If you’d like to take a look at a critical review of her other work on this topic, I’d highly recommend this damning analysis of her “Big Fat Surprise” book: https://thescienceofnutrition.wordpress.com/2014/08/10/the-b...
At least in the United States, the nutrition science of the last 100 years has overseen the most incredible deterioration of metabolic health in human history. There are some folks doing good work out there, as there always have been, but listening to mainstream nutrition science as if their word is law is akin to letting the inmates run the asylum.
Reduced fat is an interesting one. If you actually look at what Keys was investigating all the way back in the mid 20th century, the hypothesis was always that saturated fat increased CVD risk. The translation of that into policy and marketing aimed at total fat cannot be placed entirely at the feet of mainstream nutrition science.
As to the claims that sugar is addictive, this is unsupported - sugar does not meet the DSM-V criteria for addictive substances based on current evidence (https://link.springer.com/chapter/10.1007/978-1-4899-8077-9_...)
As for added sugar - again, you’re labelling policy decisions as nutrition science. The DGs that I’m aware of recommend as little added sugar as possible, but when you’re making policy you have to strike a balance between strict enough to make a difference, but not so restrictive that no one listens. That’s different from what mainstream nutrition science would claim (which is indeed that there are no benefits to added sugar and several risks).
The same point applies to your claim that nutrition science has a role in getting people to adhere to satiating diets. No, nutrition science is to help us understand what those diets might look like. It is not responsible for getting populations to adhere to them.
This is false, in the 90s when I grew up there was no such criterion, and the posters of the pyramid prominently depicted sliced white bread.
The worst part of the food pyramid was the indication to use all fats and oils sparingly. There's never been any point in which the evidence suggested that olive oil or other monounsaturated fats should be avoided
Citation please or I'm calling extreme bullshit. Everything I've ever read has argued for putting more nutrient dense fruits and vegetables as the basis for a healthy diet.
More importantly, I think the nutrition community was woefully naive to the point of being negligent when they tried to defend the food pyramid. One quote I heard was "When we were recommending lower far intake, we never imagined Snackwells." Well, why TF not??? It should have been blatantly obvious that by demonizing fat and making people feel like carbs were "free" that companies would react appropriately and come up with fat-free, sugar-stuffed replacements that had a huge amount of calories, left you feeling unsatiated, and tasted like sweet cardboard. Probably even worse was frankenfood like Olestra.
I agree with the original point - while I think the field of nutrition science has improved a lot over the past decade, they have a ton to answer for and never did an appropriate "mea culpa" for all the great harm they caused.
pic from wikipedia named USDA pyramid 1995-2005: https://en.wikipedia.org/wiki/Food_pyramid_(nutrition)#/medi...
Even with that first sentence though, the base of that shitty food pyramid really just doesn't talk about "whole grains" - it calls it the "bread, cereal, rice and pasta" group, with a graphic that includes spaghetti, crackers, a baguette, a bowl of cereal, etc. And having lived through that time when the food pyramid was taught in school, they certainly weren't delineating between highly refined flours and things like oatmeal, brown rice, quinoa, etc.
looks like I agree with you on this part: https://news.ycombinator.com/item?id=41964513
As for whole grains vs fruit vs vegetables, here's a SR and MA of studies looking at different food groups and the RR of all cause mortality: https://www.sciencedirect.com/science/article/pii/S000291652...
Three servings of whole grains per day: 0.79 (21% reduction in ACM) Three servings of vegetables per day: 0.89 (11% reduction in ACM) Three servings of fruit per day: 0.90 (10% reduction in ACM)
So the evidence seems to support the suggestion that consumers should focus on whole grain consumption as a base for their diet.
Many, many people disagree with that. Most days I eat no grains at all and the rest of the time, I strictly limit my grain intake. For example, I just finished a meal where I used one tablespoonful (uncooked volume) of rice (boiled with some peas). (The meal also included meat and butter, the source of most of my calories.) White rice is the only grain I eat anymore, and I would never eat brown rice, which is loaded with oxalate and other phytotoxins. I added to this just-finished meal B vitamins in the form of pure refined powder (which I liberated from capsules).
It is very obvious from how it makes me feel that brown rice is bad for me.
The cultures that have eaten rice for thousands of years eat almost exclusively white rice. Brown rice was not even possible to make before the spread of tech for precision machining (which reached East Asia in the 1900s). You have to remove the hull from the rice before you can eat it, and before precision machining, removing the hull (traditionally done by pounding the rice with a log) also removed most of the bran and germ. Yes, some bran and some germ remained stuck to the rice -- so it was mostly-white rice, as opposed the polished, completely-white rice we have today with no bran and no germ at all. Still it had only a small fraction of the amount of bran and germ that modern brown rice has.
I've read that, too, many times, and I stopped believing it after I watched videos (on Youtube) of people preparing rice the traditional way. Particularly, I paid close attention to the color of the rice after the processing steps: it was white with bits of brown stuck to it.
