Hormesis: How Certain Kinds of Stress Can Actually Be Good for You

Why are certain things “good for us”? Why does lifting weights make us stronger? Why does running a mile on a regular basis improve our aerobic conditioning and allow us to improve our times? Why does skipping a meal every now and then increase insulin sensitivity, lower body fat, improve lipid numbers, and generally make us healthier? Why are plant polyphenols so consistently associated with health benefits?

The answer is hormesis. You see, back when Nietzsche said, “That which does not kill us makes us stronger,” he may not have been talking about the positive and beneficial physiological effects of exposing yourself to various stressors and toxins, but he could have been. All those things – the exercise, the fasting, the plant phytochemicals, plus more – stress our systems and force us to adapt to the imposed stress. Organisms, after all, like to maintain homeostasis, stability, and balance, and hormesis is ultimately about the push to maintain homeostasis in a changing environment. If the environment changes – say, because of a weight lifting session – the body must become stronger, healthier, better in order to maintain homeostasis and handle the situation next time it occurs. Best of all, you don’t just compensate for the stressor. You supercompensate. You get stronger/faster/healthier/more resistant to disease than you were before. Think of hormesis as your body “hedging its bet” and going a little above and beyond just to be safe.

Beginning with the discovery that administering small doses of poison stimulated the growth of yeast, researchers have found the hormetic response to be remarkably preserved across species lines. Fungi (PDF), bacteriainsectsplants and algae, and animals all show adaptive responses to stressors. To date, around 5600 “dose-response relationships satisfying evaluative criteria for hormesis” have been identified. Hormesis, it seems, is a fundamental part of being alive. What this means, of course, is that many things that we assume are good for us are actually “bad.” They are stressors that initially do “bad” things to our health in the short term but induce an adaptive response that improves our health in the long term. Here are some examples:

Exercise – If you were to run labs on a guy who had just lifted heavy things for an hour, doing full body compound movements with excellent form and intensity, and was dripping sweat, the numbers would look awful. Inflammatory markers would be elevated. Oxidative stress would be evident. Cortisol will likely be high. The muscles would be suffering from extensive microtrauma – tiny little tears amounting to physical damage. Subjectively, he’d be in pain, exhausted, sore, and generally unable to do much of anything except rest, sleep, eat, and drink. Provided he rests and eats and sleeps, however, the guy will get stronger and faster and fitter as a buffer against future stressors over the next few days. Those inflammatory markers? They’re ultimately a signal for his muscles to repair themselves and come back stronger than before. A single bout of exercise, then, is oxidatively stressful to the body, while regular exercise lowers the oxidative challenge. In other words, the stressor remains, but our ability to respond to it improves (PDF).

Calorie restriction/IF – Skipping meals, limiting calorie intake, and simply having less food than your body expects is a major stressor, but it’s a stressor that offers many health benefits. The lack of food doesn’t just promote leanness (and in the case of IF, lean mass retention), it also triggers autophagy (both neuronal and systemic) – the process by which cells clean themselves up and recycle all the unnecessary and dysfunctional junk that’s been accumulating within.

Plant phytochemicals – You know all those colorful plant pigments with an impressive track record on promoting good health? Evidence is accumulating that many of the polyphenols, phenolic acids, and other bioactive phytochemicals exert some of their health effects via hormesis. Instead of evolving expressly for the benefit of Whole Foods shoppers, phytochemicals exist to protect plants from oxidative stress and to ward off pests. That’s right: they are natural pesticides, plant toxins meant to keep bugs and other pests away. They won’t kill us, of course, but they will irritate us enough to induce a compensatory adaptive response at the cellular level that results in many of the benefits attributed to fruits and vegetables. If we were eating blueberries the size of Volkswagens we might not survive the anthocyanin overdose, but a handful or two appears to be perfectly safe and even healthful.

Cold water plunges – As I’ve mentioned before (though not using the “hormetic” word), cold water exposure can elicit an adaptive response. For example, although ice bathing was shown to increase oxidative stress markers in swimmers, the markers for endogenous antioxidant production also increased. Anti-tumor immunity also gets a hormetic boost from cold exposure.

Sunlight – Our tendency to tan in response to sunlight is a classic example of a hormetic response. The tan protects our skin from sun damage, reduces skin cancer, looks good, and indicates that we’ve generated vitamin D.

