I was proud to be chosen as a presenter for the 2012 Ancestral Health Symposium, held in conjunction with the Harvard Food Law Society in Cambridge, MA.
Here’s the long-awaited video of my presentation, “What Is Hunger, and Why Are We Hungry?” It’s information-dense and moves very quickly, so I recommend that you put on your thinking cap and get comfortable. (Note that it ends at about 17:30…the rest is Q&A.)
Here are direct links to the videos: Vimeo version, Youtube version. Please go there and drop a “Like”—and a comment, if you’re so inclined.
My bibliography, including linked references, can be found here.
Thanks are due to Sam Osterling, and the Harvard A/V team, for the finished video.
What’s In It, And Why Should I Watch It?
As I state in the abstract: “People aren’t obese because they enjoy being obese, and diets don’t fail because people dislike being slim and healthy. Diets fail because hunger overrides our other motivations.” Therefore, we cannot possibly understand obesity and the metabolic syndrome if we don’t understand hunger, and how it is modulated by nutrition and human metabolism.
Fortunately, the science of hunger is relatively well-established and well-understood. Unfortunately, it is not well-understood within the ancestral health community, nor within the community of nutrition research at large—which tends to treat hunger as an inevitable consequence of a healthy diet, or mires it in ad-hoc explanations clearly intended to justify a conclusion already reached, usually for political reasons.
Thus, the purpose of my presentation is to summarize and explain the current state of hunger research, so that you can use the framework it provides to inspire and organize your own research, and to address your own issues around hunger. It includes material from my ongoing article series “Why Are We Hungry?” as well as a great deal of new material, which I look forward to exploring in detail in future installments. I’m proud of it, and I hope you find it both interesting and valuable.
Meanwhile, please post your feedback and questions in the comments!
Live in freedom, live in beauty.
JS
As always, you can support my continued efforts to bring you good information, unbiased and uncluttered by advertising, by purchasing a copy of The Gnoll Credo or a T-shirt. Seriously: have you read the reviews lately?
[…] “What Is Hunger, and Why Are We Hungry?” – J. Stanton GNOLLS.ORG / Posted on: January 28, 2013GNOLLS.ORG – I was proud to be chosen as a presenter for the 2012 Ancestral Health Symposium, held in […]
At last I’ve been waiting for this for ages!
very nice, well done mate
That was great. I was actually thinking about Seth Roberts as you were speaking, because his Shangri-La Diet was a huge help in my weight loss. Once I experienced the appetite suppression provided, I was able to make real choices about food- so, my diet migrated to low-carb paleo, with a firm emphasis on nutrient density. Anyway, Stephan Guyenet has claimed the Shangri-La Diet as proving out his hyperpalatability ideas, but I think this requires a simplification of the theory Seth Roberts came up with. It would be interesting to hear your ideas on why the Shangri-La diet works. From what you said in the talk, I assume it must be increasing satiety in some way.
i enjoyed the video very much, thanks! DEFINITELY lived up to expectations, after reading your outstanding series on the subject!
I’m going to go take my multivitamin right now! (I’m usually kind of “meh” about them, but now believe I better get on it!) This was so interesting to me- great job! While I eat a very clean evolutionary diet- I amaze people at the amount I eat and have a very hard time stopping before feeling stuffed. It make sense that perhaps I’m just trying to get enough nutrients in my diet(if I understood you correctly). The food I make also tastes REALLY good so that makes it hard to stop as well.
Hahah been waiting for this ever since reading Guyenette’s summary of the AHS speakers and lambasting you, I knew then it would be worth watching LOL
J, as a writer you face the same issues I do as a project facilitator and I am glad you take the same approach to address them.
Terminology is EVERYTHING and with incorrect terminology we are stifled and cannot advance in the proper context.
Great lecture, got 6 minutes left so am going back to it 😛
Great talk ..well worth the wait.
I think you make some excellent points about satiety ..my question is ..there are some foodlike substances which I can eat lots of..white chocolate with coconut chips ..the whole block is gone if I get the chance..never do I get that full feeling or satisfied so it just goes down..but my brain and common sense screams for me to stop because my motivation to stay slim and not pork out on trash food is over-riding the urge to slam dunk the confection.
So failure to stop eating has a huge mental or cognitive component. Did your research have much to say about the role of will power to overcome these kind of urges. ??
Neal:
I appreciate the vote of confidence! I spent weeks putting it together — and that doesn't count the months of research that went into Why Are We Hungry?
August:
First, the Shangri-La Diet (and all of Dr. Roberts' research) long predates any of Stephan's work, and Stephan was clearly familiar with it — as evidenced by the fact that he cites the very same studies Dr. Roberts does in SLD. Second, I agree that Dr. Roberts' work is far more sophisticated than “You ate too much tasty food, it broke your hypothalamus (or whatever this month's retroactive ad hoc explanation is), and you got fat” — a non-explanation we can trivially discard based on the observed demographics of obesity in America, which was the point I made right at the beginning of the talk.
In contrast, I see some interesting evidence in support of Dr. Roberts' work on flavor-calorie associations, and the SLD can indeed be explained in terms of the four hunger drives and two modulating factors.
tess:
Thank you! I look forward to exploring the topics from my talk in more detail.
Lisa:
I'm not a huge fan of multivitamins, because they tend to contain a lot of “micronutrients” in artificial forms that may not have the same health benefits as natural forms, and may indeed be toxic to some extent (e.g. folate). I tend to agree with the Jaminets' analysis and recommendations in Perfect Health Diet, with the caveat that I'm not sure multi-milligram doses of iodine are necessary or beneficial for everyone.
Meanwhile, are you unhappy with your body composition, or just surprised at your ability to dispose of calories?
Danny:
A sound theoretical framework — including consistent terminology — is absolutely crucial to both scientific and engineering progress. I shake my head every time I see arguments about whether a particular food is “palatable” or “rewarding”…the sloppy conflation of distinct biological phenomena into a single concept, erroneously called “reward” and attributed to food instead of to our perception of it, has trapped thousands of people in a dead-end from which they cannot possibly understand hunger, obesity, the metabolic syndrome, or anything else.
It's even worse because the science I cite is not new, obscure, or particularly difficult…there's simply no excuse for not presenting it properly.
