1. Ibuprofen could contribute to male infertility when taken in large doses on a regular basis. French scientists gave 14 healthy men, ages 18 to 35, a 600 mg dose of ibuprofen twice a day for six weeks, and a placebo to 17 others. After only two weeks, those taking the anti-inflammatory drug developed compensated hypogonadism, a testicular condition that can lead to infertility. "We normally see this condition in elderly men, so it raises an alarm," says senior author Bernard Jégou. It remains unclear why ­ibuprofen — the active ingredient in Advil and Motrin — might have this effect; compensated hypogonadism normally occurs when the testes don't produce enough testosterone.

2. Grilled food may increase the risk for high blood pressure. Harvard researchers analyzed the diets of some 103,000 people for up to 16 years. Those who ate grilled, broiled, or roasted meats or fish more than 15 times a month were 17 percent more likely to develop high blood pressure than people who ate them fewer than four times a month. And participants who preferred their meats well done were 15 percent more likely to suffer hypertension than those who opted for rarer meats. Lead researcher Gang Liu says that chemicals produced by cooking meats at high temperatures induce oxidative stress, inflammation, and insulin resistance in animals, possibly leading to a raised risk of developing high blood pressure.

3. Ties constrict blood flow to the brain. A German research team asked 15 men to put on a tie, make a Windsor knot, and then undergo three MRI scans: with their collar open and tie loose; with the tie tightened to the point of slight discomfort; and then with it loose again. The scans showed that a tightly secured necktie reduces blood flow to the brain by an average of 7.5 percent. Researchers say tie wearing may have at least a temporary effect on men's brain function, particularly if they have chronic health issues such as diabetes or heart disease.

4. Disinfectants could make children overweight by altering their gut bacteria. Researchers in Canada found that infants who lived in households where antimicrobial disinfectants were used every week were twice as likely — at ages 3 to 4 months — to have higher levels of Lachnospiraceae, a gut bacteria linked in animal studies to increased levels of body fat and insulin resistance. By age 3, those children were more likely to be overweight or obese than kids from homes where surface cleaners and other disinfectants weren't used as regularly.

5. Bottled water almost always contains microplastics. A study of 259 water bottles from the U.S. and eight other countries found that 93 percent were contaminated with pieces of plastic less than 5mm long. The researchers found an average of 10 plastic particles per liter of water. They remain unsure how or when this contamination occurs, or how plastic in the body affects human health. "It's not about pointing fingers at particular brands," says study author Sherri Mason. "It's really showing that this is everywhere, that plastic has become such a pervasive material in our society."

6. Staying up late could reduce your lifespan. Researchers tracked some 430,000 adults for nearly seven years and found that night owls had a 10 percent greater risk of early death than those who woke early. People who burned the midnight oil were also more likely to have chronic health issues such as diabetes, neurological disorders, and respiratory disease. Study author Kristen Knutson says those naturally inclined to rise late feel pressure to conform to other people's schedules, leaving them anxious and sleep deprived. "There's a problem for the night owl who's trying to live in the morning-lark world," she says.

7. Following sports makes you miserable. Using 3 million responses to a happiness-monitoring app and three seasons' worth of results from soccer matches, researchers in the U.K. calculated that the joy fans feel when their team wins is outweighed — 2 to 1 — by the misery they suffer when the team loses. Fans' happiness score — measured on a 100-point scale — jumped about 3.9 points when their local team won. Following a loss, it fell by 7.8 points. Researchers say these "quite dramatic" effects add up over time, and are more pronounced among those who attend matches or expect their teams to win.