Cold Exposure Increases Insulin Sensitivity

Type 2 diabetes, which is reaching epidemic proportions, is characterized by increased insulin resistance. The hormone insulin doesn’t work as well as normally, and so the beta cells in the pancreas must make increasing amounts of it.

Dietary carbohydrate restriction, exercise — especially strength training — and intermittent fasting all promote good insulin sensitivity (low insulin resistance). 

Cold temperatures increase insulin sensitivity

It looks like we can add cold exposure to the list of interventions that increase insulin sensitivity.1

Type 2 diabetes is positively associated with ambient temperature. The warmer the weather, the more diabetes. Up to about 30% of the variation in diabetes can be explained by  temperature.

Curiously, no effect of temperature was seen on obesity, although other studies have found that there is one.

The authors believe that activation of brown adipose tissue (BAT) may contribute to this effect. BAT is a type of fat tissue that increases its metabolism for the sole purpose of generating body heat.

Cold thermogenesis has many health benefits, although helping you to lose weight probably isn’t one of them, for the same reason that aerobic exercise is not very effective for weight loss.

The connection between cold exposure and insulin sensitivity isn’t just an association either: acclimation to the cold causes a substantial increase in insulin sensitivity.2

Eight people with type 2 diabetes were exposed to cold temperatures, 14 to 15 C (57 to 59 F) for 6 hours a day for 10 days. Insulin sensitivity increased 43%.

BAT activation was minor. But there was a large increase in the GLUT4 receptor, the proteins in skeletal muscle that take up glucose from the bloodstream. These same GLUT4 receptors are activated by exercise — again, especially by strength training.

Cold showers and other cold exposure should be quite effective in increasing GLUT4 receptors and improving insulin sensitivity. Since water conducts heat far more than air, you wouldn’t need to spend 6 hours in the shower to achieve this effect. The heat conductivity of water is about 24 times as great as for air. (0.58 vs 0.024).

If the relation were linear, then 15 minutes in a cold shower of ~58 F would give the same effect.  But I’m guessing that actual time would be much shorter since the body reaches a lower temperature faster.

I take a cold shower every morning. I’ve measured the water temperature as about 56 F in the winter, at about 66 in summer.

Iron metabolism is also associated with insulin resistance

A recent study found that the more iron in a person’s body, the greater the insulin resistance they had.3 

These findings suggest that body iron stores and/or iron metabolism–related factors may contribute to the induction of IR early in the pathogenesis of T2DM. Of note, body iron stores can easily be influenced by low-cost interventions such as phlebotomies or dietary interventions. Therefore, iron metabolism, and particularly effects of iron on adipose tissue, represents an interesting feature of the metabolic syndrome that deserves further investigation.

In rats that are bred to have type 2 diabetes, restricting iron in the diet, or lowering their iron via phlebotomy, improves all indicators of diabetes, including insulin, triglycerides, glucose, cholesterol, and free fatty acids.4



Both cold exposure and lowering iron levels can increase insulin sensitivity. Since insulin sensitivity is a key marker of health and decreases in aging, keeping it it high (low insulin resistance) can markedly improve health.

To use cold exposure, take 5 to 15 minute cold showers; alternatively, being outside in colder weather with light clothing would work too.

To lower iron, see my book, Dumping Iron.

PS: Check out my Supplements Buying Guide for Men.

  1.  Speakman, John R., and Sahar Heidari-Bakavoli. “Type 2 diabetes, but not obesity, prevalence is positively associated with ambient temperature.”Scientific Reports 6 (2016).
  2.  Hanssen, Mark JW, et al. “Short-term cold acclimation improves insulin sensitivity in patients with type 2 diabetes mellitus.” Nature medicine 21.8 (2015): 863-865.
  3.  Wlazlo, Nick, et al. “Iron Metabolism Is Associated With Adipocyte Insulin Resistance and Plasma Adiponectin The Cohort on Diabetes and Atherosclerosis Maastricht (CODAM) study.” Diabetes care 36.2 (2013): 309-315.
  4. Minamiyama, Yukiko, et al. “Iron restriction improves type 2 diabetes mellitus in Otsuka Long-Evans Tokushima fatty rats.” American Journal of Physiology-Endocrinology and Metabolism 298.6 (2010): E1140-E1149.

