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Shivering is kinda weird right. If you get too cold your whole body starts convulsing and your teeth start chattering and you start to feel like a tight mess.
Well it's not for nothing.
Your body has this amazing ability to self thermoregulate i.e. control its own temperature. It does this using various biological tricks like shivering and sweating. Thermoregulation is important because our bodies need to maintain a relatively stable core temperature in order to function properly.
This is what separates us from the lizards.
Interestingly, the mechanisms responsible for keeping you warm can also be used to burn fat and improve metabolic health.
This isn't actually true in the most literal sense. Your whole body, including your fat cells, don't like to be too cold. When you're in a cold environment the best way to maintain your body's core temperature is to fire up your metabolism.
The best of example of this is when you go for a run or start to exercise. Your body naturally starts to heat up as a byproduct of burning calories. Specifically, your mitochondria, the energy producing organelles in the cell, start to release heat as they metabolize fats and sugars.
Shivering is an involuntary exercise which causes your muscles to generate heat by burning calories.
But it's not the only way ...
Your fat cells can also generate heat by metabolizing the fat that they store.
All fat cells have mitochondria but some fat cells have a far higher density. This means that they have a far higher metabolic capacity and can in turn generate a lot more heat.
Fat cells with high densities of mitochondria make up what is called brown fat whereas fat cells with fewer mitochondria whose primary purpose is to store fat are called white fat. Beige fat tissue exhibits characteristics of both.
Maintaining higher levels of brown fat effectively increases your baseline metabolism and therefore improves your ability to lose weight and stay warm. In addition, beige and brown fat cells, because of their high energy demands, pull glucose out of the bloodstream and reduce the risk of metabolic diseases like diabetes.
Unfortunately, as we age, the levels of brown fat tend to decrease. Babies have lots of brown fat to ensure they can stay warm. Adults however tend to naturally lose brown fat over time.
Fortunately, there are natural ways to increase the amount of brown and beige fat in your body.
Researchers studying brown fat have found that both exercise and cold exposure cause the muscles to excrete hormones which increase the number of brown and beige fat cells.
Cold exposure in particular has shown to be effective in raising brown and beige fat levels likely because of the role brown and beige fat plays in thermoregulation.
So if you're looking to lose some weight, raise your energy levels, and improve your overall metabolic health you may want to explore cold exposure protocols like cold water immersion or cold showers.
Stay chilly!
Nick