Early Research On the Industrial Diet

By the early 1900s, the modern diet had long been a growing concern, as it already was a topic of public debate going back a century, such as obesity and conditions like ‘nerves’. This public health issue became a moral panic with tuberculosis and neurasthenia that was linked to diet. Much of the focus was scientific study. Many vitamins and micronutrients were being discovered and researched.

Also, the industrial seed oils were being linked to ill health right from the start; although not yet understood as oxidative, inflammatory, and mutagenic. The initial observations were being made on farm animals being fed “on by-products from margarine factories”, as advised by feeding experts. It would be decades later that a mass experiment would be initiated on humans when, in the 1930s, industrial seed oils replaced animal fats as the main source of fatty acids in the American diet.

The following decades after that in the post-war period would begin the public health crisis of skyrocketing rates of metabolic syndrome: obesity, heart disease, strokes, diabetes, etc. But long before that, the health decline was already becoming apparent to many, such as Dr. Weston A. Price and Dr. Francis M. Pottenger Jr, and even earlier with Dr. Claude Bernard, Dr. William Harvey, Dr. James H. Salisbury, etc. Another example of someone on the leading edge was Dr. M. J. Rowlands.

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Rheumatoid Arthritis: Is it a Deficiency Disease?
By M. J. Rowlands, M.D.
May 25, 1927

My clinical investigations began as far back as 1912, when I installed an X-ray apparatus with the idea of trying to find out what similarity there was in the lesions amongst my cases. In the war during 1914 and 1915 stationed at Netley. The blood-cultures and joint punctures I carried out proved sterile.

Owing to ill-health I had to relinquish the Service for some time; I returned to it again in 1916 and was given the pathological charge of three hospitals of some 2,000 patients, where I could place as many rheumatoid patients for whom I could find beds, an order being posted in the London area that all true rheumatoids were to be sent to one of my hospitals. In this way I was able to accumulate some 200 rheumatoids and keep them for investigation. But with all this opportunity and all the advantages of able assistance and cordial help for over three years, until May, 1919, nothing of great value was discoverable. In 1916 I wrote a paper which was published in the Lancet1 giving the results of my investigations up to that time.

After the war I again took up the investigation of this disease chiefly owing to my farming instinct. The question of vitamins and the work of Hopkins, Funk, Plimmer and Drummond, was being published. I began to experiment with pigs, as I found that a large number of my pigs which were bred on the open-air system were from time to time suffering from marked stiffness and swollen joints. I began to feed my animals on a full vitamin diet and the result of these experiments was marvellous. There was a complete change in the condition of my herd and I decided to show my experimental animals at the largest Fat Stock Show in the world-namely, Smithfield. The result of the first time of showing was every possible prize that I could have won as well as the Cup. This gave me ample proof that in animals’ malnutrition lay the seat of investigation. In 1921 I read a paper before the Farmers’ Club at the Surveyors’ Institute discussing my experiments. Professor T. B. Wood, of Cambridge, and Dr. Crowther, Principal of the Harper Adams College, who opened the discussion, ridiculed all my experiments, and the whole idea of vitamins, and, in fact, the only member of the audience who agreed was Lord Bledisloe. To-day I think both Professor Wood and Dr. Crowther are aware of the value of vitamins and now admit their use to the British farmer. […]

I had by me all the notes of an experiment I had carried out a few years previously. Feeding experts were constantly advising farmers-and are doing so to-day-to feed their pigs on by-products from margarine factories, such as palm kernels, coco-nut, earth-nut, soya beans, etc. So I placed three pens of pigs on these foods as a test, using against them a food containing meat, yeast, cod-liver oil and a salt mixture, the carbohydrate content of the diet being the same in all the pens. Within a few weeks it became apparent that the pigs on a diet of palm-kernel and coco-nut were rapidly going downhill; and at the end of the test the pigs fed on my mixture had increased by 143 lb., and for every 1 lb. of increase in weight had consumed 2 * 62 lb., whereas the ” palm kernel pigs ” had increased only 40 lb., and for every 1 lb. of increased weight they had consumed 5 lb. The palm kernel pigs showed a vitamin B deficiency. […]

In dealing with the deficiency of vitamin B in cases of rheumatism, Dr. Rowlands’ paper was convincing and dramatic, but the relationship between this deficiency and the various forms of rheumatism was not clearly shown. Whereas it was probably a factor in rheumatoid arthritis, the co-relation was not evident in either osteo-arthritis, with its prevailing characteristic of robustness, or in the climacteric type associated with thyroid deficiency. Possibly there were other vitamin deficiencies-an “A” deficiency and probably a “D” deficiency-concerned in the control of phosphates, […]

