Now you have an excuse to skip making your bed when you are running late in the morning. Science says that the sweat we release during the night is a giant breeding ground for dust mites. Allowing the sheets to air for a while may mitigate this gross occurrence.

According to Real Simple, studies show that these microscopic insect-like pests feed on dead human skin cells and love hanging out on moist bed linens. Martin Seeley, CEO of MattressNextDay, based in the U.K., has nearly 40 years of experience in the field of sleep science.

“Given that the average person sweats nearly 500 milliliters per night, your bed environment is the perfect breeding ground for dust mites in the morning,” he says. “That’s why it’s important to leave your bed unmade for at least 30 minutes allowing for better ventilation which helps disperse moisture and reduces the overall humidity in your bed.” All that sweat equates to about 2 cups of moisture, so airing the sheets by procrastinating to make the bed reduces the humidity that helps dust mites breed.

While dust mites don’t directly harm us, they can make exacerbate allergy symptoms. This is particularly important for those suffering from asthma. The American Lung Association reports that dust mites can affect our health in several ways. It’s the excrement of dust mites, the feces and urine, that trigger allergic reactions.

“Ongoing exposure to dust mites at home can impact the health of people with asthma and those who are allergic or sensitive to mites,” explains the organization.

“These allergens can trigger mild to severe allergic symptoms and can be responsible for asthma attacks. A mild case may cause an occasional runny nose, watery eyes and sneezing. In severe cases, the condition is ongoing, resulting in persistent sneezing, cough, congestion, facial pressure or even a severe asthma attack. People with asthma who are sensitive to dust mites face an increased risk of asthma attacks,” says the American Lung Association.

Experts say if you notice any of these allergy reactions, you may want to hold off making your bed as soon as you wake up. Washing sheets frequently in hot water and using a special anti-allergic mattress and pillow protector can also help.