Under the new guidelines, tens of millions more Americans now meet the criteria for having high blood pressure.

Stanford researchers collected motion data from smartphones as a way to measure activity across hundreds of thousands of people to help figure out why obesity is a bigger problem in some countries than others.

The medical school professors were awarded the grants as part of a large-scale National Institutes of Health program to study the biology of how physical activity improves health.

Stanford researchers say that data collected through MyHeart Counts, a heart-health study in which participants transmit information through an app, demonstrates the potential of smartphones to transform the measurement of physical activity and fitness for clinical research.

A survey of hundreds of California high-school students shows that teens don’t understand the risks of marijuana use, and are more likely to smoke it if they have seen marijuana ads.

An international clinical research project that Stanford launched on Sept. 12 aims to find out how to enhance health and overall wellness.

Pediatrician Neville Golden is lead author of new clinical guidelines aimed at helping prevent obesity and eating disorders in adolescents.

A study comparing employment in smokers and nonsmokers showed that by 12 months, smokers were less likely to have found a job than nonsmokers, and those who did earned less than nonsmokers.