heart disease and birth complications

One brain region combines signals from your mouth, gut and blood

Risks for Black, Hispanic and Asian Americans start at lower weights and younger ages than risks for white people

A combination of biological and social factors most likely explain the strong connection

Tragedies such as the ones in Uvalde, Tex., and Buffalo, N.Y., can lead to major depression, PTSD and other lingering mental distress among survivors

Knees and other joints regrow some lost cartilage with some outside aid, research suggests

Injectable weight-loss medicines reduce appetite but raise questions of long-term safety and affordability

Partnerships with top research centers, along with advanced technology, may help local doctors offer patients the latest therapies

If the U.S. Supreme Court fails to uphold abortion rights this spring, more restrictions are likely

A type of clinical trial that tests many therapies at once is being used for COVID and Alzheimer’s

Research suggests virtual sessions can be as effective as in-person meetings

The reasons for unequal patient outcomes may lie in implicit biases at the hospitals that treat them

Over-the-counter analgesics can be quite effective, but high doses have downsides

They could be reduced with targeted exercise and some technological innovations

Standard remedies offer little relief for the itchy rash caused by the plant, but researchers have found promising clues in the immune system

Shorter courses cause fewer side effects and breed fewer antibiotic-resistant “superbugs”

Liquid biopsies show promise for early detection of deadly tumors

Designers should show how well instruments perform across different populations

Using home monitoring and other efficiencies instead of dragging people into hospitals could improve clinical trials after the pandemic