I searched for bookmarks for those videos, but cannot find them.
(I don't know about wheat: I only investigated rice.)
https://youtu.be/qGNUPqHvTso?si=WWnY3OLALTBREVMs&t=525
I bookmarked another video, but it has been made private since I watched it.
Here is a very illuminating moment: the rice has already been pounded, then winnowed (the separated hulls removed), but there are still many kernels that need to be hulled (roughly one kernel in every 150 or 200 kernels), so the rice is put back in the mortar for another round of pounding. In other words, although there is more pounding to do to make the rice edible, already most of the bran is off the rice (and thrown away along with the hulls). (When only a few unhulled kernels remain, she removes them one by one with her fingers.) This supports my assertion that it is impossible with traditional methods to get the hulls off while leaving on most or even a significant fraction of the bran. Again: I think you need precision machines that only became available in Europe in the 1800s and in East Asia in the 1900s to get the hulls off (which I think you really need to do if you eat rice every day and want to keep your teeth) while leaving most of the bran on the kernel. I.e., people in traditional rice cultures did not have the ability to consume anywhere close to as much rice bran as is possible by eating modern brown rice.
Look at the dose response curve for wholegrain consumption in this bad boy (and yes, it’s looking at whole cereal grains, not including fruits and vegetables). Greater consumption associated with better outcomes: https://www.sciencedirect.com/science/article/pii/S000291652...
When I joined a Christian Health Sharing ministry, they determined that I needed remedial help, due to hypertension and dyslipidemia. They assigned me to monthly virtual meetings with a dietician. The dietician's advice horrified me, because it would've made me sicker, and exacerbated my conditions. I approached the ministry's administrators, requested a replacement dietician, and they replaced her alright. The new dietician had basically the same credentials and the same letters after her name, but she was way more flexible, listened to my reasoning, and supported my choices with encouragement.
My parents followed every "diet fad" in the 1970s-1980s, from 2% milk, to margarine, to yolk-less-egg-whites, to reducing red meat, to low-sodium everythings, to bottled fluoridated water. It was sheer torture and disgusting. My mother didn't know the first thing about flavor or pleasure in cooking, and never used the spices in her rack. Our food was always bland. For breakfast she'd slap down a jug of milk, a box of Chex, a bowl and a spoon, and abandon me to go do housework. I would sit there and read the mendacious lies known as "Nutrition Panel" on the side, and simply stewed in my resentment for the whole thing. It's a travesty.
Chex, I suppose it depends on whether it was wholegrain or not. Wholegrain cereal is associated with pretty good health benefits, refined not so much.
(And really, margarine can be plenty tasty. As a kid I actually preferred it to butter for some reason.)
https://youtu.be/reLIPoZQZ-8?si=lLXfhsdm89zlOWsI
Those commercials played multiple times a day in my childhood, and they never failed to piss me off, because they clearly demonstrated that "milk and a box of Chex" was not by any means a "balanced breakfast".
So why wouldn’t replacing butter with margarine be a positive step for one’s cardiovascular risk profile?
Surely that’s both a large enough cohort and a large enough effect size to change one’s diet?
https://www.sciencedirect.com/science/article/pii/S000291652...
It's almost as if all of these studies are looking at tiny effects that they can't adequately measure, and contradicting each other.
The other study I'm mentioning :
https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD...
If yes, do you believe it would be expected to see heterogenous outcomes in studies that don’t disambiguate whole grain and refined carbohydrates when replacing SFA?
If yes, then there’s clearly no contradiction in the above studies. If no for any of the above, I’d love to hear the argument.
Also, just as I was mentioning in other comments, I think there is a good chance this reduction of the problem to just whole grain - refined grain is unlikely to tell the full picture. I don't see a priori why eating whole wheat would be exactly as healthy/unhealthy as eating whole rice, or oats, or millet, or barley, or quinoa or any of the many other unrelated plants we call "grains". Maybe we should prefer certain grains and avoid others, regardless of the whole/refined distinction; this difference might also depend on genetic factors, with certain populations perhaps being better suited to certain grains than others. It is very much possible as well that certain grains are better eaten whole, and certain others better eaten refined, say if there are substances in certain husks that are problematic over long time or in certain quantities and so on.
And this is not even going into other factors, like rates of contamination of the grains with pesticides/fertilizers/naturally-occuring substances in certain soils; handling, washing, and preservation; cooking differences; and probably many others that I'm not even thinking of.
And while some of these effects will naturally lead to heterogenous outcomes in studies that don't control for them, this doesn't increase my confidence in those studies. The fact that there are an extreme number of possible confounding variables in everything to do with nutrition is basically why nutrition science is almost hopeless as an entire endeavour: we can only reliably find extremely strong effects ("lack of vitamin C causes scurvy"), and even then we need a bit of luck. The rest is built on a house of cards: every new medical or biological discovery tends to upend nutritional studies and what they control for.
