Cold Plunging
This article does NOT constitute medical advice.
Consult with your physician before making any changes to your medical plan.
Consult with your physician before making any changes to your medical plan.
Should you cold plunge for health?
Actually, if you want to be healthy, you don't have a choice. If you want to be healthy, and you live outside the tropics, NATURE MANDATES THAT YOU GET COLD. It's built into your genes. You MUST physically expose your skin to cold temperatures to be healthy.
I will explain.
Your brain contains a small cluster of neurons located in the anterior hypothalamus just above the optic chiasm. This cluster is called the suprachiasmatic nucleus (SCN), and it is the master clock of your entire body. The SCN is directly connected to the retinal pathway, and the light that your eyes receive is the signal for this master clock. It is circadian rhythm. At different times of the year and the day your eye receives different wavelengths and amounts of sunlight, thus the SCN makes adjustments to your body. But what adjustments? The SCN controls the type, amount, and timing of hormones for your entire body. Not just some of your hormones...ALL OF YOUR HORMONES. The SCN controls gene expression. You cannot make the right proteins from your DNA unless you get the right light signals. In other words, the light in your eyes DIRECTLY controls your health. Not a little bit, but A LOT. You evolved to receive 100% natural light in your eyes all day long, but your modern environment gives you artificial light 90% of the day according to the U.S. Environmental Protection Agency study. The average person gets proper circadian light only 10% of the day.
What does this have to do with cold?
As the presence of the sunlight after the autumn equinox gets less and less your body begins to transition from signaling the SCN with light to signaling the SCN with cold temperatures through calcium dependent mechanisms. By late autumn your hypothalamus is controlled more by temperature than by light. Your light exposure is still important, but cold exposure becomes more important. Your modern life, however, has given you artificial summer temperatures all year long at 72 degrees fahrenheit in your home, office, car, gym, and all the buildings you frequent. You never give your body the signal that winter is coming. You never experience winter. Our new "modern winter" has low sunlight coupled with high temperature. That's a hypothalamic mismatch, and it's not possible for your hypothalamus to function properly with these mixed signals. You may get depression, sleep disorders, thyroid problems, diabetes, cancer, cardiovascular disease, bowel disease, dementia, anxiety, sex hormone dysregulation, autoimmune disorders, inflammatory disease, and much more. If you live in the tropics you maintain optimal light stability all year long, but if you live at latitude higher than the tropics you don't. Nature evolved so that it is MANDATORY for you to physically expose your skin to cold temperatures after fall equinox and continue with cold exposure until you can expose your bare skin to UV light in late spring and summer. Let's get into UV light and it's relationship to cold now.
Chimps have 3.8 billion nucleotide base pairs in the their DNA. Humans only have 3.2 billion. Chimps have 24 chromosomes. Humans only have 23. How are we so much more highly evolved if we have less genetic material? Well, it turns out that during evolution a gene on chromosome #24 in chimps jumped to chromosome #2 in humans. In this process that gene got amplified into our super power. What is that gene that gives us our superpowers? It's POMC, proopiomelanocortin, that I've talked so much about many times. The POMC gene codes for the POMC polypeptide, and the POMC polypeptide then gets cleaved into several very important chemicals. These chemicals are ACTH, CLIP, alpha MSH, beta MSH, gamma MSH, beta lipotropin, and beta endorphin. But none of that happens without light. Specifically, UV light. In summer you get that light on your bare skin from the sun. But in winter there's no UV light. So where does the UV light come from? It comes from YOU when you get cold. When you get cold you make UV light that is stronger than sunlight in the your mitochondria as a product of reactive oxygen species (ROS) like superoxide, hydrogen peroxide, and the hydroxyl radical. This is the superpower of humans. It's the reason we have such powerful brains compared to the next most intelligent beings...chimps. Humans can absorb more UV light from the sun, make more UV light in our mitochondria, and transform that light into usable energy in our huge energy-consuming brain.
But there's more. POMC doesn't work unless its receptors bind to the hormone leptin. Leptin is produced by the fat cells under your skin. It gets stimulated in two ways: 1.) by UV light from the sun, 2.) by cold temperatures on your skin. Since we didn't get UV light on our skin in winter during evolution we evolved to use cold as the signal. Cold stimulates massive amounts of leptin to super charge the POMC pathway. The leptin-melanocortin pathway is an ancient pathway that nature gave us to survive and thrive in winter. But if you don't get cold in winter you can't be healthy. There just isn't enough sunlight in winter. Nature mandates that we get cold during low sunlight winter conditions. Additionally, when your skin temperature reaches 50-55 degrees your body releases a chemical called endothelial nitric oxide synthase (eNOS) through the initial vasoconstriction of blood vessels to preserve heat followed by the vasodilation of blood vessels when warming. That process disconnects your circadian clock from light and reconnects it to temperature. Light still matters but temperature now matters more. In other words, cold exposure literally rewires how your hypothalamus views time and seasons. This eNOS surge increases nitric oxide production, and the nitric oxide then supercharges POMC activation by further enhancing leptin. The supercharged POMC increases production of alpha MSH which feeds back to signal further increase in eNOS. The whole system works in a synergistic feed back loop. Furthermore, the large amount of leptin binding to neurons in the hypothalamus completely shuts down neuropeptide Y (NPY). That means you don't crave carbs and you don't get hungry. It also suppresses agouti-related peptide (AgRP) which further suppresses appetite. It's a complete package of health benefits.