Rheumatoid arthritis was certainly a deficiency disease, and the deficiency was connected with the assimilation or utilization of phosphoric acid and other phosphates, so that probably vitamins B and D were often associated with it. Rheumatoid arthritis never attacked the bon viveur or the alcoholic, but was the disease of the total abstainer, the vegetarian and the careful liver. […]

An important point which none of the discussers had mentioned was the great change in our diet, not so much in our own choice of food, but in the food of the animals on which we depended so much for our own. For instance, cows used to be fed on ground oats, ground wheat, ground barley, ground rye; all these contained the essential vitamin B. To-day very few farmers gave such food to their cattle; instead, they gave cotton-seed cake, linseed cake, and all kinds of patent foods which were deficient in vitamin B, and therefore. milk was not now so good as in former days. Chickens, again, were now fed on all sorts of material, and were the subjects of intensive culture, with the result that the egg-yolk was not of the same value as formerly. Vitamin B was not an animal product, it must be supplied to the animal from some outside source.

Dietary Risk Factors for Heart Disease and Cancer

Based on a study of 42 European countries, a recent scientific paper reported that, “the highest CVD [cardiovascular disease] prevalence can be found in countries with the highest carbohydrate consumption, whereas the lowest CVD prevalence is typical of countries with the highest intake of fat and protein.” And that, “The positive effect of low-carbohydrate diets on CVD risk factors (obesity, blood lipids, blood glucose, insulin, blood pressure) is already apparent in short-term clinical trials lasting 3–36 months (58) and low-carbohydrate diets also appear superior to low-fat diets in this regard (36, 37).” Basically, for heart health, this would suggest eating more full-fat dairy, eggs, meat, and fish while eating less starches, sugar, and alcohol. That is to say, follow a low-carb diet. It doesn’t mean eat any low-carb diet, though, for the focus is on animal foods.

By the way, when you dig into the actual history of the Blue Zones (healthy, long-lived populations), what you find is that their traditional diets included large portions of animal foods, including animal fat (Blue Zones Dietary Myth, Eat Beef and Bacon!, Ancient Greek View on Olive Oil as Part of the Healthy Mediterranean Diet). The longest-lived society in the entire world, in fact, is also the one with the highest meat consumption per capita, even more than Americans. What society is that? Hong Kong. In general, nutrition studies in Asia has long shown that those eating more meat have the best health outcomes. This contradicts earlier Western research, as we’re dealing with how the healthy user effect manifests differently according to culture. But even in the West, the research is ever more falling in line with the Eastern research, such as with the study I quoted above. And that study is far from being the only one (Are ‘vegetarians’ or ‘carnivores’ healthier?).

This would apply to both meat-eaters and vegetarians, as even vegetarians could put greater emphasis on nutrient-dense animal foods. It is specifically saturated fat and animal proteins that were most strongly associated with better health, both of which could be obtained from dairy and eggs. Vegans, on the other hand, would obviously be deficient in this area. But certain plant foods (tree nuts, olives, citrus fruits, low-glycemic vegetables, and wine, though not distilled beverages) also showed some benefit. Considering plant foods, those specifically associated with greater risk of heart disease, strokes, etc were those high in carbohydrates such as grains. Unsurprisingly, sunflower oil was a risk factor, probably related to seed oils being inflammatory and oxidative (not to mention mutagenic); but oddly onions were also likewise implicated, if only weakly. Other foods showed up in the data, but the above were the most interesting and important.

Such correlations, of course, can’t prove causation. But it fits the accumulating evidence: “These findings strikingly contradict the traditional ‘saturated fat hypothesis’, but in reality, they are compatible with the evidence accumulated from observational studies that points to both high glycaemic index and high glycaemic load (the amount of consumed carbohydrates × their glycaemic index) as important triggers of CVDs. The highest glycaemic indices (GI) out of all basic food sources can be found in potatoes and cereal products, which also have one of the highest food insulin indices (FII) that betray their ability to increase insulin levels.” All of that seems straightforward, according to the overall data from nutrition studies (see: Uffe Ravnskov, Richard Smith, Robert Lustig, Eric Westman, Ben Bikman, Gary Taubes, Nina Teicholz, etc). About saturated fat not being linked to CVD risk, Andrew Mente discusses a meta-analysis he worked on and another meta-analysis by another group of researchers, Siri-Tarino PW et al (New Evidence Reveals that Saturated Fat Does Not Increase the Risk of Cardiovascular Disease). Likewise, many experts no longer see cholesterol as a culprit either (Uffe Ravnskov et al, LDL-C does not cause cardiovascular disease: a comprehensive review of the current literature).