Radiation – Although most scientists assumed that ionizing radiation would adhere to the linear no threshold model (where even the smallest exposures to a toxin result in elevated risk of harm), there is growing evidence that low doses of radiation actually protect against cancer via hormesis.

We don’t know all of the mechanisms behind hormesis, but there is one likely candidate: NRF2.  NRF2 is a transcription factor that, once triggered, expresses a number of genes involved in antioxidant defense, detoxification, and cellular protection. Many of the stressors we’ve just discussed trigger NRF2, including exercise, calorie restriction, polyphenol consumption, radiation, and sunlight.

It should be emphasized that while a low or moderate dose often elicits a favorable response, the opposite is likely true of a high or protracted dose. Intermittent fasting can elicit major health benefits, improve lean mass retention, and boost fat burning; starvation will also cause major weight loss, but not in a good way. Twenty minutes of moderately strong sun gets you a mild tan and plenty of vitamin D; five hours of strong sun gets you a sunburn. During a single stressful life event, adrenaline and cortisol will increase and make you alert and hyperware of your surroundings; a year of chronic stress will wear you down and lead to adrenal fatigue. This is also why I talk about chronic cardio. The occasional acute bout of really tough endurance work is probably helpful to your fitness; it’s the chronic, constant, day-in, day-out endurance training that is not, that will break you down. Even NRF2 has a “dark side”; its over expression will increase the resistance of cancer cells to chemotherapy.

Well, what do you think, folks? Personally, I’ve always found the hormetic response a valuable tool for viewing and assessing the world and all its myriad stressors. We’re bound to run into some of them – maybe all of them, at some point – and it’s nice knowing that there’s a real, quantifiable physiological phenomenon that explains how the hard times we all endure may not be in vain and may in fact actually make us stronger, healthier, faster, fitter, and better. You can’t help but be a glass half-full type of person when you filter many of life’s crazy headaches through the concept of hormesis.

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TAGS:  hormesis

About the Author

Mark Sisson is the founder of Mark’s Daily Apple, godfather to the Primal food and lifestyle movement, and the New York Times bestselling author of The Keto Reset Diet. His latest book is Keto for Life, where he discusses how he combines the keto diet with a Primal lifestyle for optimal health and longevity. Mark is the author of numerous other books as well, including The Primal Blueprint, which was credited with turbocharging the growth of the primal/paleo movement back in 2009. After spending three decades researching and educating folks on why food is the key component to achieving and maintaining optimal wellness, Mark launched Primal Kitchen, a real-food company that creates Primal/paleo, keto, and Whole30-friendly kitchen staples.

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102 thoughts on “Hormesis: How Certain Kinds of Stress Can Actually Be Good for You”

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  1. I think the key is finding the balance between the benefit and overdoing it. I think we can all agree that intermittent fasting on day a week is beneficial but not eating for an entire week is bad, but where do you draw the line between good a bad. These days I do a 15 hour fast 5 to 6 days a week because I am trying to get as lean as possible and it is nice to get an extra 30 minutes of sleep in the morning. I don’t know if I am overdoing it but I would hope my body would tell me if I need to eat breakfast more often. This morning I was planning on fasting but at 9:30 I got really hungry so I grabbed breakfast. I think people just need to experiment until the find the right balance that makes them feel better.

  2. I’d like to know more about how this kind of thing ties into the level of total stress.

    Here’s my situation: over the summer, I was doing ice baths, IF and some of the other things described here with good results, but then classes started on top of three jobs, a breakup, a move and a death in the family, and suddenly even the smaller things (delaying breakfast for 4 hours or so) seemed too much to deal with, so I stopped.

    Here’s the question: should I have stopped? Was what my brain telling me true – that is, would these small, low-level stressors sum with the other bigger ones and make life even harder? Or would keeping those habits (and the stress involved with them) have had enough benefit to outweigh the discomfort and downsides and help me deal with the other stress better?

    1. Wow, tough hand you were dealt. I think you’re right to not add to your stress. From my experience, the thing to do was take care of self–sleep, eat well, try to minimize worry and grief, meditate (for me it was tai chi). When I put too much physical stress on top of the emotional, I started getting sick, getting back trouble, etc. Best wishes…

      1. Agreed with you here. I would have stuck with the basics like sleep and eating well. Something I do to mediate is just relax in bed with no distractions for 15-30 minutes. Not before bed, but during the day at some point.

