Energy-efficient homes have been lauded as the best thing since sliced bread in recent years, but researchers may have just discovered their kryptonite: as air leakage into and out of the average efficient home decreases, the quality of the air inside decreases so substantially that it actually creates a health risk for residents.

This trend has become so prominent, according to The Guardian, that the number of Brits living with asthma is predicted to double by 2050. Researchers also expect to see a rise in the number of people suffering from allergies and respiratory problems, which they believe will contribute to a higher number of people suffering from lung cancer and heart disease.

The report was funded by Beama, the International Business Times reported, which represents companies that install ventilation systems throughout the U.K.

The potential health risks are especially prevalent in Britain because the country previously set a goal to cut its energy consumption and carbon emissions by 80% by 2050, and efforts are already well in place to make homes throughout the U.K. more efficient.

With an estimated 5.4 million Brits already suffering from asthma, this efficiency goal would likely increase respiratory problems for average British citizens, and cause the rate of respiratory problems to increase by 80%, as well.

The problem at hand isn’t so much about filtering air that makes it past the Great Wall of Energy Efficiency; the problem is that filtration systems currently can’t handle the influx of dust mites and particles from aerosol spray cans that result from closing up one’s house.

Dust mites, for example, typically live and procreate on furniture upholstery and carpets; one ounce of dust can hold as many as 2,000 dust mites, and an energy-efficient ventilation system will simply spread these microscopic pests throughout the house.

Mold is also more likely to grow on damp surfaces — even on items like dishcloths — and these particles are known to cause respiratory problems.

Furthermore, small particles from spray cans — meaning everything from cooking spray to shaving cream — tend to increase in volume and density when a home’s airflow is restricted to conserve energy.

While each of these factors is treatable when occurring in an isolated situation, the three factors combined can present serious health risks — especially as people spend more and more time inside their homes, and these homes begin more and more to resemble gigantic airtight Tupperware containers.

If nothing else, it seems that this study emphasizes a point which NBC News recently touched on: “Researchers have known for years that kids can be too clean.”

Maybe now is the perfect time to open up those windows and frolic in the dirt before the weather gets too cold.