Air conditioning is a sleep saviour when heatwaves have transformed your bedroom into an oven, but it could be the reason why you keep waking up at 3 a.m. This year, research has found that air conditioners can reduce indoor air quality, and now a doctor is warning that the reliance on AC can negatively impact sleep."Sleep is critical for recovery and repair, so anything that impairs respiratory comfort can interfere with the body's ability to fully recover overnight," says Dr Dale Christensen, Chief Science Officer for Climatic Health and Adjunct Associate Professor of Medicine at Duke University Medical Center.But how exactly does air conditioning impair respiratory comfort? I asked Dr. Christensen to explain how AC can impact air quality and disturb your sleep. Plus, how to fix this issue in three simple steps.Key takeaways: At a glanceThe best smart air conditioners with well-maintained filters have no negative effect on indoor air quality, but AC with neglected filters release harmful air pollutants.Airborne pollutants from unkept AC filters can block airwaves, leading to sleep issues such as frequent nighttime awakenings.The CDC says AC filters should be replaced every three months to lower harmful germs and viruses in the air and to reduce your chances of respiratory illness.The three simple fixes: Check and replace your AC filter every three months, increase ventilation in your bedroom, and avoid using room fragrances and products with high VOCs.How air conditioners impact sleepAccording to the United States Census Bureau, 90% of American households use air conditioning to keep them cool in the summer.Dr. Christensen points out that air conditioning systems aren't inherently bad for indoor air quality, as long as their filters are properly maintained."Air conditioning systems that collect and pass warm air through regularly maintained conditioner filters have minimal effects on air quality since the filters have to allow high airflow in order for the system to cool the air," he explains.