We should also learn from history that replacing our diets based on "nutritional science" has generally been unlikely to yield good health results, as long as we're not already obese. For example, nutritional science kept recommending replacing SFA with any UFA, and ended up killing many, many people because it didn't know that trans unsaturated fatty acids are actually worse than SFAs for overall health.
We can reasonably expect that similar things will be discovered in the future about other parts of margarine, and that eating traditional foods with a long history of safe human consumption is a much safer path, be they olive oil or butter or lard.
As for nutrition science and its effect on health, just because one intervention had deleterious effects doesn’t mean that you can claim that the net effect of nutrition science on health has been net negative. Again, see no reason to believe that without actual evidence supporting it.
Nutrition science told us that we should start fortifying flour to prevent some horrendous diseases, and the net result of that has been far greater than the problems caused by trans fat consumption, for example.
I see no reason to believe that traditional foods are safer than novel foods. In fact, provided both are equally health promoting during the reproductive window, then it’s more likely that a given novel food is better for longevity than a traditional one.
As far as I know, the main mechanism for that is reduction of HDL-c. However, the study you cite found no reduction of HDL-C from TFA substitution.
> PUFA reduces LDL-c by a greater degree and there are no known issues like there are with TFA, so substituting SFA for PUFA seems like a no-brainer.
Key word being "known issues". One of the major issues with nutrition science is this grouping of vastly different foods based on a single simple category of substance. There are a lot of different PUFAs, and even more different specific oils or fat solids containing PUFAs, and there is no reason to believe that they are completely interchangeable in our nutrition. UFAs were once thought to be the same, before the important distinction between PUFAs and TFAs (and the still unclear position of non-TFA MUFAs) was discovered and recognized.
> As for nutrition science and its effect on health, just because one intervention had deleterious effects doesn’t mean that you can claim that the net effect of nutrition science on health has been net negative. Again, see no reason to believe that without actual evidence supporting it.
Yes, some basic findings in nutrition science did improve things worldwide health. The discovery of vitamins and various other micronutrients was by far the most important. The discovery of dietary fiber and its roles allowed nutrition science to course correct a number of bad recommendations from the earlier era. In very specialized fields, such as high performance athletes, it also show reproducible, predictable results (though not necessarily on long-term health, just measured by competition success).
> I see no reason to believe that traditional foods are safer than novel foods. In fact, provided both are equally health promoting during the reproductive window, then it’s more likely that a given novel food is better for longevity than a traditional one.
Traditional foods have an extremely long history behind them of not being acutely harmful to at least one particular population, with traditionally passed on limits of safe amounts of consumption and safe methods of preparation. They have been consumed by populations that lived with much reduced medical care than today, so they are known to be resilient even in the absence of medical interventions, which often confound nutritional studies, especially in older adults. They are also much more likely to be well adapted to the particular genetics of a certain population, unlike nutritional advice which is almost entirely "universal".
One of the main sources of nutritional discoveries has in fact been the study of traditional diets. From vitamins to fiber to fermented foods' effects on gut microbiota, the discovery has always come from trying to understand why a particular population is thriving nutritionally.
The main drawback of traditional foods is that the mechanism for passing down information on safe preparation and consumption was informal, and can be easily lost. They also tend to be hard to create industrially, so they are likely to be much harder or more expensive to consume compared to modern industrial food products. However, for people who can afford it, they are by far the better option compared to the uncertainty and contradictions of modern nutritional advice.
[Note: this is the same account as tsimiones, I'm not trying to hide behind some new name, it's just related to some software on my work PC]
Yes, there are no known issues. You can speculate that there might be, but we could equally speculate that they’re actually superfoods and we don’t know it yet. At the end of the day, speculation is all it is so I believe it’s most sensible to apply the principle of indifference and look only at what we do know. That is, margarine is a sensible replacement for butter on the current evidence.
Because of antagonistic pleiotropy, we can actually make an a priori argument that given two foods that are equally health promoting within the reproductive window (I.e. it’s not killing or neutering people before the age of ~50), then probability holds that the food to which we are least adapted is actually more likely to promote longevity than the ancestral food.
Because adaptations are on net more likely to be antagonistically pleiotropic than not, foods to which we are most adapted are more likely than not making a trade off in favour of reproductive success over longevity. Since we don’t have these adaptations to novel foods, this concern does not apply to them.
Therefore, given butter and margarine are both similar in their effects on reproductive success, with no further information at all we should favour margarine. The fact there are studies confirming this is just icing on the cake.
my humble research found that diffs in nutrition between whole grains and refined grains carbs is very small compared to say whole grain to some complex carbs from leaf veggies. The same goes to glycemic index, satiety index, etc.
(Maybe we should think of a word that means "carb that the human body can efficiently convert into glucose or fructose" and try to spread that new word. "Insulinogen"?)
yes, because they consists of 90%-95% of water, then if you cook them, water evaporates and you get some amount of carbs.