        1. How do you keep from falling asleep? I’ve tried that a few times when I’ve got a (rare) hour free during the day, and I always doze off. It seems like I’m getting enough hours of sleep at night, although there’s always the possibility that it’s not very good sleep (streetlights outside my window and kittens knocking things over in the wee hours…)

      2. Thanks, Tom! The break-up and move were/are super stressful, but both about getting away from bad situations, so things are getting consistently better. I’ve never tried Tai Chi but I’m getting back into a lot of other martial arts, all of which have a strong slow-the-hell-down-and-relax component. It’s working 🙂

        1. Forget about so called “martial arts” – get a class learning how to do Pa Tuan Tsin/or Chin, Google that & do some research on Geoff Pikes The Power of Ch’I. I did 30 years ago, and it changed my life around. Also go for a meditation class as that works well too. I’m 54 but easily pass for mid 30’s, easily!!!

          See Geoff Pike Video

        2. Don’t worry if you fall asleep.

          I follow qigong and try to spend some time each day just stopping and letting my body be; lying flat somewhere quiet. The qigong state is very rejeuventating, even 10 minutes, and if you fall asleep that’s what you need; just set an alarm if necessary.

          Taiji is just a form of qigong, all amounts to the same, allowing your body to be and let the qi flow and heal and balance.

    2. Sorry to hear about everything your dealing with. I would also add getting outside to the list of helpful things that you may want to focus on. Its not going to end your grief or solve any the issues your exerperiencing but my time spent outdoors has a huge affect on my ability to manage stress. It’s more than just the sun but the idea that I’m connected to something grander.

      1. Yes. Another reason the summer was so awesome (despite working the aforementioned 3 jobs) was that I had at least one full day every week spent entirely outside, immersed in the fabulosity that is Durham, NC’s Eno River State Park. Usually literally immersed in the river. It’s been a while since I’ve had enough time to go somewhere lovely outside and just be. Now that we’ve got more morning sunshine, it’s probably a great time to pick that up again! And “connected to something grander” is a fantastic way of putting it 🙂

    3. yes, I believe your brain (and body) was telling you to moderate total stress levels. There is an element of triage, but also of ensuring adequate rest and recovery time from total stressors. the rest and recovery time only occurs during parasympathetic states (especially sleep). so, for example, if you go from an intense workout to a socially stressful interaction, neither is getting you the parasympathetic recovery time you need.

      chronic maintenance of a sympathetic “performance” state will lead to atrophy. it is the alternation between sympathetic performance and parasympathetic rest and recovery that enables the hormetic adaptation of various complex systems, including the body as a whole and specific subsystems within the body (eg cognitive/nervous, musculoskeletal, cardiovascular, immunological, digestive, etc). All need hormesis, and all in balance with one another. Chronic stressing (and/or atrophy) of one will adversely impact the others due to their interdependence. We see this sort of dynamic in relationships between people, and in societies as a whole (eg ref. the spirit level, the wealthiest members of a society suffer from reduced quality of life when the poorest members of society suffer from chronic stressors).

      1. also, if you fall asleep when you meditate, it is because you need the sleep!

  3. Could you write a full post on autophagy? I’d like to know how it works and what it takes to turn it on. I wonder at what point in a fast it kicks into high gear?

    1. If you haven’t already, you could take a look at Mark’s fasting series. The subject “autophagy” and how it works was explained pretty well in some of them.

  4. ok, ill play devils advocate. so why do we avoid grains if the body has this mechanism?

    Certainly we all know someone that’s lived beyond 90 and ate bread daily (both my grandpas for example). Obviously there’s other factors at play.

    But who’s to say the body cant overcome the harm that grains cause?

    1. That’s a good question, Chris. While I’m not an expert, here’s my answer. Those of us who were grain eaters did so virtually at every meal, every day. So we were constantly putting stressors on our body with no let up. I think in the end, while we can certainly survive eating that way, it is much more difficult to thrive that way.

      1. That’s what I was thinking. And even if someone can adapt to grains without autoimmune issues, eating them every meal would be akin to chronic cardio. So even those who ‘tolerate’ them would be best to reduce the volume.

        Just wanted people to think beyond just following what Mark says!

