Whether your lenses are supposed to last a day or a month, it's not a good idea to save a few bucks by stretching out their life span, says Thomas Steinemann, an associate professor of ophthalmology at Case Western Reserve Medical School, in Cleveland: "Even when you clean and disinfect them, lenses and lens cases become coated with germs and protein over time."
At the very least, wearing contacts past their prime can irritate your eyes, forcing you to wear clunky glasses while your eyes recover. At worst, you can develop an infectious corneal ulcer that leaves scar tissue, reducing your vision or―in extremely rare cases―causing permanent blindness. Replacing lenses with new ones as directed will ensure that you see clearly and avoid issues with your eyes.
2 of 11Greg Clarke
Popping Your Husband's Sleeping Pill
Risk Rating: 4
It's so tempting. You're tossing and turning, and his sleeping pills sit on the nightstand, promising a quick fix. But you're better off counting sheep, because the same pill that sends your spouse safely to slumber can have a very different effect on you, says Rick Kellerman, M.D., president of the American Academy of Family Physicians. "When the doctor wrote the prescription, he took into account your husband's overall health and any other drugs he might be taking," says Kellerman. When you use someone else's medication, you run a greater-than-average risk of experiencing dangerous drug interactions and adverse side effects.
If you consistently have trouble falling asleep, try homespun fixes, like limiting caffeine and listening to soothing music or white noise. Or see your doctor for your own prescription.
3 of 11Greg Clarke
Going Barefoot in the Gym Shower
Risk Rating: 2
If you've forgotten your flip-flops and need to rinse off, you can probably get away with this. Still, there is a chance that going barefoot in a public shower will leave you with an unwelcome souvenir. Fungi thrive in warm, moist environments, and if you pick up one on your feet, it can lead to athlete's foot or even onychomycosis, an infection that turns toenails hard and yellow, says Jane Andersen, a podiatrist and a spokesperson for the American Podiatric Medical Association. Plus, if you have any small cuts on the bottoms of your feet, a virus could sneak through, causing a painful plantar wart or, less commonly, a bacterial infection. So wear your shower shoes, but if you didn't toss them into your gym bag, don't skip the workout.
4 of 11Greg Clarke
Not Finishing a Course of Antibiotics
Risk Rating: 5
After a couple of days on antibiotics, you may feel rejuvenated, recovered, and ready to head back to work. Great―but don't skip those last few pills. Even though you feel vastly better, if you haven't finished the course of medication, there may be some survivors among the bacteria you began killing off, and they can multiply. "Researchers have figured out how much, how often, and how long you need to take the antibiotics to kill all the bacteria," says Rick Kellerman, M.D. Take the medicine until the bottle is empty.
5 of 11Greg Clarke
Trying on Pierced Earrings in the Store
Risk Rating: 1
If your piercings are completely healed and have no redness or cuts, you can most likely try on those cute hoops without any problems. But if you have new piercings, don't put anything through them that hasn't been properly cleaned with alcohol or peroxide. The reason: You never know if the last person who tried on the earrings also had unhealed piercings. "Freshly pierced ears―holes that are less than six weeks old―may contain live skin cells, pus, or even blood, which can carry viruses and other transmittable infections," says Kelly M. Cordoro, a clinical instructor of dermatology at the University of California, San Francisco.
6 of 11Greg Clarke
Eating Food Past Its Expiration Date
Risk Rating: 2
The risk is usually low, and specifics vary from food to food. But when in doubt, throw it out. Since food packaging can carry different dates (use by, sell by, and best if used before), knowing when an item has gone bad can be tricky.
With milk, for instance, keeping the refrigerator adequately cold and discouraging carton slurping (which introduces bacteria) are more important than the date. With deli meats, however, the date is key. Sliced turkey or ham that has been around too long (more than two weeks past the date with a sealed package, or three to five days after opening) can be contaminated and, in the worst case, cause a potentially lethal bacterial infection called listeriosis. Packaged foods eaten after their expiration dates will probably just taste bad, not harm you.
7 of 11Greg Clarke
Eating Unwashed Fruit
Risk Rating: 5
That apple from the roadside stand looks so luscious, you want to bite right into it. But if you don't take an extra few seconds to wash it off, you could be swallowing a lot more than juice―for example, soil that contains bacteria, bird feces, insect residues, and good old dirt. If you get some animal waste in a bite, it can lead to a salmonella or campylobacter infection, which can cause fever, diarrhea, and abdominal pain. "Always wash fruits and vegetables before eating, whether they're from farm stands or they're organic or conventionally grown," says Sam Beattie, a food-safety extension specialist at Iowa State University, in Ames.
8 of 11Greg Clarke
Waiting a Few Years Between Physicals
Risk Rating: 1
Depending on your age and sex, as long as you're in good overall health, a yearly physical examination isn't necessary. "What's most important is to have a physician who knows your health and background," says Rick Kellerman, M.D. So if your primary-care doctor is just a random name you plucked out of a directory and you haven't ever spoken at length, schedule an appointment to meet. If you have any health issues, such as hypertension and high cholesterol, your doctor will probably ask to see you again in a few months. If she awards you a clean bill of health, you can wait a few years for your next head-to-toe exam. Talk to your gynecologist or family physician about how often you should come in for a mammogram and a Pap smear. Depending on your age and health history, you can wait anywhere from one to three years between screenings.
9 of 11Greg Clarke
Missing Just One Birth-Control Pill
Risk Rating: 1
You should be OK. But as soon as you can, take the pill, even if that means doubling up the next day, says Vanessa Cullins, M.D., vice president of medical affairs for the Planned Parenthood Federation of America. "If you take two in one day but have been taking them consistently and correctly the rest of the month, you will be protected," says Cullins. You may experience some spotting from taking the pill late or even a little nausea from the double dose.
If you miss two pills in a row or a couple of doses in the course of a month, use a backup method of birth control.
10 of 11Greg Clarke
Having a Glass of Wine While You Are Breast-Feeding
Risk Rating: 1
Go ahead and toast your new baby (in moderation). Both the La Leche League and the American Academy of Pediatrics have stated that it's fine for a breast-feeding mom to have an occasional glass of wine or beer. "Just be sure to watch your baby and see if it affects him," says Rachel Masch, M.D., associate director of the Division of Family Planning at the Beth Israel Medical Center, in New York City. If he seems extra fussy, you may want to stick to seltzer.
Also, contrary to popular belief, the alcohol doesn't get "trapped" in breast milk. It passes out of your system within two to three hours if you're drinking a glass of wine or beer; within 13 hours if you've had hard liquor. If you've inadvertently had a few too many, consider giving the baby a bottle until the liquor is out of your system.
11 of 11Greg Clarke
Swallowing an Extra Pill if a Headache Won't Go Away
Risk Rating: 3
If you pop just one extra for that five-alarm headache, chances are you'll be fine, since there is a safety range built into the recommended dosages. For example, the maximum daily dose for over-the-counter ibuprofen (Advil is one brand) is only half that of prescription-strength ibuprofen. But routinely taking more than the amount listed on the bottle can cause your body to adapt to the painkiller, leading to more intense headaches, as well as the potential for other health problems, says Rick Kellerman, M.D. In addition, too much acetaminophen (sold as Tylenol) has been linked to liver damage.
If you have a headache or some other issue that won't respond to routine remedies, you should have it checked out by your physician to make sure there is no underlying problem.