Can cold showers really help you lose weight? It’s one of the topics you’ll hear Limbo members discuss regularly, whether they love or hate the process because they see proof that it works. Let’s look into the science behind it.
‘Cold water therapy’ – exposing your body to cold water in the pursuit of better health – has become increasingly fashionable recently. While you may hear some TikTok stars now include it in their workout regimes, scientists have researched the topic for years.
Hippocrates, the founding father of medicine, theorised that cold water could reduce the depletion of energy and strength thousands of years ago. Today, there is ongoing research into whether cold water therapy can help people suffering from depression. Limbo’s research department has studied the specific effects cold water has on weight loss over the last three years using the data provided by a suite of devices worn/used by members every day. These devices monitor several vital statistics every day including blood glucose level, heart rate, body temperature, body composition (muscle, fat, water, bone), blood oxygen, movement levels, and more.
The results speak for themselves, but don’t reach for that cold tap just yet – it’s not as simple as cold showers = weight loss. Cold water is one of the tools Limbo members can choose to combine with other habits and choices they learn while optimising their health through an individualised, data-driven program. So we aren’t studying ordinary people fitting cold showers into their daily lives – we’re studying people who are actively going through a guided programme of change with the goal of losing weight. We are currently studying 202 people who are tracking blood glucose and other statistics (including sleep quality) while logging every choice they make around food, drink, activity, and exercise.
Cold showers can help you lose weight
When you step into a cold shower, the nerves in your skin detect cold water and your body experiences a stress response. Your heart rate goes up and you’re given a kick of adrenaline to help you get through what your body thinks may be a life-or-death situation. The other thing that your body increases to help you survive the situation is your blood glucose. Limbo members build cold showers into their routines because, with the data they have from their bodies, they can be confident that the blood sugar generated is fuelled by their stored body fat.
But it's important to note that cold showers help Limbo members lose weight only if they have done other things Limbo coaches them into doing.
The science: how cold showers burn fat
If you’ve seen a Limbo member proudly displaying the blood glucose spikes they get from cold showers, they’ve typically showered while in the fasted state. The physiological fasted state is when blood glucose levels are in a defined range, regulated by the body, without direct access to carbohydrates from food that push levels upwards. This steady level, most often seen during sleep, and what the body strives to stay in during the day, we call the “basal mean”.
Limbo users see it as a steady blue line, within the blue Limbo zone.
In a "fight or flight" reaction — a legacy of our Stone Age physiology, where we suddenly need to confront or run from danger — our bodies need to raise our accessible energy level, very quickly. This basal mean may not be enough, so the body uses a function akin to “emergency overdrive”, with a pulse of adrenaline release, setting off a chain of physiological events that increases our blood glucose level. This readies the body for action and it works instantaneously, because, at the time this function evolved into our physiology, it was literally an issue of survival: if our ancestors encountered a deadly threat, they could not say “hang on a few minutes, so I can eat first” before fighting or fleeing.
While the process is instant, it’s also complex, because the body has to mobilise multiple systems that subtly interact with each other:
1) Adrenaline release
The hormone adrenaline is released by your adrenal glands into the bloodstream.
2) Lipolysis
The adrenaline leads to fat in the form of free-floating fatty acid (FFA) being released from fat stores – adipocytes – into the bloodstream.
3) Ketone bodies
When the FFAs reach the hepatocyte cells in the liver, they are converted into ketone bodies.
4) Gluconeogenesis
Ketone bodies are then used to fuel a process called gluconeogenesis (derived from Greek, “generation of new glucose”. This process involves the glycogen stored in the hepatocytes being broken down into glucose molecules.
5) Blood glucose increase
Glucose molecules are then released into the bloodstream, raising the body’s blood glucose — seen as a spike. This glucose is used to ‘power’ the body’s flight or fight reaction.
This miraculous choreography of body systems happens almost instantaneously, and is the reason why Limbo users see the elevation in blood glucose — an upward spike in their line — as a result of the cold shower. By taking a cold shower, we can mimic a fight-or-flight situation, where our body’s ancient mechanisms kick in. As part of a weight loss regimen, we can harness this process as another tool for burning fat.
See it in action
Here's Limbo's founder Pat Phelan, showing how he uses cold showers as part of his routine to lose weight and gain energy.