Yet one other odd association was discovered: “In fact, our ecological comparison of cancer incidence in 39 European countries (for 2012; (59)) can bring another important argument. Current rates of cancer incidence in Europe are namely the exact geographical opposite of CVDs (see Fig. 28). In sharp contrast to CVDs, cancer correlates with the consumption of animal food (particularly animal fat), alcohol, a high dietary protein quality, high cholesterol levels, high health expenditure, and above average height. These contrasting patterns mirror physiological mechanisms underlying physical growth and the development of cancer and CVDs (60). The best example of this health paradox is again that of French men, who have the lowest rates of CVD mortality in Europe, but the highest rates of cancer incidence. In other words, cancer and CVDs appear to express two extremes of a fundamental metabolic disbalance that is related to factors such as cholesterol and IGF-1 (insulin-like growth factor).”

That is an argument people have made, but it’s largely been theoretical. In response, others have argued the opposite position (High vs Low Protein, Too Much Protein?, Gundry’s Plant Paradox and Saladino’s Carnivory, Carcinogenic Grains). It’s true that, for example, eating meat increases IGF-1, at least temporarily. Then again, eating in general does the same. And on a diet low enough in carbs, it’s been shown in studies that people naturally reduce their calorie intake, which would reduce IGF-1. And for really low-carb, the ketogenic diet is specifically defined as being low in animal protein while higher in fat. A low-carb diet is not necessarily a high-animal protein diet, especially when combined with intermittent fasting such as OMAD (one meal a day) with long periods of downregulated IGF-1. Also, this study didn’t appear to include plant proteins in the data, and so we don’t know if eating lots of soy, hemp protein powder, etc would show similar results; although nuts were mentioned in the report as being similar to meat in correlating to CVD health but, as far as I know, not mentioned in terms of cancer. What would make animal proteins more carcinogenic than plant proteins or, for that matter, plant carbohydrates? The hypothetical mechanism is not clear.

This anomaly would’ve been more interesting if the authors had surveyed the research literature. It’s hard to know what to make of it since other studies have pointed to the opposite conclusion, that the risks of these two are closely linked, rather than being inversely associated: “Epidemiologically, a healthy lifestyle lessens the risk of both cardiovascular disease and cancer, as first found in the Nurses’ Health study” (Lionel Opie, Cancer and cardiovascular disease; see Rob M. Van Dam, Combined impact of lifestyle factors on mortality). “Research has shown there are interrelationships among type 2 diabetes, heart disease, and cancer. These interrelationships may seem coincidental and based only on the fact these conditions share common risk factors. However, research suggests these diseases may relate to one another in multiple ways and that nutrition and lifestyle strategies used to prevent and manage these diseases overlap considerably” (Karen Collins, The Cancer, Diabetes, and Heart Disease Link).

Yet other researchers did find the same inverse relationship: “We herein report that, based on two separate medical records analysis, an inverse correlation between cancer and atherosclerosis” (Matthew Li et al, If It’s Not One Thing, It’s Another). But there was an additional point: “We believe that the anti-inflammatory aspect of cancer’s pan-inflammatory response plays an important role towards atherosclerotic attenuation.” Interesting! In that case, one of the key causal mechanisms to be considered is inflammation. Some diets high in animal proteins would be inflammatory, such as the Standard American Diet, whereas others would be anti-inflammatory. Eliminating seed oils (e.g., sunflower oil) would by itself reduce inflammation. Reducing starches and sugar would help as well. So, is it the meat that increases cancer or is it what the meat is being cooked in or eaten with? That goes back to the healthy and unhealthy user effects.

As this confounding factor is central, we might want to consider the increasingly common view that inflammation is involved in nearly every major disease. “For example, inflammation causes or is a causal link in many health problems or otherwise seen as an indicator of health deterioration (arthritis, depression, schizophrenia, etc), but inflammation itself isn’t the fundamental cause since it is a protective response itself to something else (allergens, leaky gut, etc). Or as yet another example, there is the theory that cholesterol plaque in arteries doesn’t cause the problem but is a response to it, as the cholesterol is essentially forming a scab in seeking to heal injury. Pointing at cholesterol would be like making accusations about firefighters being present at fires” (Coping Mechanisms of Health).

What exacerbates or moderates inflammation will be pivotal to overall health (Essentialism On the Decline), especially the nexus of disease called metabolic syndrome/derangement or what used to be called syndrome X: insulin resistance, diabetes, obesity, heart disease, strokes, etc. In fact, other researchers point directly to inflammation as being a common factor of CVD and cancer: “Although commonly thought of as two separate disease entities, CVD and cancer possess various similarities and possible interactions, including a number of similar risk factors (e.g. obesity, diabetes), suggesting a shared biology for which there is emerging evidence. While chronic inflammation is an indispensible feature of the pathogenesis and progression of both CVD and cancer, additional mechanisms can be found at their intersection” (Ryan J. Koene et al, Shared Risk Factors in Cardiovascular Disease and Cancer). But it might depend on the specific conditions how inflammation manifests as disease — not only CVD or cancer but also arthritis, depression, Alzheimer’s, etc.