But leaf veggies is one side of spectrum, with refined carbs on another, there are bunch of stuff in between.
this is not my reading of that study.
This is exact example of junk science.
What differences in goals and methodologies have you identified that you believe renders them so different that they cannot be summated?
Not sure what you mean by “no indications how balanced and what components where in diets”, you’ll have to clarify.
Grains are cheap and energy dense, if your goal is to feed a large population it makes a lot of sense to put them at the base of the pyramid, that's what will keep you alive, as in, not starving. Higher up are fruits and vegetables, also cheap, they will provide with nutrients that you need to stay healthy on top of the calories that will keep you alive. Higher up are animal products, expensive but rich in proteins and a few other nutrients that are a bit lacking in the base layers, they help you get stronger and more performant in addition to healthy and alive. On top are pleasure foods, not really necessary for your body, but enjoyable.
I take it like a mirror of the "hierarchy of needs" pyramid rather than nutritional advice for people with effectively unlimited resources.
When I saw it in my local village's clinic it makes sense because it actually encourages eating some meat and fruit instead of none, which is the norm here because of poverty.
Policy and advocacy is deceptive, dishonest, and lacks nuance.
The recommendations regarding fat hasn't changed in 30 years in most countries. FDA recommended limiting saturated fat already in 1980 (didn't bother looking further) and has recommended not exceeding an energy intake from fat over 30% since at least 1990. 30%e from fat is not a low fat diet.
The guidelines from 1980 explicitly mentions reducing saturated fat and sugar.
I think the problem is that we haven't been listening.
The problem is that we have, unfortunately, been listening.
I am so tired of this crap. Energy intake increased by something like 400kcal/day since 1960. Mostly from processed foods.
At the same time physical activity plummeted.
What do you think is the most probable explanation of obesity: the above or that we halved our SFA intake?
1. Nothing to do with saturated fat.
2. Nothing to do with the dietary guidelines.
In fact, this kind of diet that is the basis of the modern dietary recommendations because we know it is associated with good outcomes.
I started following a Mediterranean style diet for my own heath a long time ago, and when I realized the harm of animal agriculture I stopped eating animal products completely. I of course would have preferred to continue eating like before, but evidence told me otherwise.
But every time I get a cold (with 3 kids in kindergarten and school, viruses are obligatory) it is seen as a weakness of my way of life. I even had a congenital condition blamed on my plant-based diet by more than one person, despite me doing a lot better than just about everyone else with that condition (which is probably just luck, my family have done well as well, while eating a standard diet).
> 3 kids in kindergarten and school
I see you have chosen the path of perpetual illness and insomnia.
This is the fallacy that makes pseudoscience thrive right now: The idea that the enemy of my enemy is my friend.
Wannabe influencers position themselves as the anti-establishment position. People who are frustrated with institutions blindly fall in line behind them.
The fallacy doesn’t stand up to even the simplest critical thinking, yet it triggers something subconsciously that leads far too many people to see a contrarian statement and assume it must be true.
Meanwhile, these people are grifting away, selling books and pitching Athletic Greens (or the latest sponsor of the day). This person is no exception.
All metrics I see show faith in these institutions going to zero. Most good science I see is making (and has been making for decades) a really strong case that this loss of faith is deserved.
Credentialism is collapsing under the weight of its own corruption.
Good institutions have mechanisms in place to correct themselves.
And most of the past failures of our institutions were discovered and corrected by ... the institutions (sometimes the very same institution or other institutions whose role was to counterweight the institution at fault)
Unfortunately the trap we all fell into is that we interpret this success at catching and fixing failures as proof that the institutions have failed and thus that they will never be trustworthy ever again.
We need to train ourselves that the trust we put in the institutions does not mean we trust everything that comes out of them, but we trust that the mistakes will be eventually corrected as they happen.
But that's not what's happening now. The society has equated the point-in-time failure of an institution with the failure of the entire process and also extended that feeling across the board towards areas of our society that haven't failed us much.
Nothing good will come out of that. For one, it will remove any incentive from future institutions to try to be objective and self-correct. If self-correction becomes a "capital sin" for institutions, they will be selected to favour absolute unquestionable truths which cannot possibly ever need a correction.
But also. it completely ignores the fact that most institutions are useful, even while they suffer from failures/corruption and that destroying them altogether is going to throw the baby out with the bathwater.
I want them to share their uncertainty, nuance, and reasoning. Anything less I view as well intended lies.
Institutions as a concept are critical. Some institutions are net negative. Blindly following and support all institutions because some or even most are useful is a fallacy of its own.
I think the nutritional institution credibility is bankrupt at the moment. given the importance, I am willing to take the risk and put in the work to find my own way in the Forrest.
Furthermore, most institutions can only provide heuristic advice, which even when true, is t always true, or true for everyone. It should never be treated as dogma
For what is worth I'm precisely trying to bring nuance to the discussion about institutions.
Institutions do fail. That's a normal mode of their operation. They fail all the time. When institutions fail, they fail and some other institution (in the broadest case the institution of civil society as a whole) calls them out for the bullshit.
The question is: what to do next.
Should we dismantle that institution and other similar institutions, including the ones that helped provide the data that proved the failed institution wrong just because they are all institutions and guilty of the original sin of being an institution?
I find this approach to be a little bit too extreme.
Yes. many institutions are full of shit. Let's reward people who can reign them back in. But we need professionals. We cannot all be experts in everything. I know it can feel this way because we have an unprecedented source of information at our fingertips but realistically we cannot all just figure out things on our own.
I sure feel I'm super smart and I can figure out everything if I just had a weekend but luckily I grew just wise enough to know foolish and misleading that feeling is.
I agree that folks should not condemn the messenger. In this context, that seems to mean science as an institution or individual scientists. The lying institutions should be disregard untill they are shown to actually be reformed.
If your doctor says your number one priority should be to lower inflammation or lower bad cholesterol, you should consider lowering the amount of red meat.
The issue is that of course we need protein. Older people who tend to lose muscle mass and are at risk of falling should actually increase protein intake and weight resistance exercises. If their stomach tolerates fish legumes nuts, wonderful. If they tolerate red meat better, then they should eat red meat. Like every thing else in life, there are trade offs and nothing is completely healthy or unhealthy.
Personally, I follow the advice of Dr Micheal Gregor, one of his most recent books has over 13,000 citations! Their team has read over 20,000 nutritional papers!! And he'll tell you that whole grains and beans are an excellent staple of a healthy diet.
And with regards to Saturated Fat and even dietary cholesterol, he said, to make a really long story short, that they're really bad for you. There's way too many specifics to list but his 500+ page book (How not to age, and How not to Die) goes into great details and backs it up with a ton of research.
The n3:n6 ratio was a hypothesis that never panned out. If you look at the studies that “support” it, the “bad ratio” is brought about by reducing n3 levels below sufficiency, not by keeping n3 levels at the RDA or higher and then boosting n6 further.
So it’s no more evidence that n6 is harmful than taking a cohort of people, reducing half of the group’s iron intake to a minuscule amount and claiming that because that group’s “iron:magnesium” ratio is wrong, then consuming more magnesium is clearly harmful. It just doesn’t add up.
I refer to the very readable review by Philip Calder “A systematic review of the effects of increasing arachidonic acid intake on PUFA status, metabolism and health-related outcomes in humans.” His final statement is that an increase in arachidonic acid intake up to 1.5 grams per day does not significantly change the parameters associated with inflammation, blood clotting or atherogenesis. In this very interesting observation, I was astonished by the fact that the background diet was not taken into account. Although the intake of arachidonic acid with the background diet is reported several times, the resulting metabolic consequences are not discussed.
From the data provided, it can be concluded that the background diet in all studies included in the review was a Western diet, the proportion of arachidonic acid being estimated at 200 to 400 mg per day. Our studies on healthy volunteers were carried out with formula diets and allowed a precisely defined supply of arachidonic acid over a period of 6 weeks. These studies have shown that the exclusion of arachidonic acid from the diet (vegan diet) causes a progressive decrease of this fatty acid from 11 + 3% of the total fatty acids in the cholesterol esters of the plasma to 8 + 2% after 6 weeks. The later studies on patients with rheumatoid arthritis have shown that an intake of arachidonic acid amounting to not more than 80 mg/day does not increase the concentration of arachidonic acid in the phospholipids of the plasma and in the erythrocyte lipids. From these findings I have concluded that the body's own production of arachidonic acid is around 80 mg per day. This means that the Western Diet provides approximately 2.5 to 5 times the estimated need for arachidonic acid.
This intake that is higher than the requirement primarily has no negative consequences. We know from many studies that the "silent inflammation" characteristic for the prevalent diseases of western societies has a latency period of more than 10 years before the consequences such as arteriosclerosis and myocardial infarction become apparent. The body is evidently able to avert the consequences of an unfavorable diet for a long time. To do this, there are numerous regulatory options, such as substrate or product inhibition in the case of enzymes or the inhibition of transport to or incorporation into cells. Arachidonic acid has a very special metabolic pathway that offers possibilities for regulating absorption from the intestine, transport in the chylomicrons, metabolism via the enzymes involved and also for incorporation into the cells. For example, we have found a completely different efficiency for the uptake of arachidonic acid into the cell membrane for platelets compared to erythrocytes or granulocytes. It is therefore very likely that regulation options on the metabolic pathway of arachidonic acid can, to a certain extent, compensate for changes in intake.
