The fragmentation of health care—why so many specialists? New Merck Covid pill curbs early disease but fails test in severely ill; Molnupiravir sells for 40 times what it costs to make, as government gears up to stockpile millions of doses; The “Goldilocks Effect” of iron when it comes to heart risk; When a Covid shot goes too deep into your shoulder joint; Subbing sugar with Splenda stokes appetite, undermines weight loss efforts; Vitamin C promotes “mental vitality” in young adults; Pregnenolone for brain and pain; Drugs improve bone density, but exercise boosts bone strength; Are NSAIDS a no-no before colonoscopy?