This is the major downfall of nutrition studies, as the experts in the field find themselves hopelessly mired in a replication crisis. There is too much contradictory research and, when much of the research has been repeated, it simply did not replicate. That is to say much of it is simply wrong or misinterpreted. And as few have attempted to replicate much of it, we aren’t entirely sure what is valid and what is not. That further problemetizes meta-analyses, despite how potentially powerful that tool can be when working with quality research. The study I’ve been discussing here was an ecological study and that has its limitations. The researchers couldn’t disentangle all the major confounding factors, much less control for them in the first place, as they were working with data across decades that came from separate countries. Even so, it’s interesting and useful info to consider. And keep in mind that almost all official dietary recommendations are based on observational (associative, correlative, epidemiological) studies with far fewer controls. This is the nature of the entire field of nutrition studies, as long-term randomized and controlled studies on humans are next to impossible to do.

So, as always, qualifications must be made. The study’s authors state that, “In items of smaller importance (e.g. distilled beverages, sunflower oil, onions), the results are less persuasive and their interpretation is not always easy and straightforward. Similar to observational studies, our ecological study reflects ‘real-world data’ and cannot always separate mutual interactions among the examined variables. Therefore, the reliance on bivariate correlations could lead to misleading conclusions. However, some of these findings can be used as a starting point of medical hypotheses, whose validity can be investigated in controlled clinical trials.” Nonetheless, “The reasonably high accuracy of the input data, combined with some extremely high correlations, together substantially increase the likelihood of true causal relationships, especially when the results concern principal components of food with high consumption rates, and when they can be supported by other sources.”

This data is meaningful in offering strong supporting evidence. The finding about animal foods and starchy foods is the main takeaway, however tentative the conclusion may be for real world application, at least in taking this evidence in isolation. But the inverse correlation of CVD risk and cancer risk stands out and probably indicates confounders across populations, and that would be fertile territory for other researchers to explore. The main importance to this study is less in the specifics and more in how it further challenges the broad paradigm that has dominated nutrition studies for the past half century or so. The most basic point is that the diet-heart hypothesis simply doesn’t make sense of the evidence and it never really did. When the hypothesis was first argued, heart disease was going up precisely at the moment saturated fat intake was going down, since seed oils had replaced lard as the main fat source in the decades prior. Interestingly, lard has been a common denominator among most long-lived populations, from the Okinawans to Rosetans (Ancient Greek View on Olive Oil as Part of the Healthy Mediterranean Die, Blue Zones Dietary Myth).

This study is further support for a new emerging understanding, as seen with the American Heart Association backing off from its earlier position (Slow, Quiet, and Reluctant Changes to Official Dietary Guidelines). Fat is not the enemy of humanity, as seen with the high-fat ketogenic diet where fat is used as the primary fuel, instead of carbohydrates (Ketogenic Diet and Neurocognitive Health, The Ketogenic Miracle Cure, The Agricultural Mind). In fact, we wouldn’t be here without fat, as it is the evolutionary and physiological norm, specifically in terms of low-carb (Is Ketosis Normal?, “Is keto safe for kids?”). Instead, that too many carbohydrates are unhealthy used to be common knowledge (American Heart Association’s “Fat and Cholesterol Counter” (1991)). Consensus on this shifted a half century ago, the last time when low-carb diets were still part of mainstream thought, and now we are shifting back the other way. The old consensus will be new again.

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Carbohydrates, not animal fats, linked to heart disease across 42 European countries
by Keir Watson

Key findings

  • Cholesterol levels were tightly correlated to the consumption of animal fats and proteins – Countries consuming more fat and protein from animal sources had higher incidence of raised cholesterol
  • Raised cholesterol correlated negatively with CVD risk – Countries with higher levels of raised cholesterol had fewer cases of CVD deaths and a lower incidence of CVD risk factors
  • Carbohydrates correlated positively with CVD risk – the more carbohydrates consumed (and especially those with high GI such as starches) the more CVD
  • Fat and Protein correlated negatively with CVD risk – Countries consuming more fat and protein from animal and plant sources had less CVD. The authors speculate that this is because increasing fat and protein in the diet generally displaces carbohydrates.

