Are dry eyes worse in summer or winter?

Neither season wins for everyone. Winter dries eyes mostly indoors, where heated air loses relative humidity, and outdoors through cold wind. Summer does it through air conditioning, fans, wind and bright sun that makes people squint instead of blinking fully. Which feels worse depends on where you live and how you spend your day. Many people notice the change between seasons most, when the furnace or AC first switches on.

Are dry eyes worse in winter?

For many people in colder parts of the country, yes. The main reason is heat, not cold. Winter air outdoors holds little moisture to begin with. When a furnace, heat pump or radiator warms that air, its relative humidity drops further, because warm air can hold more water than it’s carrying. Spend most of a January day indoors and your eyes sit in very dry air for hours.

• Forced-air vents blow that dry air across the room, and sometimes straight at a desk or bed.
• Car heaters and defrosters aim warm air toward the face on every drive.
• Outdoors, cold wind on a walk, a ski run or a snowy commute pulls moisture off the eye’s surface.
• Shorter days mean more evenings on screens, and people blink less while reading them.

Winter heating and dry eyes goes deeper into indoor heat, and dry eyes from cold air covers the outdoor side.

Are dry eyes worse in summer?

In hot places, they can be. Summer’s drying comes from different sources:

• Air conditioning removes moisture as it cools, and it often runs for months in the South and Southwest.
• Fans and ceiling fans keep air moving across your face, which speeds evaporation from the tear film.
• Wind at the beach, on a boat or on a bike ride does the same outdoors.
• Bright sun and glare off water, sand or pavement make people squint, and a squint isn’t a full blink.
• In dry climates, outdoor afternoons can be very low in humidity even before the AC comes on.
• Pool water and long swims can leave eyes feeling irritated afterward.

Are dry eyes worse in hot weather or cold weather?

Temperature by itself matters less than three other things: how dry the air is, how much it’s moving, and how often you blink. A humid summer day in an air-conditioned office can feel drier on the eyes than a mild, damp winter afternoon outside. A cold, windy morning on a ski lift can feel drier than either. Think about the air your face is actually in, hour by hour, rather than the number on the thermometer.

How the tear film handles each season

The tear film has three layers: an inner mucus layer that helps tears stick to the eye, a watery middle layer, and an outer oil layer that slows evaporation. Every blink spreads a fresh film across the surface. Dry, moving or heated air speeds up the loss of the watery layer between blinks, in any month of the year. What is the tear film explains each layer.

The switchover weeks

Many people notice dry eyes most when the seasons turn. The first cold week of fall, when the heat comes on for the first time in months, and the first hot week of late spring, when the AC starts running all over again, both change indoor air quickly. Eyes that were comfortable last week suddenly feel gritty. Those are good weeks to check where vents point, refill a humidifier and pay attention to blinking.

Habits for each season

Winter:

• Run a clean humidifier where you sleep; see does a humidifier help dry eyes.
• Point heat registers and space heaters away from your face.
• Use the car’s floor vents instead of the dash vents.
• Wear wraparound sunglasses or goggles in cold wind and snow glare.

Summer:

• Angle AC vents toward your chest, at home, at work and in the car.
• Keep bedroom fans on low and not aimed at the pillow.
• Wear sunglasses outdoors to cut glare and wind.
• Drink water through hot days.
• Rinse your face after the pool.

Year-round: take short screen breaks, look across the room and blink slowly a few times.

Using a lubricating drop in any season

Quell’s label lists its Uses as: For use as a protectant against further irritation or to relieve dryness of the eye. It’s designed to reinforce the tear film’s oil layer to help reduce moisture loss, and the directions stay the same whatever the season: Apply 1 drop 3 times per day in each eye. Store the bottle as the label says, Store between 15° to 30°C (59° to 86°F). In summer, that means keeping it out of a hot car; in winter, out of a freezing one.

If your eyes stay dry through every season, or the dryness keeps getting worse, that’s a reason to see an eye doctor. The label is clear about when to stop: Stop use and ask a doctor if you feel eye pain or changes in your vision, if irritation or redness continues, or if the condition worsens or persists for 72 hours.