The concept of Whole Body Cryo-Therapy and other Cryotherapy treatments has received a lot of support over the past few years, but what is it about exposure to cold that makes our body react, and what are the metabolic effects of such exposure?
Cold exposure has been associated with stress reduction because it has been associated with the idea of hormesis. The way that this translates to cold exposure is relatively simple if the body succumbs to a low-dose short-duration stressor, such as the cold, then over time, there will be a cascade of events as the body will adapt and will eventually become a precondition to not reach to some of the larger stressors that it may encounter.
This concept is not new, in fact, the idea that exposure to cold is beneficial for health dates back centuries. Habitual cold exposure is believed to have beneficial effects that extend not only to the body’s metabolic health but could also potentially work positively for the brain’s function. This is because when the body is exposed to cold a chemical, norepinephrine, is produced in the adrenal glands and central nervous system. This chemical has dual functionality as it can act both as a hormone and a neurotransmitter. What is more impressive though is that this chemical’s unique effect is to be its ability to promote the fighting of metabolic-related diseases as well as assist in certain brain function parameters.
Studies in both humans and mice have shown that cold water immersion increases levels of PGC-1 alpha in skeletal muscle. Pgc1 alpha is a protein that regulates mitochondrial biogenesis and is commonly associated with lowering the chances of developing certain diseases such as Alzheimer’s, Parkinson’s, and type 2 diabetes. Norepinephrine on the other hand when acting as a hormone can constrict blood vessels which could be helpful in heat retention.
Heat retention is not the only way that our body can maintain its temperature. Our body can produce its heat in a process called Thermogenesis. Thermogenesis is often a result of shivering since shivering is the body’s way of generating heat. However, Thermogenesis can also occur without shivering, the indirect metabolic heat production. Norepinephrine also plays an important role in thermogenesis as it can act on key proteins that disconnect the normal electrical processes within our mitochondria. The mitochondria which normally produce chemical energy will then switch to directly producing heat, to do so it uses fat.
What is important to remember regarding this is that not all fat can be used for this type of thermogenesis. Brown fat as it is known is a type of fat with darker coloring that reflects the mitochondrial density and previously it was thought that it only appeared in new-borns, however, modern studies have shown that it can be found in adults that are exposed to cold. This type of brown fat appears because of a process known as mitochondrial biogenesis, which is regulated by norepinephrine.
According to a study that looked at how brown fat activity could be increased, healthy young men who wore a cooling suit at 50 degrees Fahrenheit had their brown fat volume increased by 45. This suggests that their brown fat increased more than twofold, as a result, we can deduce that cold exposure can help increase energy expenditure and thus could potentially have metabolic benefits.
Different research exposed its participants to a temperature of 63 degrees Fahrenheit for two hours every day for over six weeks. Their thermogenesis increased by around 58% but the fat decrease was minimal if not non-existent.
Other evidence that resulted from this research showed that cold-induced brown fat activation would potentially affect metabolic health, improve glucose and insulin sensitivity and increase fat utilization. All of this would protect against diet-induced obesity.
A different study also looked at men who underwent prolonged cold exposure in a cooling vest. Only the ones with detachable brown fat saw their energy expenditure increase by 15. One-third of this increase was caused by the oxidation of plasma-derived glucose. Of the men who received an infusion of glucose, only those with detectable brown fat showed an increase in their glucose use. This proved that brown fat is a key player in glucose utilization as it can provide an alternate pathway for glucose.
What other effects can Norepinephrine have?
Apart from all of the effects on the body, Norepinephrine depletion has also been linked with depression and ADHD. As a result, those mental illnesses are often treated with norepinephrine reuptake inhibitors which can block the reabsorption of norepinephrine and thus increase its levels around our neurons.
However, these drugs do not come without risks. For those seeking alternative treatments, exposure to cold can be relatively safe for increasing a person’s norepinephrine levels. Even cold exposure though is not completely risk-free.
Exposure to cold has been shown to have potentially positive effects on the body and increase energy production. This could effectively help with treating the body for certain conditions. Still, the results of the so far studies have been questionable as no concrete evidence exists to suggest that this type of treatment will work for everyone. Cold exposure is also being used to treat certain mental health problems; however, those treatments can come with risks and they are not always effective.
To try it, just Google ‘cryotherapy’ in your town. Or you can do it the old fashioned way with an ice bath, or a cold stream or lake.