Food consumption and the actual statistics of cardiovascular diseases: an epidemiological comparison of 42 European countries
Pavel Grasgruber,* Martin Sebera, Eduard Hrazdira, Sylva Hrebickova, and Jan Cacek

Results

We found exceptionally strong relationships between some of the examined factors, the highest being a correlation between raised cholesterol in men and the combined consumption of animal fat and animal protein (r=0.92, p<0.001). The most significant dietary correlate of low CVD risk was high total fat and animal protein consumption. Additional statistical analyses further highlighted citrus fruits, high-fat dairy (cheese) and tree nuts. Among other non-dietary factors, health expenditure showed by far the highest correlation coefficients. The major correlate of high CVD risk was the proportion of energy from carbohydrates and alcohol, or from potato and cereal carbohydrates. Similar patterns were observed between food consumption and CVD statistics from the period 1980–2000, which shows that these relationships are stable over time. However, we found striking discrepancies in men’s CVD statistics from 1980 and 1990, which can probably explain the origin of the ‘saturated fat hypothesis’ that influenced public health policies in the following decades.

Conclusion

Our results do not support the association between CVDs and saturated fat, which is still contained in official dietary guidelines. Instead, they agree with data accumulated from recent studies that link CVD risk with the high glycaemic index/load of carbohydrate-based diets. In the absence of any scientific evidence connecting saturated fat with CVDs, these findings show that current dietary recommendations regarding CVDs should be seriously reconsidered. […]

Irrespective of the possible limitations of the ecological study design, the undisputable finding of our paper is the fact that the highest CVD prevalence can be found in countries with the highest carbohydrate consumption, whereas the lowest CVD prevalence is typical of countries with the highest intake of fat and protein. The polarity between these geographical patterns is striking. At the same time, it is important to emphasise that we are dealing with the most essential components of the everyday diet.

Health expenditure – the main confounder in this study – is clearly related to CVD mortality, but its influence is not apparent in the case of raised blood pressure or blood glucose, which depend on the individual lifestyle. It is also difficult to imagine that health expenditure would be able to completely reverse the connection between nutrition and all the selected CVD indicators. Therefore, the strong ecological relationship between CVD prevalence and carbohydrate consumption is a serious challenge to the current concepts of the aetiology of CVD.

The positive effect of low-carbohydrate diets on CVD risk factors (obesity, blood lipids, blood glucose, insulin, blood pressure) is already apparent in short-term clinical trials lasting 3–36 months (58) and low-carbohydrate diets also appear superior to low-fat diets in this regard (36, 37). However, these findings are still not reflected by official dietary recommendations that continue to perpetuate the unproven connection between saturated fat and CVDs (25). Understandably, because of the chronic nature of CVDs, the evidence for the connection between carbohydrates and CVD events/mortality comes mainly from longitudinal observational studies and there is a lack of long-term clinical trials that would provide definitive proof of such a connection. Therefore, our data based on long-term statistics of food consumption can be important for the direction of future research.

In fact, our ecological comparison of cancer incidence in 39 European countries (for 2012; (59)) can bring another important argument. Current rates of cancer incidence in Europe are namely the exact geographical opposite of CVDs (see Fig. 28). In sharp contrast to CVDs, cancer correlates with the consumption of animal food (particularly animal fat), alcohol, a high dietary protein quality, high cholesterol levels, high health expenditure, and above average height. These contrasting patterns mirror physiological mechanisms underlying physical growth and the development of cancer and CVDs (60). The best example of this health paradox is again that of French men, who have the lowest rates of CVD mortality in Europe, but the highest rates of cancer incidence. In other words, cancer and CVDs appear to express two extremes of a fundamental metabolic disbalance that is related to factors such as cholesterol and IGF-1 (insulin-like growth factor).

Besides total fat and protein consumption, the most likely preventive factors emerging in our study include fruits (particularly citrus fruits), wine, high-fat dairy products (especially cheese), sources of plant fat (tree nuts, olives), and potentially even vegetables and other low-glycaemic plant sources, provided that they substitute high-glycaemic foods. Many of these foodstuffs are the traditional components of the ‘Mediterranean diet’, which again strengthens the meaningfulness of our results. The factor analysis (Factor 3) also highlighted coffee, soybean oil and fish & seafood, but except for the fish & seafood, the rationale of this finding is less clear, because coffee is strongly associated with fruit consumption and soybean oil is used for various culinary purposes. Still, some support for the preventive role of coffee does exist (61) and hence, this observation should not be disregarded.