So, how do you get cold exposure in a practical way in your day-to-day modern life? Michael Phelps trained in a swimming pool that was 50-55 degrees. Lance Armstrong had industrial freezers installed in his house where he trained on a stationary cycling simulator. The Russians secretly trained their athletes in cold temperatures for decades. NASA studied the cold-adapted Sherpas of the Himalayan mountains for years so that they could learn how to cold-adapt astronauts. But you can't just jump right into very cold temperatures when you've been living a warm-adapted life for decades. You have to start slowly and do it safely. Generally, it's recommended to start by cold plunging your face in the sink for a couple weeks. Then progress to ending your shower with cold water for a minute or two. After some time you can progress toward full body submersion in a tub of cold water after you have done some research on cold plunging and have talked to your doctor. The skin needs an extended signal of 50-55 degrees fahrenheit to activate the ancient leptin-melanocortin pathway. It will take time for you to safely work up to full body submersion in 50-55 degree water. Go slowly. Study the literature on cold thermogenesis. Talk to your doctor.
You will notice a difference after just a couple weeks. But I'm not gonna lie to you. IT'S FUCKING DIFFICULT. Especially in the beginning. You're hate gonna it at first. You're probably gonna hate me for suggesting it. But after a few weeks of consistency it begins to become the most relaxing form of meditation that you can imagine. You feel so good. You sleep better. You're more patient, more productive. Your blood glucose comes down. Your blood pressure comes down. Your ketones go up if you're fat adapted. Pain subsides due to beta endorphin production. Be patient with yourself. It takes 24-36 months to become fully cold adapted. If it gets too hard then back off a bit. Take a day off, or do a shorter duration, or use a warmer temperature. Keep educating yourself on cold thermogenesis. Good luck on your journey.
Actually, if you want to be healthy, you don't have a choice. If you want to be healthy, and you live outside the tropics, NATURE MANDATES THAT YOU GET COLD. It's built into your genes. You MUST physically expose your skin to cold temperatures to be healthy.
I will explain.
Your brain contains a small cluster of neurons located in the anterior hypothalamus just above the optic chiasm. This cluster is called the suprachiasmatic nucleus (SCN), and it is the master clock of your entire body. The SCN is directly connected to the retinal pathway, and the light that your eyes receive is the signal for this master clock. It is circadian rhythm. At different times of the year and the day your eye receives different wavelengths and amounts of sunlight, thus the SCN makes adjustments to your body. But what adjustments? The SCN controls the type, amount, and timing of hormones for your entire body. Not just some of your hormones...ALL OF YOUR HORMONES. The SCN controls gene expression. You cannot make the right proteins from your DNA unless you get the right light signals. In other words, the light in your eyes DIRECTLY controls your health. Not a little bit, but A LOT. You evolved to receive 100% natural light in your eyes all day long, but your modern environment gives you artificial light 90% of the day according to the U.S. Environmental Protection Agency study. The average person gets proper circadian light only 10% of the day.
What does this have to do with cold?
As the presence of the sunlight after the autumn equinox gets less and less your body begins to transition from signaling the SCN with light to signaling the SCN with cold temperatures through calcium dependent mechanisms. By late autumn your hypothalamus is controlled more by temperature than by light. Your light exposure is still important, but cold exposure becomes more important. Your modern life, however, has given you artificial summer temperatures all year long at 72 degrees fahrenheit in your home, office, car, gym, and all the buildings you frequent. You never give your body the signal that winter is coming. You never experience winter. Our new "modern winter" has low sunlight coupled with high temperature. That's a hypothalamic mismatch, and it's not possible for your hypothalamus to function properly with these mixed signals. You may get depression, sleep disorders, thyroid problems, diabetes, cancer, cardiovascular disease, bowel disease, dementia, anxiety, sex hormone dysregulation, autoimmune disorders, inflammatory disease, and much more. If you live in the tropics you maintain optimal light stability all year long, but if you live at latitude higher than the tropics you don't. Nature evolved so that it is MANDATORY for you to physically expose your skin to cold temperatures after fall equinox and continue with cold exposure until you can expose your bare skin to UV light in late spring and summer. Let's get into UV light and it's relationship to cold now.
