Resource: Cold Exposure

Of all the techniques out there the most interesting and POTENTIALLY effective (no studies in weight loss as far as I am aware) is the Wim Hof technique.  It is a breathing, mind and cold water exposure that is being studied more and more and has interesting effects for overall wellbeing. You can find more here –


The theory behind cold exposure is pretty simple.  When we are exposed to the cold our body needs to increase its metabolic rate to generate heat and to do that it needs to burn fuel like a fire, and that fuel is calories.  Hence we lose weight.  There is also an extra part to this which is that the type of fat changes.  Most peoples fat is white fat, which is bad.  But there is brown fat too, which is the type of fat babies have, and this is good fat generally because it generates heat for us and hence burns calories but it could also be anti-inflammatory, good for our blood sugars and a few other perks.  So the theory is that cold exposure forces your body to turn white fat into a half-brown version of fat.

Some people do this via cold showers, ice baths, immersing themselves in a nitrogen gas or sitting in cold air con half naked.  Certainly, I have had patients swear by it and it is also the case that there may be a wide range of other benefits to cold exposure like feeling more alert and awake. But when it comes to weight loss –  is this true?

There have been a number of studies done in mice and rats supporting these theories that cold exposure increases their metabolic rate and conversion to brown fat, but there was no actual weight loss because they just ate more to compensate. Also, they had to be exposed to quite cold conditions for 1-8 hours a day, three times a week, which for most people is impossible.

In humans, we just don’t have much data yet to confirm nor deny this method. There have been a few small trials to show that cold exposure can increase the amount of brown fat activity and reduce our body fat.  One trial from Japan that went for 6 weeks exposing 51 young men to 2 hours a day of 17 degrees lost about 5% of their body fat.  But that is 2 hours a day, which again for most people is a bit unrealistic.

So really it is too early to say but I look forward to seeing more studies on this.  But remember it is simply an addition to the overall healthy food, movement and mind changes you need to make, it is not a magic bullet.  If you feel it benefits in regards to waking you up and trimming off a bit of body fat then go for it but do it safely. There have been cases of people passing out and drowning in the intense cold exposure events like ice baths and nitrogen gas so be smart and be supervised. Also, there may be some medical conditions like blood pressure and heart disorders which may struggle in extremes of cold so please see your doctor about it.


You might be surprised or perhaps not surprised to learn that pollution around us increases our risk of being overweight and of getting conditions like type 2 diabetes. In fact, some studies are now calling it a catalyst for obesity, meaning it speeds up the process.  One study of 700 pregnant women found that those with higher levels of pollutants in their body from the environment around them, like air pollution, had children with 2.5 times more fat mass than those who were not around pollutants.

There are also chemicals called EDCs or Endocrine disrupting chemicals, like BPA are often found in various products like plastics and cosmetics.    These act like synthetic hormones on our cells and can cause a range of health concerns.  There is now a range of EDCs called obesogens because we know they can lead to obesity.

Substances like these EDCs, nitrogen-oxide, polycyclic aromatic hydrocarbons and many others have profound biological effects on how our hormones work, can cause inflammation in our bodies and disrupt normal cell function.  Some also theorise that when we cannot get rid of the pollutants fast enough the body intentionally stores them in our fat because that is where it will do the least damage.

So what can we do about it?  Well the obvious answer is to try to minimise our exposure where possible and it may help, but there are actually no studies I could find to show that avoiding exposure will have major effects on weight loss.  Hence to be clear this is more of an assumption that it may help.  There is a little bit of evidence to show that when we start to lose weight we release these stored pollutants from the body fat stores into our blood.  This is really interesting because there was a fear that when the body releases these fat stores of pollutants that it will cause lots of diseases, but in fact this study showed the opposite because our body also produces lots of natural antioxidants at the same time and then excretes the pollutants, which enhanced heart health and reduced oxidative stress and inflammation.  So once again our bodies are awesome.

Avoiding these pollutants is easier in some ways like buying safe cosmetic products, not using plastic bottles or other containers and staying away from air pollution like traffic.  Sometimes though this can be tough in today’s world where lots of areas and things are exposed do what you can.  If you cannot change some situations then I don’t want you to become really frantic or worried about it, that will not help your health journey – do what you can but still live your life.  Fortunately, various health bodies are pushing governments to ban these and for some, it is slowly working.  In 2001 the Stockholm Convention was an international agreement to remove a lot of these chemicals.  Sadly the USA was one of the few countries do not yet accept this, but most other countries have. So there is still a lot of work to be done, so in the meantime find that sensible space where we are cautious about them and avoid what you can but not becoming overwhelmed by it.