Cyclops:
Satiety is primarily nutritionally driven. How much essential nutrition is there in white chocolate with coconut chips? Let's see…mostly sugar and cocoa butter, with a little bit of milk solids…
So, like most other desserts, it's a source of fat and sugar calories, and little else. Consequently, it won't produce satiety, and it's a very bad idea to eat it any time you're hungry, because it won't satisfy your hunger. Yes, there's a reason that I proscribe snacking in “Eat Like A Predator“!
In contrast, no one has to tell us to stop eating steak: it's self-limiting, because our bodies have a sound idea of how much complete protein is required and desired. In fact, it's very difficult to overeat any minimally processed foods: we generally have to start adding lots of purified oils or sugars — which, again, generally have most of the nutrients purified out of them.
I didn't talk about willpower much in the presentation, because I didn't have time! However, I discussed it at some length in Part III.
JS
great job. thanks.
you were very hyper. (i always imagined you’d be like yoda ^_^
cheers,
cannot WAIT to get home and see this video!
got the email this morning but was up late so had no time to watch it, have some other videos to catch up on too (primalmeded is also on the list)
Thank you for saying that no one *wants to be* obese.
Thank you for saying it with sincerity.
That was great, my favorite presentation so far. The talk and your series on hunger explains why I don’t crave junk food anymore. Eating a SAD I loved cookies, chips and doughnuts. Two years ago I didn’t think I could ever give up grains and sugar but now they do not tempt me at all. Like you explain the palatability of the food didn’t change, I changed.
I’ll second all the positive comments here – great talk, about a rarely talked about subject. The fact that you have Seth Roberts intrigued is a good sign!
The notion that “we change” not the food, is great, as is the fact that, with a little effort, we can change so that we know not to eat the junk foods, and why.
One of the foundation;s of Paul Jaminet’s Perfect health Diet is that it should be both satiating *and* tasty. A diet that is lacking one or both elements will not be followed for long. Many low fat diets suffer this problem, with their followers always being “hungry” and then feeling “guilty” when eating any really nourishing (i.e. fatty) food.
The lack of satiety many obese people feel is evidence that many (most?) are malnourished. But because most people (and doctors) can’t separate the concepts of nutrition from calories, this conclusion is rarely reached, nor the condition corrected.
pam:
I'm not sure it's possible to write these articles for so long, for free, without being enthusiastic about the topic!
eddie:
Let me know what you think.
E Craig:
It's very easy to fall into that particular cognitive trap, especially if you've never been obese.
Glen:
Exactly! The more nutritionally replete and metabolically functional you are, the less hedonic impact junk food will have. And since our brains don't have instinctive knowledge of the nutrient content of every possible food, I think it's plausible that it takes some time for them to associate whole, unprocessed, nutrient-dense foods with increased satiation and satiety.
Paul N:
I was able to converse at length with Dr. Roberts the next day at AHS. He's sharp, and very data-driven: I think the fact that I didn't claim to know what causes obesity impressed him the most.
Also, I absolutely agree with Dr. Jaminet that nourishing food should also be tasty food. I harbor some hope that my work has influenced him to be more explicit in that regard, both on his website and in the new edition of the PHD.
“The lack of satiety many obese people feel is evidence that many (most?) are malnourished.” Absolutely, and it supports my contention that obesity is primarily a failure of satiety — whether due to a malnourishing “heart-healthy” diet, internal metabolic dysfunction, or (most likely) a combination of both.
JS
I got involved with Transcendental Meditation when I was 21, and for the thirty years since then, I’ve always had a focus on eating a “healthy” diet. Unfortunately, the new-age dietary dogmas I had embraced were not a good fit for my physiology, and as I hit my late 30’s, I started to pack on the flab. I started shifting toward paleo 9 years ago, and I am now highly attuned to how different foods affect me. I can now see and differentiate the different types of hunger, and it very much resonates with what you say on your video.
I don’t have great blood glucose control, and the worst hunger is that voracious gnawing hunger from starch-induced blood sugar spike. I can also look back and recognize the nutrient hunger I would get from calorically sufficient but nutritionally deficient vegetarian food. I don’t eat red meat every day, but the deep sense of satiety I get from 8oz of pastured beef or lamb is unmatched by any other food, even other animal proteins.
Thank you, I really enjoyed that .. Very interesting and enlightening.
(you also seemed whimsical & approachable (fun) to me. i meant thess in a good way! XD.)
one thing unclear to me: “hedonic value” can explain why we overeat some addictive food. this i agree.
since the satiety can’t be fooled, the body will still compensate it by eating less (e.g., twinkie/chips/etc) & having more of _real_ food in the next meal(s)? yes?
but Dr. SG does not seem to think so, so hence rewarding/addictive food = overeat = fat in the long run.
i also agree w/ Jaminet that nourishing, healthy food should taste good & satisfying/”rewarding”, (not bland).
the definition of “rewarding food” by FRH is bit wacky in my opinion.
cause i consider a food “rewarding” when it gives satisfaction.
last night i made butter squash soup (broth is made w/ grass fed beef bone + seaweed). (PJ’s recipe) that was mightily “rewarding” (to me) only took 1 bowl to make me feel “fed”.
this vs. instant raman soup (MSG induced unami taste) = NOT “rewarding” (in my book). yet it’s more addictive.
regards,
ps. the food of lowest reward has to be liver (for me). i can only have (tolerate) about 2 oz @ a time. sorry about being long & incoherent.
Alex:
You're correct: hunger isn't monolithic. It's completely possible to be hungry for some foods but not others, depending on your own nutritional and metabolic state (your state of satiety), and you gave two good examples.
I think this explains the insatiable cravings that low-fat and vegetarian dieters often have for cheese — their diets are deficient in saturated fat, often deficient in complete protein, and definitely deficient in the fat-soluble nutrients. I know that my own cheese cravings basically disappeared after a few months eating paleo…I was getting plenty of those nutrients from fatty meats and other foods.
And I'm with you on the red meat…chicken and pork just don't satiate like beef does.
Colette:
Thank you! Feel free to spread it via your favorite social media.
pam:
The fundamental issue is this: food does not have an intrinsic property called “reward” or “palatability”. As I emphasize in the presentation, hedonic impact (to use the correct term) is a subjective property which depends on our own nutritional and metabolic state, and our cultural context. If we try to assign this property to the food itself, we've made a cognitive error from which we can never recover. This is why FRH can't answer simple questions like:
* Why does food taste so much better when we're hungry than when we're full?
