In many couples, the same scenario repeats itself: one person looks for a blanket while the other opens the window. And this contrast is far from anecdotal, since it can be explained by very real differences in how each body produces, retains, and perceives heat.
Why is one cold when the other is hot?
This common phenomenon is not simply a matter of comfort or habit. Thermoregulation, that is, the body's ability to maintain its internal temperature, varies from person to person. Not everyone's body produces the same amount of heat, nor does everyone distribute it in the same way.
This explains why, in a couple, two people in the same room or under the same duvet can experience very different temperatures. The sensation is common, but it is often based on concrete physiological factors.
Metabolism plays a central role
One of the primary factors involved is metabolism. The higher the metabolism, the more heat the body produces at rest. Conversely, a lower metabolism can make you feel colder more quickly. The thyroid gland, which plays a role in regulating metabolism, can also influence this perception. The NHS lists feeling "colder than usual" as a common symptom of hypothyroidism.
Blood circulation, body mass and hormones
Blood circulation also plays an important role.Harvard Health points out that several factors can explain a persistent feeling of cold, including low body mass, certain circulatory disorders, or a thyroid problem.
Body composition also matters. Harvard Health explains that fat acts as insulation, while muscle mass helps generate heat. Therefore, two people of different sizes may not experience the same thermal environment in the same way. Hormones also play a role, especially when a thyroid disorder alters energy production and temperature regulation.
Why does this discrepancy occur so often in couples?
This minor domestic conflict is so common because it involves several factors: subjective feelings, comfort habits, and also biological parameters that differ from person to person. Even in the same bed, two bodies don't regulate their temperature in exactly the same way.
This does not mean that there is an absolute rule in all couples, however, medical sources confirm that individual differences in metabolism, body mass, circulation and health status may be enough to explain this very common everyday discrepancy.
When this phenomenon warrants medical advice
In most cases, this contrast between two partners is simply due to normal individual differences. However, if a sensation of cold or heat becomes new, intense, or persistent, Cleveland Clinic recommends paying attention, especially if it is accompanied by fatigue, weakness, or other symptoms.
In other words, having a partner who is always cold or more sensitive to heat isn't necessarily a problem. This everyday disagreement mainly serves as a reminder that everyone's body experiences temperature differently.
If one person feels cold while another feels hot, it's not simply a matter of personality or quirks. Metabolism, circulation, body composition, and hormones can all create a significant difference in how they feel between two people living in the same environment.