    2. The best you can do when developing a diet is to figure out the foods that the greatest number of people will thrive on, and then let the individual customize their diet based on their own tolerances. Very few people are allergic to meat and animal fats, but up to 30% of the world’s population are sensitive to wheat. Beyond that, the grains people typically eat just aren’t that healthy for them. They are highly processed, highly convenient (which allows for overeating like Dano says), likely made from months or years old flour (which lowers nutrient content and increases rancid fat content), are mostly useful as a source of carbohydrates (which are best eaten if you are starving or need to replenish glycogen stores), and other reasons I can’t think of at the moment. You as an individual might actually feel better and be healthier eating high quality, freshly milled grains than you would be without them, but saying “gang, lets not eat grains” is good, general advice for a populace that is sedentary, lazy, and overweight.

      1. guys i understand the premise of the primal methods.

        but the premise of hormesis contradicts it.

        I wanted people to challenge the rational discrepancy, not just recite new age anti-wheat theories to me.

        1. But the new age anti-grain theories are what make grains special. Now, I could see someone sensitive to grains eating small dosages of the offending grain to increase their tolerance to that grain and possibly confer some other health benefits, but I doubt that there is any scientific literature regarding dosage or other possible health benefits (the studies are going to be based on either no grains or lots of grains), so it would be difficult for Mark or any other paleo-guru to make recommendations. If a person isn’t sensitive, then I’m not even sure there’s anything there to cause a hormetic response, so the grains just become another source of carbs.

  5. Thanks, Mark.

    I have been very skeptical of the push, not just at Whole Foods but everywhere, to cram in as many antioxidants as possible. After all, they are poisons.

    My approach is to eat (and live) as much as possible like my great (great, great, etc.) grandparents, e.g. “Eat your veggies,” which would have been a daily serving or two of fresh, local, organic ones. Not “Stuff your face with kale because it has the highest load of antioxidants.”

    (In the forums as Hedonist2)

  6. I like this post because I was just having a discussion regarding something very similar. So my question is:

    What about gluten? What about WGA? What about all the lectins in legumes? What about mycotoxin in corn?

    Could small levels of these toxins be healthy as well? In my own experience, I feel better eating 90/10 and giving myself some occasional exposure to SAD foods as a “treat” because if I eat cleanly for too long, I seem to become intolerant to the foods and crash hard if I eat a meal I didn’t control 100%. Could periodic, occasional exposure to wheat, soy and corn actually have health benefits, similar to exposure to low levels of bacteria strengthens our immune system? Maybe the treshold for gluten toxicity is just lower and we have to cycle it less often to see the health benefits?

    I wonder people’s take on this.

    1. i’d like to know the response to this as well. about 6 months into eating Primally, i started having major digestive issues that i’m still dealing with to this day (8 months later). it started after a trip to North Carolina where i had very little control over how my food was being cooked since i had to eat out nearly every day. now, i can’t seem to eat anything that i didn’t make myself, and even a lot of things i DID make myself, without having some kind of reaction. would it be a good idea to “cycle in” some bad stuff just occasionally?

      1. Yes, Mark, give us your thoughts on this! It seems that a day per week eating oxidized and trans fat, artificial sweeteners, grains, and high sugar will actually make people healthier.

  7. “The occasional acute bout of really tough endurance work is probably helpful to your fitness; it’s the chronic, constant, day-in, day-out endurance training that is not, that will break you down.”

    This quote actually excites me the most out of everything stated, mostly because I have one day/week of 45 min-1 hr endurance training (that was yesterday). I wasn’t sure if I was overdoing it based on PBF.

  8. I guess it all comes down to dosage then… Finding the minimum effective dose of stressful activities is important, or, for the overzealous out there, the maximum non-harmful dose.

  9. So far everything that I have tried from this list backfired for me.
    I tried IF, and I ended up binging.
    I tried cold water showers and ended up being afraid of exposure to water for a while. Even now I have to run hot water for a while before I dare dip into the shower. It also gave me aversion to swimming for a few weeks (pool felt too cold).
    I tried running sprints, and I quit running outdoors because I started to dread running.

    1. You likely have aerobic deficiency syndrome. Part of this is a intolerance for carbohydrates, which unfortunately generaly leads to cravings for sweets. Take long walks, or easy cardio at 50-60% of your max Heart rate. Be easy for 3-6 months and then bring sprints and weight training back

      1. Oh, crap. I about dismissed your post with the ‘Not another unknown condition I had no clue about that I do not have’, and then I looked at the description, and I have every symptom on the list. I, uhm, I need to take it more seriously. I will rad about it and try to follow the guidelines, though it hurts to again let go of fruit and starches 3 days after I brought them back in. I guess, it explains why I felt the best when eating just meat and vegetables. Holy cow.

