Have you ever wondered why it's always cold inside an airplane no matter what the climate is like at the destination you're flying to?
There are many reasons why the temperature in the airplane cabin is always cold, both objective and subjective.

A study published by the American Society for Testing and Materials (ASTM) found that high cabin temperatures can lead to the risk of passengers fainting.
According to this study, when the plane increases altitude above the ground, lung ventilation or blood flow to the brain will decrease due to immobility, drowsiness and gas accumulation in the abdomen. This can cause passengers to faint. The study shows that high cabin temperature will "trigger" this condition.
On a flight with hundreds of people, each body has a different perception of heat. Therefore, to avoid risks, the crew must always keep the temperature inside the cabin colder.
In addition, the air in the plane is already dry, so the temperature control needs to be turned low to help people not get dehydrated, and to avoid passengers getting sick or nauseous.
Passengers complained of the cold, but the crew "liked it" because flight attendants and pilots often have to wear many layers of clothing and move around, moving around the cabin a lot makes them feel hotter than passengers.
Finally, each individual experiences temperature differently even at the same temperature. One person will feel hot while the person next to them will be begging for an extra blanket in the airplane cabin.