Woman holding up an eye mask and smiling for the camera
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Eye masks, whether made of gel-filled plastic, herb-filled silk or utilitarian cotton, serve a variety of functions. An eye mask covers the area around the eyes, extending in most cases to the temples and down onto the cheeks. Depending on its function, the mask may or may not have cut-outs to allow you to see through the mask. Most masks feature some sort of fastening to keep the mask securely over your eyes.

Reduce Swelling

Go Ask Alice!, the online health column of Columbia University, reports that you can relieve puffiness around and underneath the eyes by applying a soothing, cool eye mask. Store gel-filled masks designed for this purpose in the refrigerator. Pull one out whenever you need it, and allow it to rest on your puffy eyes for 10 to 20 minutes or until the gel no longer feels cool. Some of these masks feature soothing herbal fragrances, such as lavender, to enhance relaxation.

Relieve Sinus Pain

University of Maryland Medical Center reports that some with chronic sinus congestion accompanied with a headache may find relief with heat and pressure. Float a gel eye mask in a bowl of hot water for a few minutes to transfer soothing, moist heat to these painful areas. For sinusitis with pain after exposure to cold, wet weather and aggravated by warmth, use a cold eye mask while lying down with your head propped up.

Block Light

The Schiffert Health Center of Virginia Tech recommends using a sleep mask to block light that might otherwise interfere with sleep. Light signals your body that it's time to wake up, while your internal clock responds to darkness by making you sleepy. A 2010 Chinese study of patients in an intensive care unit found participants who wore a sleep mask and ear plugs had elevated levels of melatonin, the hormone that helps control sleep, less arousal, and more rapid eye movement (REM) time.