    1. Yes, I’ve written about and studied the hormetic response, and always felt that was a hole in the literature. Would a person who smokes one cigarette daily have better lung function than a non-smoker?

  10. Sigh, are we really going to say that the positive benefits of stressors justify eating like a cow (grains) or say smoking. Mark’s article is pretty clear on how this works. And Leida, IF doesn’t make you binge, and cold water doesn’t make you afraid of water, and sprinting doesn’t make you fear running. All of these are uncomfortable (which is your body’s way of recognizing stress), I love crossfit and PB fitness except fr the few minutes a day when I’m actually doing it lol. Its the price we pay for health and vitality and its not even that steep a price.

    1. Cows don’t eat grains unless humans force them too. And enjoying a cigar likely has some positive effects as well as negative. It’s about balance. Smoking a pack of chemically laced cigarettes habitually is not enjoying anything and is addiction, certainly negative.

    2. Lifting makes me uncomfortable, but I enjoy it & come back for more. When I do not IF I do not binge. Normally I am out of bed the second I woke up, but when I was doing cold showers, I found myself hiding in the bed. Exposure to the heat (steam room) is just as stressful and not exactly comfortable, but I run to the steam room every chance I get.

  11. Doing a cold water plunge would possibly kill me.

    I have cold urticaria. Google it folks. It’s fascinating stuff!

    1. Todd, I was thinking you live up north somewhere, like Michigan…? You ever think about moving south?

    2. Hey Man,
      My daughter has the same thing. People think we’re crazy when we tell them she’s allergic to the cold.
      I feel for you.
      Hopefully, we’ll be able to move south eventually.

  12. Security doesn’t come from what you have , It comes from what you can handle.

    Perhaps after 2 million year our bodies expect a few bumps on the road.

  13. I think if I saw a blueberry the size of a Volkswagen, the happiness would kill me faster than the anthocyanin overdose.

  14. There may be another role of plant polyphenols – insects are high-carb feeders, that chew through carbs to get at protein. A good way for a plant to protect itself is to decrease insect’s fertility and growth by modulating their hormonal response to carbohydrates; thus plant polyphenols that boost insulin sensitivity and lower blood sugar (e.g. cinnamon, curcumin) control insect predators by making it harder for hungry insects to eat and process enough food to obtain protein for growth. And polyphenols that are antibiotic suppress the gut bacteria that feeding insects need to digest cellulose. e.g., https://kops.ub.uni-konstanz.de/bitstream/handle/urn:nbn:de:bsz:352-opus-48638/8_Walenciak_etal_2002_Gut_bacteria_MS_Acentria.pdf?sequence=1

  15. Mark you forgot to mention sleep restriction as way of applying hormesis in case of insomnia.

  16. I did a cold water plunge yesterday. It may have been the coldest water I was ever in. I could only stand to be in for about a minute. Within a few seconds of swimming the back of my neck tightened up and I felt a strange mixture of calmness and being frantic. I assume my vagus nerve was stimulated, which is apparently a good thing. I felt calm after, sort of sleepy, and surprisingly not that shaky after getting out of the water.

    1. And I was barely even buzzed this time. I think the hormesis is working.

  17. I think some fear is healthy. The elation and terror I feel when I’m precariously perched at the top of a tree or catching my grip after a branch has just snapped is a satisfying emotional brew.

  18. I agree that humans evolved to deal with stress. Primitive humans faced intense stress every day that they were alive, yet today people get stressed when the cat sneezes. Why is this so? In my opinion it’s because of our modern diet.

    Excessive fructose from sugar and HFCS and high glycemic carbohydrates mainly from grains can over time trigger a form of food-induced brain dysfunction called Carbohydrate Reversible Brain syndrome or CARB syndrome. People with CARB syndrome don’t handle stress very well because their hypothalamic pituitary endocrine axis is not working as intended.

