Cold Therapy for Weight Loss and Maintenance
A polar dip, the cold plunge, cryotherapy or Wim Hof! Subjecting yourself to cold has interested health gurus and adventure seekers for a long time. There seems to be a renewed interest in a new generation of “biohackers” and alternative medicine practitioners, but why? What’s the point? Well, at PHD we are always looking for lifestyle behaviors that can help our clients to lose weight, maintain weight loss and optimize their lives. Some of the headlines suggest that cold therapy may do just that but does the research really support those claims?
At first glance the headlines look impressive. Cold therapy seems to improve the immune system, increase testosterone, improve circulation and stimulate secretion of hormones such as Human Growth Hormone (HGH) and Norepinephrine (NE). This sounds fantastic but do I need to sit in an ice bath every day for an hour to see these physiologic responses? Probably not, let’s look at what actually happens with cold exposure and how much is really needed to see benefits related to weight loss and maintenance.
When the body is exposed to cold the immediate response is two-fold. The blood vessels in your limbs contract and shunt blood to your core to protect your vital organs. Your body also then increases its metabolic rate by revving up the cellular machinery (mitochondria) and releasing free fatty acids to be burned as well as breaks down glucose in both free (blood glucose) and stored (glycogen) forms. This 30,000-foot view of the body’s response shows the first and most obvious benefit of cold exposure, blood vessel constriction. As published in the research corner video on cholesterol exercising your blood vessels is important to their health and subsequently in preventing plaque from forming in your arteries. While we are better at expanding our vessels with exercise and heat exposure, we tend to avoid cold exposure and therefore never pull this lever. Cold exposure is the yin to sauna exposure’s yang. But to see the real power of cold exposure for weight loss we need to look deeper.
Looking from the deepest intra-cellular level out we see changes from DNA expression, hormone secretion and even “browning of fat.” These three remarkable adaptations to cold exposure best explain the potential benefit of cold therapy. The expression of “Cold Shock Proteins,” increased production of Brown Adipose Tissue (BAT), and secretion of the hormone NorEpinephrine (NE) each play a role in the bold statements of health regarding diabetes improvement, neurocognitive decline prevention and yes, weight loss and maintenance.
Cold Shock Proteins are activated during cold exposure. This epigenetic response to stress is responsible for the genetic changes associated with this healthy lifestyle habit. One example of these changes is inflammation. This study demonstrates reduction in arthritic pain after 1 week of intermittent cold exposure. These studies demonstrate the impressive benefits for diabetics or those with metabolic syndrome/pre-diabetes. We are all told to exercise for our health, but the benefits are so clear for those with diabetes. Unfortunately, many diabetics are unable to exercise effectively due to arthritis, obesity or chronic pain. However, cold exposure can mimic exercise and improve insulin sensitivity as well as increase energy expenditure through a faster metabolic rate! Lastly, these epigenetic changes may be responsible for the shift in the type of fat that your body is composed of which may play a large role in fat mass balance and metabolism.
Brown Adipose Tissue, sometimes called Brown Fat or BAT is a much more metabolically active form of adipose tissue than the traditional storage tissue in adult humans known as White Adipose Tissue (WAT) or simply “body fat.” Brown fat is commonly thought to only exist in high quantities in animals that hibernate and in human babies. Because of its metabolic activity it can keep the body warm without shivering. Its presence seems to allow for tolerance of temperature and nutrient extremes innate to hibernating animals and young humans that can’t shiver or feed themselves yet. It’s like a combination built in heater/refrigerator. However, BAT is actually present in adult humans too but in variable amounts. It seems to be inversely associated with obesity, particularly as we age. This means that lean adults seem to have more of it and this relationship gets stronger as we get older. Women also tend to have more BAT than men as well.
Brown Adipose Tissue can make up between 2.5 and 45% of an adult human’s fat tissue. Because of the metabolic capacity of the tissue if activated it can increase your basal metabolic rate (BMR) substantially. I wrote about the importance of BMR in this post. Through BMR and other mechanisms BAT seems to have the ability to at least to some extent regulate energy expenditure. Maintaining BMR is critical to weight loss maintenance.
Turns out you can increase the activation of the BAT you already have and actually induce some of your WAT to turn into BAT. This is called “browning of adipose tissue.” The simplest way to turn on this mechanism of energy expenditure is to go back to the origin of why we had it in the first place. To keep us warm! That’s right, cold exposure. Exposure to the cold causes an increase in Norepinephrine (NE) through upregulation of cold shock proteins. NE is the signaling molecule that switches on BAT. I wrote about another approach to increase NE here. NE plays a role in other important processes like sleep, mental focus and clarity, stress responses and inflammation. Numerous studies demonstrate the benefits of increases pulses of NE like this one on improvements in depression and anxiety. Our goal here is to improve BMR and maintain lean muscle mass to aid in weight loss and support maintenance.
So, do you have to sit in ice cold water for an hour every day to see the benefit? NO! Although some studies do use that as an intervention, I think it’s a bit impractical for most people and possibly dangerous. When reviewing the literature, it appears that the gene family (TRP) that stimulates the desired response is turned on at different ambient temperatures. The average of those temperatures is 20c/68f. With warmer exposure you’ll see less benefit and with colder you’ll see more. In this study a single 1-hour immersion in various temperatures shows this nicely. When the subjects were exposed to 89-degree water no change in measured markers was observed. When they were exposed to 68-degree water their resting metabolism went up by 93%. When exposed to 57-degree water it went up 350% and NE levels increased by over 500%. Another study looked at cryotherapy in a whole-body chamber compared to cold air and simple ice packs on the skin. They were measuring pain relief from rheumatoid disease and found that ALL groups noticed THE SAME improvement in rheumatoid disease activity. However, cryotherapy had superior pain relief indicating that the more extreme exposure had a stronger effect. While cryotherapy centers are popping up all over and cold plunges are become more common at health spas and even at home there are a number of home therapies that may be just as effective. Some approaches include simply alternating cold and warm showers for a daily exposure. Another approach is filling a bathtub with the right amount of ice to get to your ideal temperature and sit in it for 1-5 minutes and alternate that with a hot shower. Ultimately, like any intervention the one that is best for you is the one that you will continue to do!
In conclusion cold therapy seems to have a powerful effect on our bodies. Our ancestors adapted to tolerate cold historically and we can use this adaptation to help us navigate our modern world challenges. Cold therapy constricts our vessels providing them with a stress not otherwise achieved. Cold therapy works from the inside out to increase BAT function and quantity. It can “brown” white fat and help us lose weight and maintain it through increased BMR, maintenance of lean muscle mass, improved sleep and attitude! If there was a drug that could do all of that it would be a billion-dollar blockbuster. But it’s not. It’s a simple, inexpensive lifestyle hack that can make a significant difference in your life. Try it out! See what you can tolerate. Remember, it gets easier over time. Your body will adapt. It knows how, you just have to give it a reason to remember.
Supporting your Performance, Health, Diet, PHD
Douglas E Lucas, DO
Chief Science Officer
PHD Weight Loss and Nutrition