Biden Administration appeals ruling that struck down a federal mask mandate on planes and other public transportation: But experts noted the legal dangers of appealing the decision. Read more

New report shows air pollution levels have spiked in recent years: After more than two decades of decreases in overall air pollution levels, the United States recorded the highest ever number of "very unhealthy" and "hazardous" air quality days between 2018 and 2020. Read more

Woman hit by Omicron infection right after Delta infection: A fully vaccinated health care worker for COVID-19 twice in 21 days -- the shortest known time between infections, Spanish researchers report. Read more

Intermittent Fasting: Is It Better Than Typical Weight-Loss Diets? "Time-restricted" eating has become a popular weight-loss tactic, but a new clinical trial finds no benefits in adding it to old-fashioned calorie-cutting. Read more