* Why do different cultures find such radically different foods delicious or disgusting?
* Why do I binge on foods I don't even like very much (e.g. stale Wheat Thins), but never binge on foods I find delicious (e.g. prime rib)?
As I explain in the presentation, hedonic impact (colloquially known as “palatability”) is just one of the four components of hunger — and it's primarily a product of the other three. Yes, people eat more of foods they perceive as “palatable”…but, again, our perception of “palatability” is a subjective function of our own nutritional and metabolic state, and our cultural context. It's a second- or third-order effect. Seriously: did food suddenly become tasty in 1980? No, it didn't…in fact, I contend that the low-fat whole-grain diet foods we're told to eat are much less tasty than the foods they replace!
Furthermore, if satiety is functioning correctly, eating more at one meal generally gets compensated for by eating less at subsequent meals. (As I pointed out with the food court study example, linked in the bibliography.)
Again: it is impossible to understand hunger, obesity, or anything else if we persist in thinking of “reward” as a property of food.
To return to your examples: Your butter squash soup is very tasty (it has high hedonic impact), but it's also very nutritious. Thus, it quickly produces satiation, which causes you to want it less and less (its incentive salience goes down) until you stop eating. Then, the satiety it produces leaves you feeling “full”, i.e. not wanting more food, for some time.
In contrast, the instant ramen has hedonic impact, due to the salt, fat, and MSG…but since its not nutritious, it does not produce much satiation or satiety, and you're still hungry after eating it.
Also recall from the presentation that the satiety response triggers a reward response by itself, independent of any sense of taste! So as you continue to eat nourishing food, your body associates the reward of satiety with the nourishing food you ate, and you begin to “like” it more (the taste accumulates hedonic impact).
A familiar example to everyone is beer: it's a bitter taste that we only begin to find pleasurable once it becomes associated with the alcohol intoxication which results from repeated ingestion.
JS
I think Youtube is dramatically better than vimeo.
Glad to see your talk and wish AHS12 would just release the remaining videos. AHS13 will be here before they are through with AHS12
Talk about the slow pace of evolution
Hi, JS,
thanks for taking the time to elaborate. beer is a good example.
it seems to me the both you & Dr. SG have no disagreement that some food makes us overeat. well, we’re all aware of it.
however, you trust the body more that it would compensate in the long term. he does not seem to think so.
by the same token, if satiety can’t be fooled forever, it would be interesting to learn the long term success success of a (mostly) mono-food diet, e.g., bland potato, bland liquid diet.
cheers,
ps. sorry me again.
i agree that “rewarding” & “palatability” are not intrinsic value of a food. & “rewarding” is particularly obsfucating (to me).
sort of like the wave function in QM (incomplete & not self contained)
cheers,
I have to say that I liked your series on hunger much better than the video, but I’m an information junky, and a short presentation just can’t contain as much as a series of articles. It was still a well-done presentation, but I just have my biases. 🙂
It’s amazing how much our food preferences can change over time on an individual level. When I was a kid, I hated dark chocolate, and now my favorite stuff is 90% dark. My sister and I hated broccoli, but now there’s practically a fight at Christmas dinner over the last portion. I thought visible fat was gross-feeling/tasting, but at lunch today I happily munched on several pieces of slow-roasted beef fat that were hanging out with the muscle meat. If anything, this shows how decidedly non-intrinsic the “palatability” of food is.
I’ll second the cheese thing. When I was vegetarian, I ate loads of cheese. Now with plenty of meat and fat back in my diet, I hardly eat any. I have found, however, that while I don’t crave cheese if it’s not around, I will quickly make a block of cheddar disappear if it’s in the house no matter how well-fed I am. Old habits die hard.
great video, as above commenter stated not as good as the series but you only had 20 mins.
very energetic and easy going speaker, came across well.
i think someone seeing the video would need to know some background before they “get it” though.
i cannot see how anyone with knowledge in the area (such as obtained through reading your blog for example) could not get the points you are raising.
Re: Meanwhile, are you unhappy with your body composition, or just surprised at your ability to dispose of calories?
Well, I keep thinking that after eating so well (zero grains, no beans, very little fruit & super quality protein, veg and fat) for 16+ months I would look like a fitness model… not the case 😉
I’m guessing from all my primal/paleo reading that I’m still just consuming too many calories even though they are the nutrient dense and not empty kind. I just plain love to eat and have got the food reward thing going on.
I loved the video and your work- thank you for being there for us!
Well Lisa,
Weight loss is hardly liner and the body always strives for a homeostasis.
I think that *my mental* ideal shape/size is probably lower than my formerly morbidly obese body's set point.
I don't know your situation Lisa, but maybe it's similar. I can gain muscle pretty good 'for a girl', but I've still got a fine thick layer of fat on it. If it doesn't resolve itself in time via sane exercise frequency and sane eating, I'm just going to say that I'm saving up for the famine and live with it.
Chuck:
I believe the issue is that they're depending on Harvard student volunteers to edit the videos together…but I could be wrong.
pam:
I believe the research is clear: failure to achieve satiety is the primary driver of hunger, and therefore the primary driver of obesity. The problem isn't that food suddenly became tasty or “rewarding” in 1980: it clearly did not, and any hypothesis that depends on such a non-fact is intrinsically bankrupt.
The facts point me towards this conclusion: the primary problem is that people are eating more and more non-nutritious foods that leave us malnourished and hungry, due primarily to the demonization of cholesterol and saturated fat, and to the replacement of nourishing foods like eggs and beef with a massive increase in the consumption of low-fat packaged and processed non-foods.
As we've seen, food has greater hedonic impact (colloquially known as “palatability”) to a hungry person than a sated person. So yes, palatability drives consumption to some degree — but hunger drives palatability. Concentrating on taste as the driver of consumption is like thinking that you can make a car accelerate by moving the speedometer needle: it's an effect, not a cause.
You might be interested in the prelude to the hunger series, Why Snack Food Is Addictive. Executive summary: taste without nutrition.
Beowulf:
I look forward to writing more articles that explore the subjects from my presentation in detail.
And yes, perception of “palatability” can change radically over time, which is another strike against the idea that food has an intrinsic property called “reward” that drives consumption. Those are great examples!
eddie:
There's a lot of fog in the air. “Food reward” is one of those seductively simple concepts that turns out to not just be wrong — like phlogiston, it actively impedes our understanding of what's really happening.
