My least favorite Sunday chore is washing my bed sheets, as this requires unmaking and remaking the bed when I could be doing something more fun with my time.

It's annoying, particularly if you don't have a washer or dryer. But it's important to your health and for maintaining good hygiene.

Bed linens come into close contact with your body as long as you're in bed every night, and your bodily fluids seep into the sheets while you sleep, Mary Marlowe Leverette, a laundry expert for About.com, told ATTN:. That includes your sweat and even more disgusting stuff, which builds up in your bed over time if you don't wash your sheets:

"During sleep, we continue to perspire, and body oils and soil are released. It is possible to find saliva, urine, genital fluids, and fecal matter in the fibers. If the [linens] are not washed regularly, and the occupant has scratches or wounds, they can be come infected. Athlete's foot and other fungi can be transferred from fabrics. Infrequent cleaning of sheets and pillowcases allows the fluids to seep into the pillows and mattresses, and those are MUCH more difficult to clean than tossing sheets in the washer."

You also shed skin cells in your bed, which attract dust mites, microscopic bugs that feast off human flesh, Marlowe Leverette said. ATTN: previously reported that millions of dust mites live in your bed, eat your dead skin flakes, and make your mattress heavier over time. Their excrement can also cause asthma and allergies. All of this calls for frequent washing, Marlowe Leverette said.

"The excrement of the mites can cause breathing problems for those with allergies and asthma, but can easily be removed by washing in hot water. By not washing linens frequently, the oils and fluids build up and embed in the fibers, making them much more difficult to remove. If you have ever pulled some sheets from the linen closet, and they smell slightly rancid and stale, that is body soil left in the fibers because the sheets were not cleaned thoroughly."

To maintain a clean living space, help prevent allergies, and stay clean, the best thing to do is wash your sheets once a week in hot water, Marlowe Leverette advised:

"Ideally, bed linens should be washed every week using the hottest water recommended for the fabric. If the weather is extremely hot, and the sleepers perspire heavily or the sleepers are ill, more frequent washings are recommended."

Watch Deep Look's video below about dust mites — if you dare: