In this edition: RFK Jr. turmoil, the rising use of beta blockers and “fibermaxxing.”

MAHA turmoil. Robert F. Kennedy Jr.’s “Make America Healthy Again” movement is a fractious coalition. The hiring, firing and rehiring of Vinay Prasad, leader of FDA’s vaccines and biologics division, shows how key factions don’t always agree. Kennedy faced sharp questions during a tense Senate hearing this week, including on the firing of the CDC director shortly after she was confirmed. Kennedy defended his actions, saying, “These changes were absolutely necessary adjustments.”

Florida moves to end vaccine mandates. The state’s surgeon general said he is directing the Florida Department of Health to eliminate all vaccine directives, including for school children, which would make it the first state to end immunization requirements. Gov. Ron DeSantis said he will work with the legislature to repeal any laws requiring vaccines.

Can you get a Covid-19 shot? It depends. The FDA has authorized this fall’s updated Covid vaccine only for older adults and high-risk younger people. That decision set off confusion about who can get it, where and whether insurance will pay. We break down what we know.

Chill pill? The beta blocker propranolol has become the go-to pill for dealing with stressful situations, from public speaking to first dates to weddings. Musicians and actors have long relied on beta blockers–which slow the heart rate and lower blood pressure–before performing. Now a new generation of stars is spreading the gospel.

Swearing off ultra-processed foods. Amid rising concerns about the health effects, one family tried to stop eating “UPF”s for one month. For them, that meant eliminating all foods with artificial flavors and anything with refined flours, including most crackers and granola bars. Here’s what they learned.

Are you “tanmaxxing”? After years of skin care obsessives preaching the gospel of sun protection, extreme tanning is back. The UV index, developed to help people take precautions against excessive sun exposure, is now being used by some to identify when tanning will produce the most dramatic effect. Tanning devotees are advocating using little to no sunscreen.

Are you “fibermaxxing”? Food companies are packing fiber into everything from soda to doughnuts and snack bars. “Fibermaxxing,” where people post their efforts to load up on fiber, is trending on social media. But emerging research shows that some fibers in these products, especially in high doses, could lead to health problems in some people.

Wegovy cuts heart risk. Novo Nordisk said its blockbuster weight-loss drug cuts the risk of heart attack, stroke or death by 57% compared with Eli Lilly’s Mounjaro and Zepbound. The real-world study used evidence gathered from actual patient experiences rather than a controlled trial, the Danish company said.

This newsletter was compiled by the WSJ’s Health & Science team. Follow us on X @WSJHealth and @WSJScience. Email us by replying to this newsletter.