Lisa, E Craig:
Without knowing what you're eating right now and how much weight you've already lost, I can't possibly give useful advice.
However, I find that snacking is a typical culprit…especially snacking on nuts, which are generally high in omega-6 (which disrupts hunger signaling) and very calorie-dense. Nut flours are even worse.
Sometimes it's worth simply eating a bit more slowly…if your food is so delicious, why not savor it a bit longer? You'll probably find yourself eating less as a result.
Also, it is often the case that the formerly obese can never achieve fitness-model bodyfat levels without some amount of surgery…their hormonal environment is simply different than someone who never had 100 extra pounds to lose. ItsTheWooo talks about that at length on her blog, in between the rants.
Thanks, everyone, for your support and comments! Please spread this anywhere you see people getting stuck in the naive model, i.e. debates over “What food is more rewarding?”
JS
@J.Stanton
There may be other reasons for hunger besides reward etc. as in my case. I did a year- long dietary trial, during which the caloric intake varied from 1800 to 3400 and then down to 2100Kcal. I did not feel hungry at the low end but did not feel strong and at the high end I struggled to get that many Kals per day and did not gain much weight. On completion of the trial I ate “at libitum” and gradually my intake has levelled to about 1800-1900 and regulates itself without my conscious attention. Now, 13 months later, some days I have little hunger and eat only 1 meal. Prior to beginning my experiments my intake was about 2200-2300 Kcal (estimated). My problem was (and still is to some extent) connective tissue infection, not weight. Perhaps the extra energy was going to the immune system or to microbes. I also found that I could not gage (I tried first guessing weights) calories even roughly without weighing portions and recording daily. For that reason I tend to be skeptical about energy claims. I learned useful things by keeping careful records
Morris:
That's a great example. It's tempting to talk about “setpoints” and leave the discussion there — but as I've said before, “A 'setpoint' is just a homeostasis we don't understand.” The trillions of cells in our bodies each have metabolic requirements for macro- and micro-nutrients, as well as a functional hormonal environment (the “milieu interieur”).
Likewise, failing to satisfy some of those metabolic requirements may lead to a metabolic slowdown, or it may lead to hunger, or both. And satisfying them in excess may lead to increased fat storage, to increased muscle building and protein synthesis, to increased heat production, or all three. (And I haven't listed nearly all of the possible outcomes!)
Yes, it's a complicated problem — which is why there is no one cause of, or solution to, obesity.
JS
J. Stanton said:
I appreciate it, but too few people think and use the information already available! I won't be that girl. =)
Hi, JS,
my understanding is: a food becomes “rewarding”, or “hyper -palatable” not because what it has, but because what it does NOT have (lack of nutrients we need hence never satisfies the hunger).
this reminds me of the explanation of “original sin” by a theologian. he defined it as “lack of perfection” (something like that)
it does make sense to me. i.e., in other words, original sin does not exist; it’s like the empty sector left after one slice is taken eaten. (FYI: i’m not a believer)
A : a set (food stuff)
when ~A has no nutritional value. A becomes rewarding.
where,
~, ! : binary not operator
but ~A notsubset A
sorry, but it’s fun.
regards,
Wow. Just wow.
I don’t have any qualifications for this observation, but I suspect that it may take several years (at least) for some obese or other metabolically damaged people to even begin to re-train those trillions of cells to react to a new/nutritionally sound food stream. After all, every one of those cells had to adjust to and survive in an unnatural and inadequate nutritional state for years. This is certainly a tribute to our human ability to adapt and survive in incredibly harsh environments. Might not our bodies need years, not months, to reverse or modify what kept them going (albeit badly)for all those years? Just because we cannot see instant results does not mean nothing is happening.
A small example, not in the category of obesity, but surprising to me: About four years ago, I lost a great deal of my hair quite suddenly. It was a thyroid issue, but the hair did not grow back even after a couple of years. Got used to it, got a wig. I read Perfect Health Diet and nosed around this and other paleo sites and began taking selenium and iodine carefully (start low and go slow) as well as eating paleo. Nothing happened, or so I thought. Then about nine months after starting this regimen, my hair grew back suddenly, all at once, completely. Who woulda thought!
Thanks, JS. I have had to watch the video several times because it is so information dense. I do hope you continue the series.
And, Pam, your comment that what food hasn’t, as opposed to what it has, was great. I suspect that it will be a gateway understanding for people who cannot quite get their head around some of the science:D
@Otherworld,
your experience w/ hair loss is interesting. my hair was getting thin & brittle when i was diagnose w/ mild (subclinical) hypothyroidism. (probably due to combination of work stress + hormonal issue).
my hair has grown back some but not completely.
now your story gives me hope that the hair would come back fully.
theology can be fun; the logic is so convoluted & wacky.
i wonder some theologians were closet non-believers.
pam:
You are correct that what a food doesn't contain is a greater determinant of consumption than what it does contain. However, that still doesn't make the food itself “rewarding”, or less so.
First, because “reward” is a mashing together of two distinct phenomena: hedonic impact (“palatability”) and incentive salience (our “want” for more).
More importantly, because the lack of nutrition doesn't usually make a food taste better! What the lack of nutrition does is remove a food's ability to produce satiation and satiety.
Let's return to the classic prime rib vs. Pringles example: prime rib tastes better (it has more hedonic impact) than Pringles. However, the prime rib contains lots of complete protein, saturated and monounsaturated fats, fat-soluble vitamins, and other nutrients…and complete protein, in particular, is a strong driver of satiation (and, in the future, satiety). Therefore, we stop eating the prime rib at some point.
In contrast, Pringles are made of nutrient-free refined “vegetable oil” (mostly linoleic acid, for which our bodies have essentially zero use), and a little bit of potato slurry, which is mostly empty starch calories. They contain a negligible amount of complete protein, and almost nothing in the way of necessary nutrients. (Also, linoleic acid somewhat disrupts hunger signaling by itself.) Result: no matter how many Pringles you eat, your body will not get the nutrition it needs to get you through the day — and the Pringles do not satiate you (or produce satiety).
This is why “food reward” is a useless and misleading concept: in order to explain consumption of (for example) Pringles over prime rib, we have to posit that Pringles have a magical property called “reward” that makes us eat them to excess — even when we don't like them as much as other foods!
