What makes you Sleepy after Thanksgiving?

CO2 or Trytophan

For years, scientists told us that the reason we feel tired after eating a traditional Thanksgiving meal is that turkey contains tryptophan, a natural sedative. But the staff at CO2Meter have known for years that high carbon dioxide (CO2) levels indoors directly affects us as well.

Could high CO2 levels around the table be the reason everyone feels so drowsy after their Thanksgiving meal?

Does CO2 from crowded spaces make you sleepy on Thanksgiving?

While the idea of Thanksgiving sleepiness is often attributed to a heavy meal or tryptophan in turkey, CO2 levels from crowded spaces can also play a role. When many people gather in an enclosed space such as a dining room or living room, CO2 levels can increase due to collective exhalation. Elevated CO2 levels can contribute to feelings of drowsiness, fatigue, and a general sense of sluggishness. Poor ventilation exacerbates this effect, as CO2 gradually accumulates, increasing the feeling of "stuffy" air.

Although CO2 from crowded spaces is not typically dangerous in a well-ventilated home, it can contribute to the tiredness people often feel after a Thanksgiving gathering.

How do we know?

In 2013, eight of our staff members sat down in the break room to a traditional dinner featuring turkey, dressing, cranberries and all the trimmings. Watch our original Thanksgiving IAQ Test Video here.

Ten years later we decided it was time to re-test using a CO2Meter Indoor Air Quality Monitor. Not only did the CO2Meter team double in size from our 2013 video, but the room space doubled its size as well. 

Watch the 2023 Thanksgiving IAQ Test Video here: 

Here are the results from the study:

CO2Meter Friendsgiving CO2 Levels

A - Beginning of meal. The CO2 levels in the office had settled at 400 ppm when the office opened to 1,000ppm once everyone started to enter and settle in. This is normal every day.

B – Thanksgiving dinner is served. From the time the staff was seated until the meal was over, CO2 levels rose dramatically by the minute! By the end of the meal, the CO2 level peaked at 1,600 ppm! 

C – Cleanup. People began to leave the room. Opening and closing the doors lowered the CO2 levels to about 1,200 ppm.

D – Dessert. Everyone came back into the room, and the CO2 levels returned to their peak of 1,600 ppm. The general consensus was that everyone was sleepier than when the meal began.

E – Experiment Ends. During discussion, we realized that we didn’t have a control group of people who did not eat the turkey, so our results were fairly inconclusive. However, everyone left the room for some fresh air so they could wake up before getting back to work!

Monitoring Indoor Air Quality for a Healthier Thanksgiving

TIM10 Desktop CO2, Temp. & Humidity Monitor l CO2Meter

As you can see from our test results, monitoring indoor air quality at Thanksgiving can help ensure a healthier and more comfortable environment for everyone.

Indoor air quality CO2 meters monitor CO2 levels, humidity, and temperature, providing real-time data to alert you when air quality starts to decline. With a house full of guests, CO2 levels can quickly rise due to increased respiration, potentially leading to feelings of drowsiness and discomfort. By placing air quality meters in key gathering areas, hosts can keep an eye on indoor conditions and take measures to improve ventilation when necessary.

Incorporating indoor air quality meters not only helps mitigate CO2 buildup but also provides valuable insights into overall air quality. This can be especially beneficial if guests are sensitive to poor air quality or have respiratory conditions. Simple steps such as opening windows or using air purifiers when CO2 levels get too high can make a significant difference in maintaining a fresh, inviting atmosphere.

Using indoor air quality meters is a proactive approach that enhances comfort and safety, ensuring your Thanksgiving celebration is enjoyable and worry-free.

We hope that this test may have inspired you to create your own CO2 Thanksgiving experiment at home. Please share your results with us too!

See more indoor air quality monitors here.


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