Here's a look at some of the top health news being talked about around the U.S. and the world today:

• In a study that seems to capture the collective frustration of women struggling with their weight, researchers said women were underestimating how much they'd need to exercise to maintain their weight as they age. According to a report in the Journal of the American Medical Association, women should exercise at least an hour a day if they want to avoid gaining weight, the Los Angeles Times reported.

• Weeks after the Consumer Product Safety Commission warned consumers about the danger of using baby carrying slings, the San Diego-based company Infantino LLC is taking its sling carriers off the market altogether, ABC News is reporting.

• Years after California voters chose to make the state the first where marijuana could be used legally for medical purposes, they could be moving toward voting on whether marijuana should just be legalized in general.

• The number of babies delivered by Caesarian section last year hit an all time high and is outstripping most industrialized nations, government health officials said Tuesday. With nearly one-third of all births in the U.S. delivered by Caesarean, it's a concern for health experts because it increases health and safety risks for mothers and infants while increasing costs, Reuters reported.

Tina Reed covers health and the environment for AnnArbor.com. You can reach her at tinareed@annarbor.com, call her at 734-623-2535 or find her on Twitter @TreedinAA.