In contrast, the real science of hunger lets us understand that Pringles indeed have less hedonic impact than prime rib. However, because they don't contain the nutrients we need to live, they produce far less satiation (and subsequent satiety), which is why we have such difficulty putting down the tube.
Hedonic impact can help explain why we start eating a food — but the determinant of consumption is when we stop eating, which is determined by satiation and our current state of satiety.
And the primary reason that foods don't produce satiation and satiety is because of what they don't contain (as you correctly infer), rather than what they do.
Otherworld:
Fascinating!
Hair is an interesting case: it grows on a multi-year cycle, and the follicle has to hit the appropriate phase of its life cycle before new hair can grow. So I suspect a combination of factors: a threshold effect, where your thyroid status had to normalize sufficiently before hair was able to grow again, and the hair itself having to reach the growth phase.
pam:
I suspect there were a lot of non-believers in the Church during medieval times, since (in Europe) it was the only place where reading and writing were taught. If you were smart, it was basically your only career choice AFAIK.
JS
sorry, me again.
i think it is more than “what is lacking in nutrients” that makes a food “rewarding”.
e.g., leafy greens have nutritional values but not enough protein. they’re in want.
but no one can overeat plain leafy green, unless they’re covered by fat & seasoned.
some additional factors have to make a food unsatisfying , rewarding & hyper-palatable.
(unsatisfying yet rewarding & hyper-palatable is pretty funny to describe a food, in my opinion)
regards,
pam:
You're still stuck with the naive model as your mental framework.
Here's an analogy: it's not possible to create any of the primary colors (red, green, blue) by the additive mixing of any number of other colors. No matter how many other colors of light you mix together, you will never produce red light.
Similarly, it's not possible to define or describe precisely defined first-order causes (hedonic impact, incentive salience, satiation, satiety) in terms of imprecisely-defined second-order effects (“rewarding”, “hyper-palatable”). No matter how you swizzle these imprecise, second-order terms around, you will never produce a definition of how hunger works. Consequently, you'll never understand it.
What you need to do is understand the four basic motivations (hedonic impact, incentive salience, satiation, satiety) — and then define these second-order effects (“unsatisfying, yet rewarding and hyperpalatable”) in terms of the four basic motivations.
It's unfortunate that others have confused this issue so deeply by failing to start with well-understood, uncontroversial basic research and terminology. As I'm sure I've said before, my intent is not to propose Bold New Hypotheses: I view the existing body of well-established science as perfectly adequate to explain observed phenomena, and my intent is to bring that science to my readers as best I can.
Back to your example: greens don't have much hedonic impact by themselves (they're “unpalatable”) because they contain essentially zero calories — and we need macronutrients (protein, fat, carbohydrate) as well as micronutrients. Furthermore, plants generally contain some quantity of anti-nutrients (e.g. polyphenols), which perhaps have hormetic benefit at low doses, but become frankly toxic at higher doses. There's a reason that we often find a small amount of bitterness to be tasty and piquant, but a large amount to be disgusting.
Furthermore, we require some quantity of fat to absorb fat-soluble nutrients, which is most likely why we find fats and oils on vegetables so tasty!
Again, “rewarding” is a meaningless term by itself, because it's a mashing together of the subjective properties of hedonic impact and incentive salience. If we find a food “rewarding”, it's because it has some quantity of hedonic impact (enough to make us start eating it) but produces very little satiation or satiety (so there's very little to make us stop eating it). And as I explain in the speech, availability modulates the end result.
So we can explain the “binging on stale Wheat Thins” phenomenon this way:
Stale Wheat Thins have very little hedonic impact.
But, since they're a packaged food and the box is already open (which is why it's stale), they are far more available than an omelet, which requires getting out the frying pan, heating it up, cooking eggs, chopping vegetables, cleaning up, etc. In contrast, all we have to do in order to eat the Wheat Thins is open the pantry and grab the box.
The problem is this: once we start eating the stale Wheat Thins, it's difficult to stop…because if we are hungry enough that stale Wheat Thins have any hedonic impact at all (remember: hedonic impact is a subjective property based on our current state of satiation and satiety), stale Wheat Thins are not going to satisfy our hunger! Since they're basically a bunch of empty carbohydrate calories, linoleic acid, and a tiny bit of incomplete, poorly digestible protein, they produce almost zero satiation or satiety.
Then, since the availability of an open box of Wheat Thins in our hand is maximum, it's easy to keep eating them even when their hedonic impact is nearly zero (their incentive salience is still enough to keep us eating) — and since they produce almost zero satiation or satiety, there's nothing to stop us from eating them except the empty box.
JS
that wheat thins explanation is great Stanton.
not that i know what they are, i assume they are an american processed food, possibly cereal?
on primalmeded i found a link to mr palatable’s blog and read his response to your speech. i seem to recall (read it a year ago mind) that he suggested your speech seemed confused and jumped around a lot, to the point you did not seem to understand the point you were trying to make yourself.
having now seen your speech i can call this statement to question, not sure how anyone with any knowledge in the field (even mine mostly obtained from blogs and some papers over the last 7 years) can say that.
seems $$$’s talk rather well though
“Seriously: have you read the reviews lately?”
this is at the end of the post.
i just read them now and they are great, i actually recommend your book to friends whenever they mention needing a new book to read.
i just bill it as a fantasy book as i don’t want to ruin it for them.
With respect to this hunger/palatability/FR stuff, for me, J’s presentation is crystal clear and a perfect description of the types of hunger I’ve experienced. Whereas, Stephan’s perspective doesn’t speak to me at all; I find it nebulous and incomprehensible. I still enjoy his blog, but I don’t think it’s as good as it was a few years ago, before he got his PhD.
eddie:
I was surprised that Stephan chose to attack me so directly, including a few gratuitious ad hominems…but as the video wasn't available, I didn't feel it was productive to respond at the time. I believe my presentation of the science (including the bibliography) is the strongest response to such attacks.
Yes, “Wheat Thins” are an oily, salty American snack cracker that comes loose in boxes, as if it were cereal.
I greatly appreciate your efforts to spread The Gnoll Credo! Telling Gryka's story is the reason I created this site in the first place…note that it's called gnolls.org, not “yetanotherpaleoblog.com”.
Alex:
Thank you.
There's no secret to why my presentation makes more sense: I didn't begin my research with a pre-existing hypothesis I hoped to prove.