Only when too much arachidonic acid is present in the food for a prolonged time do these protective mechanisms apparently fail and inflammation and the manifestation of lifestyle diseases is seen. This explains the long latency period with which the diseases of civilization occur. It is documented in the literature that unhealthy supplementation, such as megadoses of vitamin E, has no deleterious effects on health-related outcomes for humans in the short term. Only long-term observations and meta-analyzes have been able to prove the increased overall mortality. These protective functions with which our body is endowed are very important, because our body is often confronted with megadoses of vitamins or other food stuff or unreasonable diets. Otherwise humans would already be extinct.
In summary, I would like to note that the human metabolism has many opportunities to compensate for unreasonable interventions for a limited time. The studies available so far relate to arachidonic acid intake with the Western Diet. This condition may already have provoked defense mechanisms that delay the occurrence of Western Diet diseases. We all agree that the Western Diet is too meat-based. The studies included in the review gave me the impression that an attempt had been made to further aggravate an already bad situation, present in Western civilizations. The negative result of these studies is reassuring for me, but does not mean that this supplementation has to be harmless and without long-term effects.
From my point of view, it would have been more productive from the experimental approach if vegans had been given the doses of arachidonic acid employed in the studies that are included in the review. This would come closer to the desired goal of the effects of arachidonic acid on PUFA status, metabolism and health-related outcomes in humans. Then one could also come to a result for the desirable intake of arachidonic acid, which I estimate for patients with inflammatory rheumatic diseases at 80 mg per day, corresponding to 560 mg per week. This corresponds to a diet with 5 vegan days and 2 days with consumption of animal products per week.If n3 is at sufficient levels, I see no reason to believe the n3:n6 ratio should be of any concern in terms of health risks. All the evidence I’ve seen cited to support the claim that a given n3:n6 ratio raises risks of negative health outcomes has induced “unhealthy” n3:n6 ratios by dropping n3 levels to insufficiency.
It’s on that point that I believe there is no supporting evidence in humans, and the fears of an issue are rooted in speculation. Happy to be proven wrong, though!
Vijay p. Singh says, "Separately, on analyzing global COVID-19 mortality data and comparing it with 12 risk factors for mortality, they found unsaturated fat intake to be associated with increased mortality. This was based on the dietary fat patterns of 61 countries in the United Nations' Food and Agricultural Organization database. Surprisingly, they found saturated fats to be protective."https://www.medpagetoday.com/reading-room/aga/lower-gi/86940
It's interesting that fasting and exercise furnish some protection from excessive polyunsaturated fatty acid intake. For example, "The increased proportional intake of dietary fat, decrease in feeding frequency and increased physical activity in free-ranging compared to captive cheetahs are all predicted to result in enhanced mitochondrial FA oxidation through the lowering of circulating glucose concentrations and insulin:glucagon ratios. During fasting/refeeding cycles and increased levels of exercise, tissue PUFA concentrations have been shown to deplete rapidly in both humans and rats. These studies show that most PUFAs, including α-linolenic acid (ALA) and linoleic acid (LA), are preferentially oxidized in periods of exercise or fasting. During refeeding, SFAs and monounsaturated fatty acids (MUFAs), such as palmitic acid and oleic acid, are also more rapidly replaced than any of the PUFAs. Similarly, the concentrations of most plasma PUFAs and MUFAs have been shown to be significantly lower in rats fed a high fat ketogenic diet than in controls. The predicted increase in FA oxidation in free-ranging cheetahs is therefore likely to also skew their serum FA profiles toward lower proportional serum concentrations of PUFAs and MUFAs relative to SFA." https://pmc.ncbi.nlm.nih.gov/articles/PMC5167222/
In the final analysis, dietary saturated fats are benign, if not outright beneficial over a wide range of intakes as long as they are consumed in the context of healthy nutrient configuration as in whole foods. https://pmc.ncbi.nlm.nih.gov/articles/PMC7846167/
The COVID one is disappointing. I was expecting a longitudinal study where they perhaps hadn’t adjusted for confounding variables like obesity, etc. Unfortunately, the reality is far worse.
The only human outcome data they seem to have is a cross-sectional analysis where (as far as I can tell, correct me if I’m wrong) they just looked at gross consumption at a national level of different FA types, then saw if there was an association with COVID mortality. This is an insane way to test the hypothesis “consumption of n6 increases Covid mortality.” It just isn’t evidence at all.
I would take evidence to be something that is expected on a given hypothesis and not the negation of that hypothesis. For example, “we see the sun rise in the sky” is not evidence supporting the hypothesis “the sun orbits the earth”, because it would also be expected on the negation of that hypothesis, for example under another hypothesis: “the earth orbits the sun”.
In this case, we can think of any number of hypotheses that negate the hypothesis “n6 consumption increases covid mortality”. For example, “n6 consumption proxies for junk food consumption and population obesity, which increases COVID mortality.” The outcomes of the study are equally expected on both hypotheses. The outcomes they’re seeing could be explained by this alternate hypothesis, for all we know.
Fundamentally, though, there’s actually a much bigger issue here - the data are just cross-sectional. We have no idea if the increased COVID mortality is even taking place in the people that consumed more UFA - the data just don’t tell us!