Similar to the “Mediterranean diet”, the Dietary Approaches to Stop Hypertension (DASH) diet, which is based mainly on fruits, vegetables, and low-fat dairy, also proved to be quite effective (62). However, our data indicate that the consumption of low-fat dairy may not be an optimal strategy. Considering the unreliability of observational studies highlighting low-fat dairy and the existence of strong bias regarding the intake of saturated fat, the health effect of various dairy products should be carefully tested in controlled clinical studies. In any case, our findings indicate that citrus fruits, high-fat dairy (such as cheese) and tree nuts (walnuts) constitute the most promising components of a prevention diet.

Among other potential triggers of CVDs, we should especially stress distilled beverages, which consistently correlate with CVD risk, in the absence of any relationship with health expenditure. The possible role of sunflower oil and onions is much less clear. Although sunflower oil consistently correlates with stroke mortality in the historical comparison and creates very productive regression models with some correlates of the actual CVD mortality, it is possible that both these food items mirror an environment that is deficient in some important factors correlating negatively with CVD risk.

A very important case is that of cereals because whole grain cereals are often propagated as CVD prevention. It is true that whole grain cereals are usually characterised by lower GI and FII values than refined cereals, and their benefits have been documented in numerous observational studies (63), but their consumption is also tied with a healthy lifestyle. All the available clinical trials have been of short duration and have produced inconsistent results indicating that the possible benefits are related to the substitution of refined cereals for whole grain cereals, and not because of whole grain cereals per se (64, 65). Our study cannot differentiate between refined and unrefined cereals, but both are highly concentrated sources of carbohydrates (~70–75% weight, ~80–90% energy) and cereals also make up ~50% of CA energy intake in general. To use an analogy with smoking, a switch from unfiltered to filtered cigarettes can reduce health risks, but this fact does not mean that filtered cigarettes should be propagated as part of a healthy lifestyle. In fact, even some unrefined cereals [such as the ‘whole-meal bread’ tested by Bao et al. (32)] have high glycaemic and insulin indices, and the values are often unpredictable. Therefore, in the light of the growing evidence pointing to the negative role of carbohydrates, and considering the lack of any association between saturated fat and CVDs, we are convinced that the current recommendations regarding diet and CVDs should be seriously reconsidered.

Are ‘vegetarians’ or ‘carnivores’ healthier?

Nutrition studies has been plagued with problems. Most of the research in the past was extremely low quality. Few other fields would allow such weak research to be published in peer-reviewed journals. Yet for generations, epidemiological (observational and correlational) studies were the norm for nutrition studies. This kind of research is fine for preliminary exploration in formulating new hypotheses to test, but it is entirely useless for proving or disproving any given hypothesis. Shockingly, almost all of medical advice and government recommendations on diet and nutrition are based on this superficial and misleading level of results.

The main problem is there has been little, if any, control of confounding factors. Also, the comparisons used were pathetically weak. It turns out that, in studies, almost any dietary protocol or change improves health compared to a standard American diet (SAD) or other varieties of standard industrialized diets based on processed foods of refined carbs (particularly wheat), added sugar (particularly high fructose corn syrup), omega-6 seed oils (inflammatory, oxidative, and mutagenic), food additives (from glutamate to propionate), and nutrient-deficient, chemical-drenched agricultural crops (glyphosate among the worst). Assuming the dog got decent food, even eating dog shit would be better for your health than SAD.

Stating that veganism or the Mediterranean diet is healthier than what most people eat really tells us nothing at all. That is even more true when the healthy user effect is not controlled for, as typically is the case with most studies. When comparing people on these diets to typical meat eaters, the ‘carnivores’ also are eating tons of carbs, sugar, and seed oils with their meat (buns, french fries, pop, etc; and, for cooking and in sauces, seed oils; not to mention snacking all day on chips, crackers, cookies, and candy). The average meat-eater consumes far more non-animal foods than animal foods, and most processed junk food is made mostly or entirely with vegan ingredients. So why do the animal foods get all the blame? And why does saturated fat get blamed when, starting back in the 1930s, seed oils replaced lard as the main source of cooking fat/oil?

If scientists in this field were genuinely curious, intellectually humble, not ideologically blinded, and unbiased by big food and big farm funding, they would make honest and fair comparisons to a wide variety of optimally-designed diets. Nutritionists have known about low-carb, keto, and carnivore diets for about a century. The desire to research these diets, however, has been slim to none. The first ever study of the carnivore diet, including fully meat-based, is happening right now. To give some credit, research has slowly been improving. I came across a 2013 study that compared four diets: “vegetarian, carnivorous diet rich in fruits and vegetables, carnivorous diet less rich in meat, and carnivorous diet rich in meat” (Nathalie T. Burkert et al, Nutrition and Health – The Association between Eating Behavior and Various Health Parameters: A Matched Sample Study).