Instead, I decided to read as much of the recent literature I could in an effort to understand the modern theoretical and biochemical basis of hunger, whatever that might be. I found, to my surprise, that there was extensive existing literature on the functioning of the reward system, and on how it applied specifically to our perception of hunger.
Result: I've been able to summarize the science of hunger in a clear and understandable way.
(In contrast, trying to force the facts to fit one's own preconceived notions generally results in “explanations” that are some combination of nebulous, circular, self-contradictory, or protean.)
I'm glad you find my work useful! Please spread it whenever it's appropriate (e.g. people arguing over whether a food is “palatable” or “rewarding”).
JS
Great stuff , Mr. Stanton. Having less and less time to read I lost track of your hunger series of blog posts. The 20 minutes …. well 45 would have been better … but the 20 minutes was SOLID and I applaud you for putting in the effort to do it so well.
I see now why the FRH is a fallacy and will be chasing it’s own tail. However, I really bet if you hung out with some of the *educated* proponents of that theory then y’all could really learn from eachother. It’s a great topic, and shouldn’t distract us from getting our loved ones off of margarine and bagels, which we all ultimately want even if we subscribe to a flawed model.
best,
jesse
J, this is excellent. I’ve been on again/off again the “paleo” train because I was suffering from too much information about what to eat. The devolution to bread, pizza, and chips is only a short slide for me whenever I think “just this one time.”
After I saw your video something clicked in my head – my food definitely was not satisfying me on a deep, biological, metabolic level. Somewhere in my brain I knew this was the case, from some biology or nutrition course I took long ago. It was when you pointed out the data on women who lost weight when given vitamin supplements versus those who did not receive supplementation.
I know you don’t generally recommend supplementation, and most in the Paleo crowd also don’t, but I started to stay on top of taking my daily multi and a few other supplements (iron, mg, D3) and started to notice I felt better after a few days. I also went low-carb and the one-two punch of supplementation + better food has helped me immensely.
Thanks for this terrific piece. THIS is the kind of stuff I need to be reading/hearing and sharing, not agonizing over the safe starch quotient of my diet (for me, I fear, there is none, at least not at the moment).
Hi J
That experiment with rats, micronutrients and sucrose is very interesting. One point: you say twice in your talk that their diet was a whole food diet. It was emphatically not a whole food diet. All the carbohydrate was refined. No wonder the micronutrient supplementation worked.
You also say obese people have iron and zinc deficiencies. Changes in blood iron and zinc in obesity are arguably caused by chronic inflammation, not deficiencies.
I’m sorry to sound negative. I think you talk a lot of sense about satiety, especially the micronutrient part. I have been trying to tell Stephan Guyenet about the role of micronutrients in obesity for years.
Jane: Couldn't the chronic inflammation cause those deficiencies by depleting those nutrients?
I have a half-formed comment/question that I want to get on the table while it’s fresh in my mind. It seems that any model about hunger would have to account for energy balance. Would you agree that the bodies first order of business would be to ingest enough food to meet energy balance needs and that micronutrients, while obviously vital, would be a second order concern?
jesse:
I already have! Seth Roberts' “Shangri-La Diet” is a much more sophisticated exploration of the reward system as applied to food consumption. Again, it's not the entire story by a long shot — but he's found an interesting piece of it. And as I said above, it's explainable in terms of the four basic motivations.
Amy:
I'm not a fan of most multivitamins, which usually give you a lot of things you maybe shouldn't have too much of (e.g. folic acid, manganese) and neglect things you're most likely deficient in (e.g. copper). However, even “Eat Like A Predator” recommends D3, a bit of fish oil, and (now) magnesium. If you want to be more comprehensive, the Jaminets' list at Perfect Health Diet is solid. I'm not anti-supplement, I'm pro-getting nutrition from food…but there are some micronutrients that our modern food environment makes difficult or impossible to get.
I'm glad you've found success, and I'm glad I was able to help in some way! Do stick around: I try to keep gnolls.org free of gratuitous arguments.
Jane:
The diet was a fairly solid approximation of the Standard American Diet of the era. Yes, it included white flour and some sugar, but it also contained meat, eggs, fruits, vegetables, and other real vitamin-containing foods — in contrast to the research diets used in most rodent experiments these days, which are made entirely out of individual purified ingredients plus supplementation.
I agree that the rat study raises some very interesting questions, like “Which of the supplemented nutrients were making the difference?”
And while I'm pointing out that obese people tend to have many different nutritional deficiencies, I'm not attempting to explain them purely in terms of ingestion…or explain them at all! That's why I spent more time on the controlled interventions: I don't know which of those deficiencies might be a cause and which an effect (or a side effect).
In any case, it's clear that micronutrient status affects our perception of hunger. This is an important fact which bears further investigation!
Jen W:
I believe that's the argument being made.
jesse:
What do you mean by “energy balance?” Our bodies have different requirements for protein, fat, and carbohydrate, and they have differing requirements and uses for nutrients within each class (e.g. linoleic acid != lauric acid). A “calorie” of protein (and what kind of protein?) is not interchangeable with a “calorie” of glucose. See these articles by Jamie Scott for an in-depth exploration of the subject: Part I, Part II.
The obvious consequence is that we can be hungry, even while in a theoretical calorie surplus. For example, you can eat all the Skittles you want — but since they have no protein or other nutrients, you'll never feel satiated, and you'll still be hungry even though you've consumed far more “calories” than your body needs each day.
So it isn't a question of micro vs. macro…it's a question of “What capacity does our body have to store this particular nutrient?”
JS
Hi JenW
What happens in inflammation is that iron and zinc are withdrawn from the blood into the tissues. According to Weinberg, plasma iron goes down as part of the ‘iron withholding’ process whereby microorganisms and cancer cells are deprived of the iron they need for proliferation. I think zinc is supposed to go down for the same reason.
Hi J
Once again, you talk a lot of sense. However I would point out that manganese deficiency may be at least as important as copper deficiency. Have a look at this paper showing that iron-dependent Parkinsonism in rats can be completely prevented by manganese. Yes, prevented. You have probably heard that manganese CAUSES Parkinsonism. In very high doses, it can.
http://www.ncbi.nlm.nih.gov/pubmed/9681949
Hi J.
