There’s actually a scientific reason why so many older people retire to warm places like Florida and Arizona to avoid snowy winters and freezing temperatures. As humans, our ability to adapt to cold weather conditions weakens as we get older, and we become more sensitive to cold as the years go on.
Now, scientists from the University of Utah Health may have discovered new therapies for cold sensitivity that could also even treat obesity. The researchers also found and traced the circulatory patterns of acylcarnitines, a waxy lipid, and discovered that the liver plays an important role in cold adaptation.
The research was published online in the journal Cell Metabolism.
The researchers, with senior author Claudio Villanueva, an assistant professor of Biochemistry at Utah Health, began their study by observing circulatory levels of acylcarnitines in mice.
By tracking acylcarnitines in the blood stream, the research team found that lipid levels increased in younger mice as they were exposed to colder temperatures, but in older mice acylcarnitines levels stayed stagnant.
The research team tracked the acylcarnitines as they made their way through the circulatory system and found that the lipids originated in the liver.
As the lipids circulated, they were broken down and metabolized in small, energy-intensive tissues, like brown fat.
Brown fat is found in both mice and humans, but mice have larger quantities of it. Brown fat is considered a “good fat” and is a key part of warding off cold sensitivity.
Scientists gave older mice a single dose of L-carnitine, a nutritional supplement. The dosed up older mice were able to adapt better to colder temperatures, even withstanding temperatures that would normally trigger hypothermia.
By dosing the mice with L-carnitine, the researchers were able to help “fuel” the brown fat and in turn, the older mice could adapt better to colder temperatures.
This exciting research could not only help treat cold sensitivity but also combat obesity and find new ways to jumpstart healthy weight loss.
“The idea is to increase fuel utilization to drive the energy demanding process of adapting to the cold. If we can find a way to tell the body to expend more energy than it is taking in, the calories lost can lead to weight loss,” said Villanueva.