Chimps have 3.8 billion nucleotide base pairs in the their DNA. Humans only have 3.2 billion. Chimps have 24 chromosomes. Humans only have 23. How are we so much more highly evolved if we have less genetic material? Well, it turns out that during evolution a gene on chromosome #24 in chimps jumped to chromosome #2 in humans. In this process that gene got amplified into our super power. What is that gene that gives us our superpowers? It's POMC, proopiomelanocortin, that I've talked so much about many times. The POMC gene codes for the POMC polypeptide, and the POMC polypeptide then gets cleaved into several very important chemicals. These chemicals are ACTH, CLIP, alpha MSH, beta MSH, gamma MSH, beta lipotropin, and beta endorphin. But none of that happens without light. Specifically, UV light. In summer you get that light on your bare skin from the sun. But in winter there's no UV light. So where does the UV light come from? It comes from YOU when you get cold. When you get cold you make UV light that is stronger than sunlight in the your mitochondria as a product of reactive oxygen species (ROS) like superoxide, hydrogen peroxide, and the hydroxyl radical. This is the superpower of humans. It's the reason we have such powerful brains compared to the next most intelligent beings...chimps. Humans can absorb more UV light from the sun, make more UV light in our mitochondria, and transform that light into usable energy in our huge energy-consuming brain.
But there's more. POMC doesn't work unless its receptors bind to the hormone leptin. Leptin is produced by the fat cells under your skin. It gets stimulated in two ways: 1.) by UV light from the sun, 2.) by cold temperatures on your skin. Since we didn't get UV light on our skin in winter during evolution we evolved to use cold as the signal. Cold stimulates massive amounts of leptin to super charge the POMC pathway. The leptin-melanocortin pathway is an ancient pathway that nature gave us to survive and thrive in winter. But if you don't get cold in winter you can't be healthy. There just isn't enough sunlight in winter. Nature mandates that we get cold during low sunlight winter conditions. Additionally, when your skin temperature reaches 50-55 degrees your body releases a chemical called endothelial nitric oxide synthase (eNOS) through the initial vasoconstriction of blood vessels to preserve heat followed by the vasodilation of blood vessels when warming. That process disconnects your circadian clock from light and reconnects it to temperature. Light still matters but temperature now matters more. In other words, cold exposure literally rewires how your hypothalamus views time and seasons. This eNOS surge increases nitric oxide production, and the nitric oxide then supercharges POMC activation by further enhancing leptin. The supercharged POMC increases production of alpha MSH which feeds back to signal further increase in eNOS. The whole system works in a synergistic feed back loop. Furthermore, the large amount of leptin binding to neurons in the hypothalamus completely shuts down neuropeptide Y (NPY). That means you don't crave carbs and you don't get hungry. It also suppresses agouti-related peptide (AgRP) which further suppresses appetite. It's a complete package of health benefits.
So, how do you get cold exposure in a practical way in your day-to-day modern life? Michael Phelps trained in a swimming pool that was 50-55 degrees. Lance Armstrong had industrial freezers installed in his house where he trained on a stationary cycling simulator. The Russians secretly trained their athletes in cold temperatures for decades. NASA studied the cold-adapted Sherpas of the Himalayan mountains for years so that they could learn how to cold-adapt astronauts. But you can't just jump right into very cold temperatures when you've been living a warm-adapted life for decades. You have to start slowly and do it safely. Generally, it's recommended to start by cold plunging your face in the sink for a couple weeks. Then progress to ending your shower with cold water for a minute or two. After some time you can progress toward full body submersion in a tub of cold water after you have done some research on cold plunging and have talked to your doctor. The skin needs an extended signal of 50-55 degrees fahrenheit to activate the ancient leptin-melanocortin pathway. It will take time for you to safely work up to full body submersion in 50-55 degree water. Go slowly. Study the literature on cold thermogenesis. Talk to your doctor.
You will notice a difference after just a couple weeks. But I'm not gonna lie to you. IT'S FUCKING DIFFICULT. Especially in the beginning. You're hate gonna it at first. You're probably gonna hate me for suggesting it. But after a few weeks of consistency it begins to become the most relaxing form of meditation that you can imagine. You feel so good. You sleep better. You're more patient, more productive. Your blood glucose comes down. Your blood pressure comes down. Your ketones go up if you're fat adapted. Pain subsides due to beta endorphin production. Be patient with yourself. It takes 24-36 months to become fully cold adapted. If it gets too hard then back off a bit. Take a day off, or do a shorter duration, or use a warmer temperature. Keep educating yourself on cold thermogenesis. Good luck on your journey.
This article does NOT constitute medical advice.
Consult with your physician before making any changes to your medical plan.
Consult with your physician before making any changes to your medical plan.