Thanks for the response. I’m sure my question/comment is more to get my head into the right context here. But I think this will clarify it for me, you wrote:
“For example, you can eat all the Skittles you want — but since they have no protein or other nutrients, you’ll never feel satiated, and you’ll still be hungry even though you’ve consumed far more “calories” than your body needs each day.”
Agreed. And I’d say the opposite is true as well, you could be in surplus on all micro AND macronutrients, but deficient in energy substrate. Hence the energy balance question. Just so that you don’t have to cover the same ground over and over I think you may see this as part of “why we start eating” and not why we don’t (or do) stop. We start eating because, hopefully, we need something from the food. I want to not ignore the fact that what we need from that food may just be the energy that it contains rather than the macro or micro nutrients.
I’m thinking of an analogy to get friends/family off the calories in/out model. So I’m trying to come up with the right wording for the following question:
If your car took 3 types of fuel, and instead of getting oil changes, new tires and brake pads, fluid flushing etc… it was able to extend the life of those items by applying different combinations of the 3 fuels. How many miles per gallon would it get?
🙂
jesse
Jane:
As the Jaminets are fond of pointing out, every nutrient has an optimal range. Below it, we have deficiency issues: above it, we have toxicity issues. So it's not surprising that a modern diet can produce both deficiency and toxicity, depending on the foods consumed — especially when so many foods are “fortified” with a small subset of vital nutrients, based on nothing but guesses of how much an person of average mass and physical activity might decide to consume in a day.
jesse:
I think you're confusing your terms. Macronutrients are defined as “nutrients we need macroscopic quantities of,” i.e. proteins, fats, carbohydrates — and (sometimes) minerals we need a lot of, like salt, potassium, calcium, and magnesium. So a need for “energy substrate” is by definition a need for macronutrients.
One analogy is: your can needs many different fluids to keep running. Gasoline, engine oil, transmission oil, power steering fluid, brake fluid, windshield washer fluid, etc. Your car consumes each of them at different rates, has a different capacity for storing each one, and they're not interconvertible…you can't say “Well, I need to change the engine oil, but all I have is power steering fluid, so I'll just put that in instead.”
Fortunately your body, unlike your car, has the ability to store calories it doesn’'t need as fat or glycogen, or burn them as heat…but, with a couple exceptions which are very limited in how much they can process (protein->carb, carb->fat) it can't convert them from one form to another. So a “calorie” is not a calorie. For instance, if your body needs protein, you'll still be hungry no matter how many “calories” worth of starch you feed it, because you can't convert starch into protein.
Add to that facts like: eating less (less calories in) slows your metabolism, so less calories in = less calories out, and we can see that the entire concept of “energy balance” is a dramatic oversimplification.
Returning to the car analogy, it's as if we said “Hey, I've put as many fluids into the car as have gone out of the car, why did it stop running? After all, the car is in fluid balance.” Answer: gasoline won't substitute for transmission oil, and wiper fluid won't substitute for brake fluid!
JS
J, have you heard about the new satiety hormone uroguanylin? It’s made in the gut and acts in the hypothalamus and in the midbrain dopaminergic reward system, and it probably also promotes lipolysis in adipose tissue. In other words, it looks like the holy grail of obesity research. I’ve asked Stephan Guyenet to write a post about it but I don’t think he’s interested. Perhaps you would like to do it instead? I don’t have a blog of my own.
http://www.nature.com/nrendo/journal/v8/n1/pdf/nrendo.2011.206.pdf?WT.ec_id=NRENDO-201201
The point is that uroguanylin works by activating the enzyme guanylate cyclase, which has a requirement for manganese or magnesium. It much prefers manganese.
Sorry, that link I gave doesn’t work. The title is
‘Uroguanylin – a new gut-derived weapon against obesity?’
Here’s an extract from the article about uroguanylin.
‘Thus, for over 20 years, guanylin and uroguanylin have been well-known key paracrine players in intestinal ion and water balance. Another piece to the already intricate puzzle of obesity has now been provided by Valentino et al.,2 who identify uroguanylin as a gut-derived satiety factor. The ground-breaking finding comes from the identification of uroguanylin as an endocrine signal with a physiological role in energy homeostasis, thereby expanding the gut–brain axis by an additional factor.
Uroguanylin, a 16-amino-acid hormone secreted by enterochromaffin cells in the duodenum and proximal small intestine, was shown to be released after nutrient ingestion.2 Both guanylin and uroguanylin are secreted as prohormones, which require enzymatic conversion to yield the active hormones that act as agonists of GC‑C. Lack of GC‑C decreased satiation, leading to an elevated body weight due to increased visceral and subcutaneous adiposity in both male and female mice.2 GC‑C knockout mice also exhibited impaired glucose tolerance with hyperglycemia and hyperinsulinemia, together with marked liver steatosis. No differences between GC‑C knockout and wild-type mice were observed in lipid absorption, distribution and clearance, as well as in energy mobilization and expenditure. Thus, obesity was attributable to increased food intake, independent of the type of dietary nutrients and caloric content.’
Thank you for a refreshingly logical explanation of hunger with the science to back it up!
I have known this intuitively for some time and see the positive results in my clients constantly. No more cravings/binging once we sort out their gut health concurrently with focusing on nutrient density.
I discovered this personally when I was sorting out my FODMAPs intolerance. I dropped a lot of veggies from my diet and started eating more liver/cheese/seafood/bone broth. My absorption improved and Voila! More nutrient density = less hunger (after a few months) = finally dropping those last 5 lbs.
Hi J.
I don’t feel I’ve been able to get my point acknowledge, though it seems simple and non-controversial. It seems possibly even trivial, yet a part of the whole picture that I don’t think should be ignored. Perhaps it’s the limits of text communication or perhaps I’m living in my own world. I’ll take one more stab at it because I think you have continued to refine your responses in a way that gives me a better toolset.
First: pointing out that a need for energy substrate is pretty much a need for macronutrients. By the same token that you ignore the inefficient conversions of various macronutrients into other macronutrients which are more suitable for fuel (glycogen, fatty acids, aminos), I can ignore the energy value of micronutrients (and even some of the macronutrients by the definition you used). In that, if they provide any energy it is negligible and not worth mentioning in a high level discussion.