It’s still kind of amusing that the researchers called carnivorous a “diet rich in fruits and vegetables” and a “diet less rich in meat.” If people are mostly eating plant foods or otherwise not eating much meat, how exactly is that carnivorous in any meaningful and practical sense? Only one in four of the diets were carnivorous in the sense the average person would understand it, as a diet largely based on animal foods. Even then, it doesn’t include a carnivorous diet entirely based on animal foods. Those carnivores eating a “diet rich in meat” might still be eating plenty of processed junk food, their meat might still be cooked or slathered in harmful seed oils and come with a bun, and they might still be washing it down with sugary drinks. A McDonald’s Big Mac meal could be considered as part of a diet rich in meat, just because meat represents the greatest portion of weight and calories. Even if their diet was only 5-10% unhealthy plant foods, it could still be doing severe damage to their health. One can fit in a fairly large amount of carbs, seed oils, etc in a relatively small portion of the diet.

I’m reminded of research that defines a “low-carb diet” as any carb intake that is 40% or below, but other studies show that 40% is the absolute highest point of carb intake for most hunter-gatherers (discussed here with links to references). As high and low are relative concepts in defining carb intake, what is considered a meat-rich diet would be relative as well. I doubt these studied carnivorous “diets rich in meat” are including as high amount of animal foods as found in the diets of Inuit, Masai, early Americans, and Paleolithic humans. So what is actually being compared and tested? It’s not clear. This was further confounded in how vegans, vegetarians, and pescetarians (fish-eaters) were combined into a single group mislabeled as ‘vegetarian’, considering that vegetarians and pescetarians technically could eat a diet primarily animal-based if they so chose (dairy, eggs, and/or fish) and I know plenty of vegetarians who eat more cheese than they do fruits and vegetables. Nonetheless, at least these researchers were making a better comparison than most studies. They did try to control for other confounders such as pairing each person on a plant-based diet with “a subject of the same sex, age, and SES [socioeconomic status]” from each of the other three diets.

What were the results? Vegetarians, compared to the most meat-based of the diets, had worse outcomes for numerous health conditions: asthma, allergies, diabetes, cataracts, tinnitus, cardiac infarction, bronchitis, sacrospinal complaints, osteoporosis, gastric or intestinal ulcer, cancer, migraine, mental illness (anxiety disorder or depression), and “other chronic conditions.” There were only a few health conditions where the plant-based dieters fared better. For example, the so-called ‘vegetarians’ had lower rates of hypertension compared to carnivores rich in meat and less rich in meat, although higher rates than those carnivores rich in fruits and vegetables (i.e., more typical omnivores).

This is interesting evidence about the diets, though. If the carnivorous diets were low enough in starchy and sugary plant foods and low enough in dairy, they would be ketogenic which in studies is known to lower blood pressure and so would show a lesser rate of hypertension. This indicates that none of these diets are low-carb, much less very low-carb (ketogenic). The plant-based dieters in this study also had lower rates of stroke and arthritis, these being other health benefits seen on a ketogenic diet, and so this further demonstrates that this study wasn’t comparing high-carb vs low-carb as one might expect from how the diets were described in the paper. That is to say the researchers didn’t include a category for a ketogenic carnivore diet or even a ketogenic omnivore diet, much less a ketogenic ‘vegetarian’ diet as a control. Keep in mind that keto-carnivore is one of the most common forms of those intentionally following a carnivore diet. And keep in mind that plant-based keto is probably more popular right now than keto-carnivore. So, the point is that these unexpected results are examples of the complications with confounding factors.

The only other result that showed an advantage to the ‘vegetarians’ was less urinary incontinence, which simply means they didn’t have to pee as often. I haven’t a clue what that might mean. If we were talking about low-carb and keto, I’d suspect that the increased urination for the ‘carnivorous’ diets was related to decreased water retention (i.e., bloating) and hence the water loss that happens as metabolism shifts toward fat-burning. But since we are confident that such a diet wasn’t included in the study, these results remain anomalous. Of all the things that meat gets blamed for, I’ve never heard of anyone suggesting that it causes most people to urinate incessantly. That is odd. Anyway, it’s not exactly a life-threatening condition, even if it were caused by carnivory. It might have something to do with higher-fat combined with higher-carb, in the way that this combination also contributes to obesity, whereas high-fat/low-carb and low-fat/high-carb does not predispose one to fat gain. The ‘vegetarianism’ in this study was being conflated with a low-fat diet, but all of the four categories apparently were varying degrees of higher carb.

