What Do Germs Grow Best in, Hot or Cold Weather?

Germs in Food

One of the common places to find harmful germs is in food. Germs in food thrive in warmer conditions 1. This is the reason refrigeration of food is necessary. It prevents contamination and the health risks that eating unrefrigerated foods can cause.

Airborn and Contact Germs

The germs commonly associated with illness (the common cold, for example) are more active and grow in warmer temperatures (this is the main reason hospitals keep their indoor temperatures so cool) 3. Despite the old myth that colder weather causes sickness, bacteria are much more active in warmer weather. The spread of illness during the colder months is attributable to the congregating of people indoors.

Bottom Line

Nearly all germs thrive in warmer conditions. To keep infection down, it is helpful to keep both your food and your living conditions cool.