Secondly: You have obliterated your point that we can have sufficient calories, and yet remain hungry due to needs for specific nutrients (macro/micro/nano, whichever). But haven’t conceded the point that you could be replete in all specific nutrient needs and yet still need less specific nutrients as substrate for your long mountain bike treks, or my weight lifting sessions and soccer matches. It seems that you want to lump that into a nutrient need, like “i need glycogen”, and I can kind of see that… but at the same time it seems like a purposeful aversion to addressing energy needs as a specific requirement. I wouldn’t blame you because any nod towards energy balance could be a slippery slope like you mentioned above with the “fluid balance” analogy. But we have to be careful how we choose our models. Admitting that simple energy needs (typically glucose or fat) could be the driver for food cravings can alleviate the angst someone may feel if they are trying to eat low-carb or reduced calorie and still have cravings. Many people end up in that situation when they go to a paleo diet which is devoid of tubers/starches/rice/grains/dairy and low in fruit and are trying to do athletic endeavors. People trying to gain muscle mass need a lot more calories than they need anything else. I won’t quote the source but I read a muscle-head analysis that it takes 35,000 calories to build a pound of muscle, independent of the fat, protein and glycogen needed for the actual structure of the muscle. So that is a pure energy need. I believe lumping certain nutrients into a category of “usable as energy substrate” is a reasonable thing to do. And then believing that we could crave those nutrients for exactly that reason is also reasonable.
I’m throwing the towel in here because it’s kind of just going back and forth. If this doesn’t clarify my point well enough then I’m OK with it not being settled, or even having it assumed settled from your perspective but not from mine. By the way, thanks for linking those articles by Jamie, I think he offers a good perspective on it. He does make a lot of assertions to build his case that I’m not sure are true. Of course I’m not sure they are not true either and I’m willing to believe that they are, just that they come across as assertive arguments that aren’t common knowledge and thus would require some references/backing in a more rigorous setting!
take care J!
jesse
Jane:
That's an interesting development (AFAIK uroguanylin was previously thought only to regulate fluid balance), but I don't know enough about its other interactions to write an article that gives my readers a useful takeaway. Otherwise I'm just saying “Hey, look at this new satiety hormone we found, add it to the list.” (along with CCK, PYY, GLP-1, etc.)
Also, I've fixed the part where my forum software munches URLs.
Sondra Rose:
I'm glad to hear of your success!
Nutrition seems to be at the base of the health pyramid: fixing nutrition isn't a guarantee that our other problems will be fixed, but it seems to be a necessary precondition, and it often accomplishes a great deal on its own.
jesse:
OK, I think I understand what you're saying now. Yes, the need for more energy substrate is absolutely a cause of hunger…and it's usually the primary driver! (Most people think it's the only driver.)
Furthermore, in metabolically functional animals (including people) this drive is generally in balance with actual energy needs. As I said in the speech and in my articles, “Any animal whose faulty perceptions and motivations caused it to become obese, emaciated, malnourished, or poisoned by excess would have been strongly selected against.”
What I'm addressing in my articles, and my speech, are the situations in which hunger is out of balance with energy needs. “I'm gaining fat, why am I still hungry all of the time?”
There are several reasons I don't like speaking in terms of “energy balance.”
First, as I think I hammered home above, “calories” aren't an interchangeable currency. As you note, for someone doing frequent, heavily glycolytic workouts, fat does not interchange for carbohydrate…so it's quite possible to be hungry for something that can replenish muscle glycogen even in a theoretical “calorie surplus”.
In contrast, a sedentary person who doesn't undergo glycolytic exercise has very little storage capacity for carbohydrate, so once their liver is replete, they'll be storing it in fat cells and revving up their metabolism to try and burn it off…and they'll generally be hungry again once this process completes, even though they're in “calorie surplus” and gaining weight. Such a person should be eating more fat, which is supplying most of their energy needs at rest and at low exercise intensities (e.g. walking), and which won't result in metabolic spikes, blood sugar spikes, and then, inappropriate hunger.
Second, our bodies work very hard to adapt themselves to existing conditions, including food intake. Eat insufficient salt and your body will conserve it: eat an excess and your body will excrete it. Eat less energy substrate in general, and your basal metabolic rate will probably drop, as will your desire to expend energy via exercise. Eat adequate calories but zero carbohydrate, and your RER will drop as your body adapts to greater availability of fat. And so on.
So yes, I agree that a requirement for energy substrate is the primary driver of hunger. However, that drive is modulated by micronutritional state…
…and “calories” are not a fully interchangeable currency that satisfies a fixed need for energy.
That being said, it's absolutely legitimate to make a judgment based on the state of the system at a specific time, e.g. “If you want to gain muscle mass, you need to consume enough energy substrate to synthesize the tissues as well as the amino acids and fats required to build them — which is more than you consume in order to maintain your current weight at your current activity level.”
I believe that's what you're saying, and I agree.
However, what that does NOT mean is that if you ingest 500 more “calories” per day, you'll magically gain X pounds of mass per week. Your body might rev up your BMR to burn it off as heat (“I feel really warm today”); it might store it as fat; or it might synthesize new muscle tissue, IF there is sufficient protein available, IF you're generating anabolic signals through resistance exercise and a sufficiency of the hundreds of other factors required. Etc.
And that is why it's counterproductive to think purely in terms of “calories”. There is no biological system that has, as its input, a “calorie”.
JS
Hi JS,
Appreciate the closure, well worded and thought provoking. Love the blog. This is somewhat of a wasted comment but it would have been rude not to thank you for the response 😛
jesse
Jesse:
I'm glad we were able to communicate an understanding. Thank you for the support…and if you find my work helpful, you can support it by picking up a copy of TGC, a T-shirt, or just buying some stuff through my Amazon link.
JS
Hi J,
Notice your conspicuously missing from the current list of names on this years AHS pre-program? Will you be in attendance?
James
James:
My presentation was accepted, and I confirmed that I'll attend, so I'm not sure why I'm not on the online program. I'll email them and ask.
JS
@JS
Awesome! Look forward to meeting you there.
I think the current program is preliminary and is being updated slowly. I had an email from Kamal Patel saying that a full program with abstracts would be available in April.
Per chance do we get a sneak preview of the title of your presentation?
James
James:
I've verified that I'm confirmed. They're updating the online program as they go, and I'll appear on it at some point. And I'll let the AHS reveal the topic, as my abstract is a far more articulate summary than anything I can say off the cuff!
JS
@JS
Looking forward to it!
James
woo glad to hear you’ll be presenting again.
hopefully they’ll publish it quicker this year!!
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