Even small excess concentrations of carbon dioxide in the bedroom can impair sleep quality, impair cognitive function, and increase cardiovascular risks. The researchers of Waseda University (Japan) came to this conclusion. The study results were published in the journal Science and Technology for the Built Environment (STBE).
The international team analyzed 17 previously published studies and 22 experimental data sets. All of the studies looked at how bedroom air quality affects sleep quality and health.
The results showed that when CO2 levels in the air rise to 1,000 parts per million (ppm), sleep patterns begin to change. Optimum conditions for overnight rest are observed at concentrations no higher than 800 ppm.
The authors note that current building codes provide only half of the required ventilation. To maintain safe levels of CO2, at least eight liters of fresh air per second per person is needed, double the current standard.
Poor bedroom ventilation increases the risk of heart disease, daytime sleepiness and cognitive decline. Therefore, indoor air quality standards for residential areas need to be revised, explained study leader Professor Mizuho Akimoto.
Previous studies have shown that lack of oxygen (hypoxia) in the brain causes a stress reaction; the sympathetic nervous system is activated, the level of cortisol and adrenaline increases, the work of the heart accelerates, and the blood vessels narrow.
Inadequate ventilation also leads to sleep fragmentation and increased blood levels of inflammatory markers (such as C-reactive protein). These factors can contribute to hypertension, coronary heart disease and stroke.
Translation:Euromedia24.com-in:
