14 Expired Things You Own

The ritual of deep cleaning doesn't just clear the cobwebs from your ceilings (and your head); it's essential for great health, too. Knowing when to pitch everything from medication to your smoke alarm helps you and your family sleep better, stay safer, heal faster, and more. This room by room guide outlines some surprising expiration dates.

When to toss: Replace your pillows every year. 

Why: Hair and body oils will have soaked into a pillow's fabric and stuffing after a year of nightly use, making it a breeding ground for odor causing bacteria and allergy triggering dust mites. Using protectors can double the life of your pillows.

When to toss: Replace your mattress after 5 to 10 years.

Why: A good mattress lasts 9 to 10 years, according to the National Sleep Foundation, but consider replacing yours every 5 to 7 years if you don't sleep well. A study at Oklahoma State University found that most people who switched to new bedding after 5 years sleep significantly better and have less back pain. (Follow these tips to get the healthiest bed for your back.)

When to toss: Change smoke alarms after 10 years.

Why: After a decade of continual vigilance, a unit's sensors become less sensitive, putting you at greater risk from smoke or fire should a blaze erupt. Test smoke alarms monthly and replace batteries with new ones every year. To safeguard your family, install alarms on every level of your home, in bedrooms, and outside all sleeping areas. Scary stat: One fifth of US homes have smoke alarms that don't work.

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When to toss: Keep air conditioners until they die.

Why: With proper maintenance, including annual servicing, a room or central air conditioner can easily run for up to 15 years, especially if you don't operate it year round, says Bill Harrison, president elect of the American Society of Heating, Refrigerating, and Air Conditioning Engineers. Check the filter at least every 6 weeks, particularly in humid weather. "If dirt covers the filter so you can't see the original material or view light through it, clean it or buy a new one," he says. (Not a fan of using your air conditioner? Check out these natural ways to stay cool this summer.)

When to toss: Replace vitamins after 2 years to maintain their potency.

Why: Independent tests find that most nutritional supplements are good for 3 years if stored in a cool, dry place, says William Obermeyer, PhD, vice president for research at Consumer­Lab.com. Because the product may have been sitting on store or warehouse shelves for a year, chuck it 2 years after purchase if there's no expiration date.

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When to toss: Replace fire extinguishers every 10 years.

Why: Portable extinguishers may lose pressure over time and become ineffective whether or not they've been triggered, says Lorraine Carli, national spokesperson for the National Fire Protection Association. If your extinguisher is rechargeable, have it serviced every 6 years or when the pressure is low. (Look for service companies in the Yellow Pages under fire extinguishers.)

When to toss: Keep water filters 20% longer than normal.

Why: "Filters that make health claims like lead removal are designed to provide a margin of safety in case they're not changed on time," says Rick Andrew, operations manager at NSF International, an Ann Arbor, MI based company that tests filters. (This applies to most drinking water purifiers, including models from Culligan, Brita, and PUR.) Those equipped with expiration indicators (such as trigger lights) last 20% longer than their recommended life so a filter certified to clean 100 gallons actually purifies 120. Filters without an indictor last even longer, cleaning twice the number of gallons claimed.

When to toss: You can hold on to cutting boards indefinitely.

Why: How you sanitize the board—and not its age—is what kills bugs such as E. coli and Salmonella. "The decision to replace one is ultimately based on when you think it looks too beat up," says Brenda Wilson, PhD, an associate professor of microbiology at the University of Illinois at Urbana Champaign. Even a board with deep cracks or grooves is safe if it's sanitized after each use: Wash the board with detergent and hot water; then rinse and flood with a solution of 1 part full strength white vinegar to 4 parts water and let it sit for 5 minutes. Rinse with clean water, pat with a clean towel, and air dry.

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When to toss: Discard contact lens solution after 3 months.

Why: "Once the seal is broken, germs can contaminate bottles that are left uncapped or that lack a backflow device, increasing your risk of infection," says Louise A. Sclafani, OD, an associate professor of ophthalmology at University of Chicago Hospital. Get a new case every 3 months, too.

When to toss: Replace your toothbrush every 3 to 4 months.

Why: The American Dental Association recommends a 3 to 4 month rotation because frayed and worn bristles don't clean as well leaving teeth more vulnerable to decay. (Your toothbrush isn't just for your teeth! Check out these 10 genius beauty uses.)

When to toss: Throw away eye makeup 6 months after opening to prevent infection.

Why: The applicators used to apply mascara, liner, and shadow are repeatedly exposed to bacteria in the air and on your lashes; after 6 months of everyday use, they can overpower the products' preservatives, says John Bailey, PhD, chief scientist at the Personal Care Products Council. Liquid products that don't touch the eyes, such as foundation, can be used for up to 2 years; dry face products like powder and lip items are generally formulated to last at least 3. (Follow these tips to find the best mascara for you.)

When to toss: Discard antibacterial cream after 1 year.

Why: Beyond a year, the antibiotic is probably still good, but the chemical mix in the ointment may start to go bad, which may make the product less effective.

When to toss: You can hang on to dandruff shampoo for 3 years.

Why: Most medicated shampoo will stay effective at least that long if there isn't an expiration date. Adding water to an almost empty bottle to get the last bit from the bottom dilutes preservatives and makes them less effective, so toss the remainder after several days.

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When to toss: Use rubbing alcohol until the bottle is empty.

Why: "Rubbing alcohol practically lasts forever," says Abigail Salyers, PhD, a professor of microbiology at the University of Illinois at Urbana Champaign. Even after exposure to air, the alcohol/water solution remains stable for years, if not decades, and the alcohol kills any microbes that might get into the bottle.

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