Cryotherapy is the popular treatment of exposing the body to subzero temperatures, and it is purported to provide many different benefits to bodily, mental, and holistic health. One of these purported benefits is weight loss. But is it true that cryotherapy could actually aid in the shedding of excess pounds? While research is still in progress, the answer could be yes!
How Does Cryotherapy Work?
To understand how research is progressing, we first have to dig into how cryotherapy works. In a standard cryotherapy treatment, patients step into a cryosauna––a chamber cooled using vaporized nitrogen to anywhere between 200°F to -300°F––for a three to five minute period. Once inside, the extremely low temperatures chill the skin, which sends the body into a natural fight or flight response. To protect the internal organs, blood vessels constrict and redirect blood from the extremities to the core. As a result, the blood becomes suffused with anti-inflammatory proteins and oxygen, excess white blood cells are expunged, and the metabolic rate is boosted. Cryotherapy promotes natural anti-inflammatory response, the release of endorphins, and the reduction of pain and spasms. The two most common types of cryotherapy are whole body cryotherapy, in which all but the head is exposed to frigid temperatures, and localized cryotherapy, in which only a portion of the body is exposed.
Developed in 1978 by Dr. Toshiro Yamauchi, a Japanese rheumatologist, cryotherapy was originally used to assist in the treatment of rheumatoid arthritis. However, it was quickly discovered that there were many other potential applications, and over the subsequent four decades scientists have learned a great deal about the curative benefits of cryotherapy. One of the most enticing of these benefits is weight loss. Cryotherapy advocates suggest that this is done through the previously mentioned boosting of the metabolic rate. But how is the metabolic rate boosted? Through a process known as thermogenesis.
Cryotherapy and Thermogenesis
Though research on cryotherapy has been conducted since at least the early 1980s (most of it centered around––and confirmed––cryotherapy’s alleviation of arthritic aches and pains), many of its purported benefits have only been thinly investigated. Unfortunately, weight loss is one of these under-investigated benefits. However, the little research that has been done has been on the whole quite positive.
A 2018 study in the Journal of Obesity showed that, in an effort to warm itself after exposure to the intense cold, the body burns up fat and calories in the hours post cryotherapy session through the natural process of thermogenesis. The French study noted that single cryotherapy sessions lead to significant decline in a type of fat known as local adipose tissue. This led the researchers to conclude that cryotherapy “may be a viable option for combating obesity and overweight.”
How Does Thermogenesis Result in Weight Loss?
Thermogenesis is the process of heat production in organisms, and it occurs in all warm-blooded animals. In an effort to warm itself after exposure to intense cold, the body burns up fat and calories in the hours post cryotherapy session. The type of thermogenesis produced by cryotherapy is known as “nonshivering thermogenesis,” which is defined as an increase in metabolic heat production that is not associated with muscle activity.
But what does nonshivering thermogenesis have to do with weight loss? Well, this type of thermogenesis turns our typically “white fat” (also known as white adipose tissue) into “brown fat” (also known as brown adipose tissue). White fat is the body’s standard fat––it keeps us warm, provides insulation to the organs, and too much of it can lead to obesity or heart disease. Brown fat, on the other hand, is a special type of fat activated when the body becomes cold.
This brown fat stores energy in a smaller space than white face, and its iron-rich mitochondria is what’s responsible for its eponymous color. As brown fat burns, it creates heat without shivering––thus, “nonshivering thermogenesis.” According to the Mayo Clinic, “Brown fat contains many more mitochondria than does white fat. These mitochondria are the ‘engines’ in brown fat that burn calories to produce heat.” Based on this theory of thermogenesis, cryotherapy advocates suggest that by amping up the body’s metabolic rate a single session of cryotherapy can help burn between 500-800 calories. But are these advocates correct? And are their claims backed up by scientific evidence?
Research on Thermogenesis
A Dutch study found that the type of thermogenesis produced by cryotherapy does indeed turn our typically white fat into brown fat. Trial-goers underwent a 10-day cold acclimation regiment, which resulted in a marked increase in nonshivering thermogenesis. The researchers concluded that cryotherapy “might be an acceptable and economic manner to increase energy expenditure and may contribute to counteracting the current obesity epidemic.” The study did only feature a small sample size of only 17 trial-goers, and so more research is very much needed.
While still too early to confirm whether cryotherapy does indeed work for weight loss, the early data is promising. More research has been conducted on cryotherapy’s other benefits, and these include improved athletic recovery time, relief from arthritic aches and pains, the removal of keloids, deeper sleep, and better moods. Overall, both whole-body and localized cryotherapy have shown themselves to be great options for those looking for non-medical additions to a healthy lifestyle. However, cryotherapy is not recommended for pregnant women, those with high blood pressure, those with major heart or lung conditions, those with poor circulation, or those with neuropathy (nerve disease) in the legs or feet.