  19. Mark, I am a big fan of your work and your website, but I hope you won’t mind my playing devil’s advocate here. I am not convinced of the beneficial value of plant toxins. The more I read about plants and health, the more it seems to me that hormesis is simply an (unproven) theory invoked to try to explain this apparent paradox: plant chemicals are toxic and can kill healthy cells as well as cancer cells, and even cause cancer in laboratory studies, yet epidemiological studies of people who eat more vegetables tell us that veggies are good for us. Epidemiological studies are, as we all know, pretty shaky ground to stand on. Given that a number of cultures throughout history have thrived beautifully without any veggies at all, isn’t it possible that the less veggies we eat the better off we are? The best study available which supports this alternative theory is this one by Young et al: “Green tea extract only affects markers of oxidative status postprandially: lasting antioxidant effect of flavonoid-free diet.” Br J Nutr. 2002 Apr;87(4):343-55. In this study, a diet nearly devoid of vegetables provided the best antioxidant protection. I haven’t been able to find a single study supporting the health benefits of vegetables. I’m just sayin’…

    1. Reading your site had me scared of vegetables but then I remembered people can live on a vegetarian or vegan diet. Granted vegetarians and vegans are probably eating more plant foods than just vegetables.

    2. If exposing ourselves to stressors were to be “always bad” and hormesis was a bunk theory, then how would humans have evolved? It takes exposure to stressors for the body to say “maybe this isn’t so good for me” and to begin to adapt to tollerate it as a protective measure. And bingo, beneficial effect from being exposed to stressors. Not always the most rapid transformation, but if we didn’t expose ourselves to these things, we wouldn’t adapt or evolve at all.

    3. Define “any vegetables at all?” I agree that many cultures eat far fewer plant-based foods than we tend to, and many eat a very plant-based diet.

      But even the Inuit (the poster culture for the “carnivore” argument) went to great lengths to find and eat plant-based foods, even though they did (and still do?) get most of their energy from animal fats. Hardly a “no plants” diet, though. Likewise, cultures from the tropics traditionally ate a more plant-based diet than anyone, and still went to great lengths to incorporate animal products (e.g., meats and seafoods).

      I am not aware of any example of any traditional culture that eats “only animal” OR “only veggies.” It has always been some omnivorous mix. I would love to hear about traditional cultural examples of pure animal-based or plant-based diets, if anyone has any.

      We need to put an end to dietary ideology and talk about what it means to be a nutrivore. Hormesis is far from unproven, it is a phenomenon inherent to complex systems and, as far as we know, a LAW of life. Different people are situated at various places on a hormetic spectrum for various reasons of health and/or context, but that doesn’t mean that what works for them at that point in time will work as well for them in the future, nor is it generalizable to other contexts.

      I strongly recommend anyone interested in this check out Fred Provenza’s work on behavioral ecology (check out his book Nourishment).

  20. Great article, Mark. Have you checked out Todd Becker’s blog, “Getting Stronger” at getting stronger.org? It’s an entire website dedicated to the practical application of hormesis. He goes in for many of the practices you advocate — cold showers, intermittent fasting, phytochemicals, etc. But he seems to differ from you in shunning even supplements like Vitamin C or Vitamin D. Do you have a response?

  21. I overtrained for years. I recently hurt my shoulder and was unable to continue weight training and crosssfit at the levels I was doing.

    Keeping to a paleo diet and just walking and resting most of the time, I have leaned up to a nice 187 lbs, the lowest I have ever been (at 6’5 {196cm})

    Mark makes some great points about IF and hormone response in regards to overtraining.

  22. I spent almost 5 years tripping on DXM and cannabis, tobacco, with lots of sugar and a bit of alcohol. I just got bloodowork done in the hospital and everything was described as “great” and the nurses sounded enthusiastic. I presume that I owe my stable health to the primal diet.

  23. Hormesis can magnify or destroy, just like any other life or self inflicted stressor, because health is a daily practice, coupled with simplicity and significance.

  24. Wow, absolutley wonderful article Mark! I enjoyed it so much!
    I thought IF (done with some vegetables, wild blueberries, raw cocoa nibs and coconut oil to introduce a nutritional ketosis), were amplifying autoghapy which is wonderful, but at the same time stressing the body in á endokrinology perspective by lowering T3 to T4 thyroid, being low in body circulation and important trace minerals, abscent in regulating nervous tensions in the central nervoussystem etc.) I thought that if you are feeling hunger on IF (as an marker for cortisol to rise – “starvation is about to happen soon, cortisol might just say”), this can accumulate a negative hormesis but now i know…

    Now i know that fasting is healthy if done short term, and that it actually comes with an hormesis effect, if it was not done to euphoria/prolonged experienced.
    Thank you so much Mark for widering my abbillity to follow hormesis on a healthier level and gaing all the benefits!

    Kind regards, Marco / student of 22 years of age in Sweden.

  25. I just want to say that I find the discussion in these comments really thoughtful, insightful, uplifting, and restorative of my faith in humanity.