This leads to an awkward bullet-bite one has to make in order to make a causal inference from data like these: you would also have to affirm that smoking increases lifespan. Unadjusted cross-sectional data shows that countries with greater cigarette consumption have longer lifespan (http://web.archive.org/web/20220325085356/http://www.thefunc...). Now, clearly this is not because of the beneficial effects of smoking. Perhaps it’s because more cigarette consumption occurs in those countries that are wealthier. The point is, cross sectional data is unsuitable for making causal inferences like this.
The rest is just mechanistic speculation and animal studies, not something that can be extrapolated to human outcomes (more about why later). So the study doesn’t actually show any negative health outcomes in humans from n6 consumption.
The next study is literally a study of cheetahs. Might be of interest if you’re a cheetah, or deciding on your pet cheetah’s diet. But we’re talking about human health here.
And then the final paper suffers from the issue of earlier one - trying to make a causal inference based on cross-sectional data. We have zero idea if the individuals suffering from SAP are even the ones consuming more n6s. Again, if we are to find this convincing evidence of n6 toxicity then we also have to grant that cigarette consumption increases lifespan.
A commonality in these studies is that they try to back up the cross sectional data with animal modelling and in vitro studies, but we have to bear in mind that the best data we have on translation of animal studies to human outcomes suggests the success rate is atrocious. The confidence interval for toxicity studies in animal studies translating to human outcomes includes .5, so you may well be better off tossing a coin than you are relying on animal studies to make inferences about human health outcomes: https://translational-medicine.biomedcentral.com/articles/10...
To sum up, this seems to be a collection of data from the lower end of the evidence hierarchy, none of which is even in the category of data suitable to provide information about what is healthful or harmful to humans. I don’t see why we would find this convincing evidence of n6 toxicity on its own, even before we get into all the much higher quality evidence pointing to benefits from n6 consumption.
(1996) "Excessive signaling of arachidonic acid (AA) metabolites has been associated with various chronic degenerative or autoimmune diseases, and intervention with the metabolism of AA is widely employed therapeutically in these afflictions. In essence, AA is the most biologically active unsaturated fatty acid in higher animals. Its concentration in membranes and its magnitude of effects depend on its amount, or that of its precursors and analogues, in the diet. The tendency of the field of nutrition to ignore the role of dietary AA will optimistically be reversed in the future." The article also said, "The underlying rationale for this symposium is that dietary AA is perhaps the single most important nutritional determinant in regulating AA levels in Americans. This may ultimately account in part for the striking differences in chronic diseases between strict vegetarians and the bulk of the omnivorous population." https://pubmed.ncbi.nlm.nih.gov/8642436/
What unique feedback mechanism is this and how can i find out if i have this too ? circular reasoning "what makes them different is that they are shown to be different"
> they manage to escape heart attacks because their vessels are larger than average. Wow. I don’t know what to make of the Masai, except that they are indeed a unique people.
Maybe they are not "unique people" and there are other non-genetic reasons their blood vessels are larger.
I call BS on this so called review because author didn't bother to explain his points.
Get a blood lipids panel and see what your ApoB is like!
> Maybe they are not "unique people" and there are other non-genetic reasons their blood vessels are larger.
I don't think this effect has been observed in post mortem of other populations, so that would make them fairly unique, no?
not sure how this tell me if i have 'unique feedback mechanism' . wtf does that phrase even mean.
So you could get your LDL-c checked, up your butter consumption and then get a retest and compare the results to the expected value.
Biss, K., Ho, K.-J., Mikkelson, B., Lewis, L. & Taylor, C. B. Some Unique Biologic Characteristics of the Masai of East Africa. N. Engl. J. Med. 284, 694–699 (1971).
This is just an hypothesis that says they "may" have adaption? Not sure how that translates to definitive "they have a unique feedback mechanism "
If so, I have some wonderful things to show you from Teicholz that will have you rolling on the floor with laughter compared to Yoder’s stuff.
That certainty is what led me to believe i can look up genetic markers in my 23andme.
I did read the book and it seemed well cited.
If there are no more credible reviews do you care to substantiate your specific concerns with her work?
Just read the critique, ignore whatever “spamtaculous” things you’re seeing on the site. The content of the review is what we should care about. Happy to discuss that.
Much like in her book, Nina is grossly misrepresenting the evidence, and I’d say just flat-out lies or at the very least misleads the author. See my comment here for an example: https://news.ycombinator.com/item?id=41958014
To me it’s no secret that the mainstream nutrition science is a joke. The latest Nordic nutrition guidelines I’ve heard of recommend the same amount of sugar and red meat per week — 350 grams.
If that’s not enough to tell you everything these organisations do is based on false premises, I have a bridge to sell you.
Why?
Personally, I think that’s hilarious. Enjoy your bacon and butter.
I repeatedly found that people who are thoughtful and not snarky — and often, nuanced — when discussing a topic I have no deep expertise on were much more correct on topics that I did have expertise on and could properly evaluate.
