- Aging & Longevity
Lower body temperature extends lifespan
We all know that refrigerating food helps keep it longer. That's because the bacteria and fungi that spoil food grow much more slowly at lower temperatures. Their metabolisms, like that of all living creatures, slow down as they cool down.
Temperature is the key of recent findings by a team of researchers, led by Bruno Conti, at the Scripps Research Institute. Their study found that mice who had lower core body temperatures lived 12% (male) to 20% (female) longer than mice with higher core body temperatures. The difference in temperatures between "cold" and "normal" mice was 0.5-0.9 F (0.3-0.5 C).
Lower body temperature = Lower metabolism
The slowing down of aging had already been demonstrated with cold-blooded animals, like fish. Naturally, it was more difficult to see the effect on warm-blooded animals, since there is an internal thermostat in mammals and birds that maintain a more-or-less constant body temperature (a process called homeostasis), and even a small departure from a narrow range can result in the animal's death.
In this study, genetically-modified mice had their hypothalamus, the part of the brain that regulates body temperature, gear down the mice's body temperature lower.
Although this experiment was not performed on humans, one could surmise that a similar effect on humans, especially those who had slowed metabolisms due to caloric restriction (i.e. low-calorie diets). 95% of people have a body temperature between 97.5F (36.2C) and 98.9F (37.2C).
However, with a lower body temperature come a generally weaker immune system and the propensity to put on weight, so a lower body temperature isn't something that we should all be necessarily wishing for.