The basic conclusion is that ‘vegetarians’, including vegans and pescetarians, have on average poorer health across the board, with a few possible exceptions. In particular, they suffer more from chronic diseases and report higher impairment from health disorders. Also, not only these ‘vegetarians’ but also meat-eaters who ate a largely plant-based diet (“rich in fruits and vegetables”) consult doctors more often, even as ‘vegetarians’ are inconsistent about preventative healthcare such as check-ups and vaccinations. Furthermore, “subjects with a lower animal fat intake demonstrate worse health care practices,” whatever that exactly means. Generally, ‘vegetarians’ “have a lower quality of life.”

These are interesting results since the researchers were controlling for such things as wealth and poverty, and so it wasn’t an issue of access to healthcare or the quality of one’s environment or level of education. The weakness is that no data was gathered on macronutrient ratios of the subjects’ diets, and no testing was done on micronutrient content in the food and potential deficiencies in the individuals. Based on these results, no conclusions can be made about causal direction and mechanisms, but it does agree with some other research that finds similar results, including with other health conditions such as vegans and vegetarians having greater infertility. Any single one of these results, especially something like infertility, points toward serious health concerns involving deeper systemic disease and disorder within the body.

But what really stands out is the high rate of mental illness among ‘vegetarians’ (about 10%), twice as high as the average meat-eater (about 5%) which is to say the average Westerner, and that is with the background of the Western world having experienced a drastic rise in mental illness over the past couple of centuries. And the only mental illnesses considered in this study were depression and anxiety. The percentage would be so much higher if including all other psychiatric conditions and neurocognitive disorders (personality disorders, psychosis, psychopathy, Alzheimer’s, ADHD, autism, learning disabilities, etc). Think about that, the large number of people on a plant-based diet who are struggling on the most basic level of functioning, something I personally understand from decades of chronic depression on the SAD diet. Would you willingly choose to go on a diet that guaranteed a high probability of causing mental health struggles and suffering, neurocognitive issues and decline?

To put this study in context, listen to what Dr. Paul Saladino, trained in psychiatry and internal medicine, has to say in the following video. Jump to around the 19 minute mark where he goes into the nutritional angle of a carnivore diet. And by carnivore he is talking about fully carnivore and so, if dairy is restricted as he does in his own eating, it would also mean ketogenic as well. A keto-carnivore diet has never been studied. Hopefully, that will change soon. Until then, we have brilliant minds like that of Dr. Saladino to dig into the best evidence that is presently available.

Here are a couple of articles that come from the BBC. As a mainstream news source, this demonstrates how this knowledge is finally getting acknowledged in conventional healthcare and public debate. That is heartening.

[Text below is from linked articles.]

Why vegan junk food may be even worse for your health
by William Clark, BBC

There’s also the concern that the health risks associated with these kinds of nutrient deficiencies might not show up immediately. It could take years to associate foggy thoughts and tiredness with low B12 levels, infertility with low iron, and osteoporosis brought on by calcium deficiency does not show up until late 40s and 50s in most people, says Rossi.

“People will think about their health now and not their future health,” she says.

How a vegan diet could affect your intelligence
by Zaria Gorvett, BBC

In fact, there are several important brain nutrients that simply do not exist in plants or fungi. Creatine, carnosine, taurine, EPA and DHA omega-3 (the third kind can be found in plants), haem iron and vitamins B12 and D3 generally only occur naturally in foods derived from animal products, though they can be synthesised in the lab or extracted from non-animal sources such as algae, bacteria or lichen, and added to supplements.

Others are found in vegan foods, but only in meagre amounts; to get the minimum amount of vitamin B6 required each day (1.3 mg) from one of the richest plant sources, potatoes, you’d have to eat about five cups’ worth (equivalent to roughly 750g or 1.6lb). Delicious, but not particularly practical. […]

There are small amounts of choline in lots of vegan staples, but among the richest sources are eggs, beef and seafood. In fact, even with a normal diet, 90% of Americans don’t consume enough. According to unpublished research by Wallace, vegetarians have the lowest intakes of any demographic. “They have extremely low levels of choline, to the point where it might be concerning,” he says.

For vegans, the picture is likely to be bleaker still, since people who eat eggs tend to have almost double the choline levels of those who don’t. And though the US authorities have set suggested intakes, they might be way off.

Meat and mental health: a systematic review of meat abstention and depression, anxiety, and related phenomena
by Urska Dobersek et al

Conclusion: Studies examining the relation between the consumption or avoidance of meat and psychological health varied substantially in methodologic rigor, validity of interpretation, and confidence in results. The majority of studies, and especially the higher quality studies, showed that those who avoided meat consumption had significantly higher rates or risk of depression, anxiety, and/or self-harm behaviors. There was mixed evidence for temporal relations, but study designs and a lack of rigor precluded inferences of causal relations. Our study does not support meat avoidance as a strategy to benefit psychological health.