We're all on a time budget at the end of the day. And I do share the sentiment: the scientific literature in nutrition is known not to be very good. You don't have to be an expert, it suffices to notice that there are a lot of people coming to contradictory conclusions, and that the consensus seems to have changed drastically over the past decades, not being particularly driven by any groundbreaking changes in available scientific methods.
Teicholz is considerably snarkier than Willett so, even by that metric, you should lean in favour of Willett’s position that SFA is unhealthy, I guess?
As for my personal position, I remember looking into things a while back and just coming away with the conclusion that nobody really seemed to know. If there's a truth here, it's either considerably more complex than "SFA good" / "SFA bad" (all these interacting pathways, man), or it just makes little enough difference not to matter at all in a way that we can meaningfully measure above the noise.
It seemed clear SFA are clearly not that deadly. Whether you'd be more healthy or live slightly longer if you chose to consume less of them, I have absolutely no clue.
I’m not sure how you’re determining that it’s otherwise?
Tone is something that can be adopted intentionally or unintentionally. If you hear a pilot on a radio dryly say something in a calm and detached tone, it could be in the context of an emergency. Pilots are enculturated to adopt that tone (for various reasons). Meanwhile particular cultures have different levels of acceptability when it comes to tone: some cultures perceive other cultures as more angry, or detached, because of the norms of communication within those cultures.
In short, I think the tone of “calm, scientific detachment” is often weaponized to lend undeserved credibility to an argument, because people tend to believe people more when they adopt that tone.
Furthermore, tone does have a purpose if used alongside a well done argument. For example, in the article the OP linked to, there is a rather exhaustive refutation of the book in question. The tone of the author previews that their entire opinion on the book is negative, given all the arguments they put forth in their review. If the author of the review had adopted a calm and thoughtful tone, perhaps it would indeed have been more effective because the reader would decide. On the other hand, most people won’t read the entire review, so the tone of the author makes it clear what their opinion is.
That said I am not wholly disagreeing with you: would be interesting to do a study using some varying markers to identify tone, and identify, I don’t know, argumentative complexity, and see if snarkiness is associated with a lack of complexity. Assuming you can find markers with predictive power.
Even that attitude can be weaponized I suppose, if nuance convinced more people, than more people would learn to fake nuance to push their favorite outcome. Though I'd like to think that the process would change them a little bit for the better too.
Seems a waste of effort trying to attribute motive to such things. Just read what they have to say, verify what they say against their references and then make an inference based on that. Don’t see why tone has to come into it at all.
I'm much more likely to listen to a person who has a calm, neutral or positive tone than someone who is screaming the same words at me.
Words are only a part of human communication, and arguably not the most important part.
"Can I help you?" Has a vastly different meaning depending on the tone and body language of the speaker.
I claimed that Teicholz was a joke because she makes misleading and often false claims about nutrition science evidence. The response was that the critique I linked to was more of a joke, not because of its content but because of its tone.
So sure, tone matters in certain contexts. If it matters more to someone than the content of what is being said to someone in the context of assessing scientific research, then I think that person has a wild way of interpreting evidence.
Very true. This fact has been deeply exploited by con men across social media in the past decade. When someone knows they’re coming from an unfounded, misleading, or deliberately wrong position they make up for it by heaping on friendly tone. They present in a warm, welcoming, and empathetic tone that appears inviting and friendly, unlike the cold academic discussions where facts reign supreme and tone is an afterthought.
It’s a real problem right now. There are countless influencers and podcasters pushing bad science who get a free pass because they are all smiles, super nice, and present themselves as helping you (while pitching you products and trying to get you to buy their book)
The other kind is heavier on snark than it is on evidence. It uses the snark to persuade, rather than the evidence. That's "I can't be bothered to actually make a real case here (whether or not the data is actually on my side), so I'm just going to make the other side look stupid, and hope that you decide to agree with me so that you don't feel stupid too".
The first kind can be persuasive. (In fact, it can be more persuasive than the dry kind of refutation.) The second kind is a huge red flag - if they're right, it's only by accident, because they can't be bothered to really deal with the evidence.
I suspect that, when different people are reacting to snark in such an article, they're reacting to different versions of it.
Please provide a source. The Danish health authorities absolutely do NOT recommend sugar consumption. Instead, they recommend eating 600g of fruits and vegetables, 100g of legumes, 30g of nuts, and 90g of whole grains DAILY, as well as 350g of fish and no more than 350g of meat WEEKLY. Source: https://foedevarestyrelsen.dk/Media/638651862095615836/AOK-a...
Out of curiosity, what fish are popular among Danes?
Also what do they say about milk and cheese? Any particular cheese is healthier?
Hi KempyKolibri. Was this intervention so important that you needed to signup for HackerNews for the first time to call her a joke ? I think this is quite against this forum guideline but (unsurprisingly) you are being upvoted.