Leave a Comment:

Cold Exposure Increases Insulin Sensitivity | Technology and Longevity Feed says September 7, 2016

[…] Original Article: Cold Exposure Increases Insulin Sensitivity […]

Arren Brandt says September 7, 2016

There is also the possibility of buying thermo-caps and thermo-gloves if you cannot access cold water. They sell different ones on Amazon and Ebay, mostly directed to chemo patients. I tried the Thermo-helmet, that was an oddly satisfying sensation.
IMO Fasting + cold showers is a real hit. I wonder if the cold speeds up the fasting so to speak. In Paleoish times you probably fasted at winter, so to speak.

Uncle Maffoo says September 7, 2016

This reminds me of the time in college when I kept my dorm room window open for several weeks in January, right as the semester started. Hey, I like sleeping in a cold room, and still do! You can imagine how popular I became as my entire hall was somewhat chilly compared to the rest of the building.

Had I known about this, I could have said “I’m doing this for your health, so you’re welcome!”

Tuba says September 9, 2016

I loathe cold showers and being cold (so much so I intentionally moved south as a young man.) If cold showers daily added 20% to my life span I wouldn’t so it. Hate, Hate, Hate them… (and yes gene that turns on the brown fat burning function poorly in me. I have always despised the cold.)

tj says September 9, 2016

Hi Dennis big fan longtime reader and got all your books, love your site.

Sorry if this comment in wrong subject article.

Lifetime struggle with weight (lost 76 pounds, gained back 24 (now back in good mindset so lost 7 agian)
I can do ok on IF and one feeding a day suits the pig in me lol

My question is though, I have started doing bodyweight morning workout. As im fasted and not eating till much later, am I doing any damage to my body

I know its not optimum for gains etc but it suits my schedule/mood/motivation
Just worried if its doing more harm than good

Thankyou for taking time to read. I have looked for answer on othet websites. But I trust you most

Thank you

    P. D. Mangan says September 10, 2016

    Hi tj, thanks for all the kind words. I think your schedule sounds fine and you’re doing vastly more good than harm. If you were lifting heavy and to failure, I’d advise you to eat around workouts – but you’re not – you’re doing bodyweight exercise and your main goal is fat loss. A fasted bodyweight workout and not eating until later should be good for both fat loss and your health, your mitochondria will be in fine form.

      tj says September 10, 2016

      Thankyou for reply, you are making a positive change in this world.
      Cant ask for more than that

ConantheContrarian says September 13, 2016

Would cold exposure count if I am exercising in the cold? Would the heat produced from the exercise nullify the benefits, e.g., it is 45 degrees F, and I am doing sprints, and my body is heating up from the exercise. What happens?

    P. D. Mangan says September 13, 2016

    Conan, I think that would be correct. Your body would have to feel the cold strongly to get the effect. For instance, if you swam hard in a 45 degree pool, the heat of the exercise is more than offset by the cold water.

7 Beneficios De Ducharse Con Agua Fría (Y Como Hacerlo) - El Hombre Superior says September 16, 2016

[…] igual que el entrenamiento de resistencia, la exposición prolongada al frío está asociada a una menor resistencia a la insulina (mayor […]

RT says October 14, 2016

Hi PD,

If I remember correctly, on your twitter page you shared an excerpt from a very old book/article about insulin/diabetes/insulin resistance. IIRC you shared it with tednaiman or jasonfung on twitter. I remember reading the article and finding it interesting, but cannot locate it again.
If I am not mistaken and if it rings a bell for you, could you give me a link or article name?

Durandel Almiras says November 23, 2016

Mangan, I was looking back in your archives for something along this line. Have you heard or yourself experienced better mental clarity from cold weather? I swear I have more energy, better mental clarity, less physical and mental fatigue, better overall mood, and better focus in cold weather. As a Floridian, I’m very interested if these effects are due to the weather and not rather a psychological effect born of my love of 40-60 degree weather that comes about down here now and again.

    P. D. Mangan says November 23, 2016

    Yes, definitely.

Steven Mitchell says January 11, 2018

What are your thoughts on the practice in (Eastern) Europe where they sweat in banyas/saunas then dip in freezing water or roll in the snow? Is going from one extreme to another a healthy practice? This is a long standing tradition and I enjoy doing it when I’m in that part of the world. Harder to do it in Australia!

    P. D. Mangan says January 11, 2018

    While both saunas and cold exposure have health benefits, I’m not sure if going from one extreme to the other does.

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