The first benefit of cold exposure is that it induces mitochondrial biogenesis. What is that? Well first of all let’s talk about what mitochondria are. They are tiny little organelles that live inside all cells of our bodies, some cells will 100 and some will have up to 100 thousand. These organelles are crucial to health and being youthful because they are responsible for producing all the energy that we us from everything from blinking to thinking. Mitochondrial biogenesis is basically a process where we make new mitochondria, and we all day this everyday. The bad news is, is that as we age, our mitochondria get damaged, and worse still, our ability to make new mitochondria through mitochondrial biogenesis diminishes. But a I say, the good news is that cold exposure actually induces mitochondrial biogenesis, it actually triggers the master gene that controls mitochondrial biogenesis, which is PGC1alpha. So that is the first benefit, it induces mitochondrial biogenesis. The second benefit of cold exposure, is that it potentially lowers the amount of free radical damage to our cells and our DNA. You’ve probably heard the expression free radicals, free radicals are also called reactive oxygen species or ROS, and they are a product of everyday living, can’t be avoided and they cause damage to cells and our DNA, and this damage, if not repaired, can lead to all kinds of problems in the future, cancer being one of them. So I mentioned that cold exposure lowers free radical damage, and it does that by increasing antioxidant enzyme activity in the body. So we basically make more antioxidants to deal with the free radicals. Two antioxidant enzyme systems that cold exposure increases are glutathione reductase and superoxide dismutase and both are very potent. And by the way, activating the antioxidant pathways in your body is FAR, FAR more powerful than taking an antioxidant supplement. Okay, the third benefit of cold exposure is that it may help with depression and mood. So cold exposure causes a very robust release of a hormone called norepinephrine, and it’s released in the blood and the brain Norepinephrine is also a neurotransmitter and its associated to focus and attention, and our fight or flight response. It’s been shown that if you deplete peoples norepinephrine, it actually causes depression! So cold exposure increases our release of norepinephrine. The fourth benefit of cold exposure is it can potentially reduce inflammation in the body. So a little bit of inflammation now then is completely natural and healthy, it serves to get get rid of the cause of cell injury and initiates tissue repair. However, when we have too much inflammation from things like too much sugar, that’s when have a big problem. Inflammation is a key driver of aging and is associated to most diseases out there. Now I’ve already mentioned that cold exposure causes a release of the hormone norepinephrine in the blood and brain, and that norepinephrine is associated to focus and mood. Well it turns out the norepinephrine also inhibits the inflammatory pathway by decreasing a key inflammatory molecule called TNF alpha. Too much TNF alpha has been implicated in pretty much all diseases out there. So cold exposure will decrease the amount of TNF alpha we make and therefore may reduce inflammation. The 5th benefit of cold exposure is that it may strengthen our immune system. Having a strong immune system is not only important for fighting off colds, but it’s also critical to help us fight diseases like cancer. To have strong immune system we want to have a good stock of strong healthy immune cells. Unfortunately, as we get older our stock of immune cells will reduce and some of them will stop working too, which is something known as immunosenescence. So if we have a chance to increase our stock of immune cells, we should take it! So cold exposure may increase some of our immune cells, or lymphocyte cells, including cytotoxic T lymphocytes (which play a role in killing cancer cells) and also natural killer T cells that kill viruses and tumor cells. The 6th benefit of cold exposure is that it may help to slow down brain aging and prevent neurodegenerative diseases by protecting and rebuilding brain synapses, synapses are how neurons communicate with each other and how memories are formed. However, I will say this is all theoretical at the moment as the studies demonstrating these effects have been on animals and not humans. So how does cold exposure protect and rebuild synapses? Well it turns out that something called Cold Shock Proteins play a very important role in this process, in particular, one called RNA binding motif 3 or RBM3, and you guessed it, cold exposure increases the activity of RBM3, allowing it to exert its function and help repair these synapses. The good news is, even mild cold exposure is enough to increases the activity of RBM3.