Protein

Meat and pellagra. 

Pellagra is a disease which occurs in areas where the diet is lacking in fresh meats, milk, eggs, and leafy vegetables. An adequate diet is the only effective method of prevention and cure of this disease. In early studies of this disease the cause was attributed to lack of sufficient protein of good biological value. The preventive action of fresh beef, which furnishes excellent protein, no doubt was responsible for this conclusion drawn by the late Dr. Goldberger and his co-workers. 

Further study by these workers in which a larger intake of protein in the form of casein failed completely to prevent the disease demonstrated that the potency of the beef was not due entirely to its protein. The results of such experiments have been interpreted as indicating that an unrecognized dietary essential is concerned with the prevention of pellagra. 

This factor, designated as P-P, according to these workers, might be effective with little or possibly no cooperation from the protein factor. The pellagra-preventive activity of yeast extract gave further evidence of the existence of this factor P-P. [65]  

Later studies associated pellagra-preventive factor P-P with vitamin B and revealed the multiple nature of vitamin B. Factor P-P, now designated vitamin G of the vitamin B complex, is contained in dried lean beef. Its presence in dried beefsteak and liver also has been demonstrated. The work of Hoagland and Snider has shown its presence in several dried tissues of beef, pork, and lamb. Eecent work by Sherman and Derbigny1  points to the possibility that both protein shortage and vitamin G deficiency may be concerned in the development of pellagra-like symptoms. They say: "In so far as the symptoms of shortage of vitamin G are regarded as pellagralike, such a vitamin theory of the disease should not preclude recognition of the possibility that the protein supply may also have a significant bearing on the pellagra problem." 

Day2  reports determinations of vitamin G in fresh tissues of beef and veal. This work found beef heart to be three times as potent as beef round steak; beef kidney 8-10 times; beef liver 10 times; veal round steak showed slightly higher concentration of vitamin G than beef round, and veal liver and kidney were about the same as beef kidney. 

From this study, as well as others, the potency of the glandular organs is shown to be higher in vitamin G content than the muscle tissues. When a diet consisting largely of salt pork and starchy foods is changed to one in which lean meats, milk and legumes are abundant, pellagra disappears.

Omnivorous Mankind By MARY PASCOE HUDDLESON 

Editor, Journal of the American Dietetic Association 

Ideal diet neither one-sided nor weird, despite proponents of various “fads”, expert contends. ... Menu for adequate amounts of all “protective” Meat is held essential for providing . . How explorers lived five years in the Arctic on exclusive diet of foods. readily convertible proteins. meat and returned in good health. . finds that “man is an omnivorous animal and subsists on the most extraordinary food combination”’. 

Let us consider meat from the point of view of its place in the diet of so-called normal or healthy persons. Meat is a tasty, agreeable food to many, and constitutes an important source of protein, an essential substance in the building and repairing of body tissue. Further than this, the proteins of meat, fish and other animal foods such as eggs, milk and cheese, are of high quality and can be readily converted into body tissue. 

An overwhelming array of evidence has been offered to show the ill effects of a diet too low in protein. We all know the type (usually female) who boasts of taking nothing but coffee, a slice of toast and fruit juice for breakfast, and selects a luncheon or dinner similar to this: fruit cup; vegetable plate consisting of three or four vegetables; a large green salad with French dressing; a fruit ice; and then more coffee. These foods are eaten with a virtuous feeling that such edibles are good for you. And so they are, in sensible amounts and when combined with sufficient of the animal sources of protein —meat, eggs, cheese. 

Man, while a mammal, is neither a rabbit nor a cow. It is difficult for him, yet comparatively easy for the cow, to get sufficient protein from vegetable food. The rabbit-like eater may go on for months without showing serious evidences of any lack. But probably many a languid, listless lady might perk up and change her mental outlook if she would only let herself go with a goodly cut of rare roast beef or a juicy steak. Not only is the non-meat eater apt to be short of protein (particularly if no milk, cheese or eggs enter into the diet), but listlessness and susceptibility to fatigue, suggestive of secondary anemia, can result when a diet is deficient in iron. Meat, as well as being a valuable source of protein, is a good source of iron. 

 Of all the dietetically inspired battles that have raged above the rattle of the tea cups, probably the one with the vegetarians on the one side and the meat-eaters on the other, has been the most heated. At times the disturbance raised reminds us of what the diet-faddist claims will happen if these two types of foods (carbohydrate rich and protein rich) get mixed up in the human stomach—an explosion! Writing m the Journal of the American Medical Association some time ago, Dr. Martin E. Rehfuss said: ‘Man is an omnivorous animal. He subsists equally well on the high-protein dietary (meat— fish) of the arctics, the high-carbohydrates regimen of the tropics, and the most extraordinary food combinations of the temperate zones.” On the surface this is true. Man seems to be more ‘adaptable than any other animal to a variety of situations. 

Perhaps the strongest argument in favor of an exclusive diet was presented in the observations of Dr. Eugene F. Du Bois of Bellevue Hospital on the explorers Stefansson and Anderson. Mr. Stefansson gave in Harpers Magazine a popular account of his adventures in diet. After living in the Arctic for a total of more than five years, exclusively on meat (fish and water), Mr. Stefansson returned to so-called civilization to tell of his good physical condition on such a diet. His views were looked upon with some skepticism. 

Finally a series of experiments were conducted upon Stefansson and Anderson at Bellevue Hospital, New York City. The men lived upon an exclusive meat diet for a little over a year. The meat consisted of beef, lamb, veal, pork and chicken and the portions of the animal used included the muscle, liver, kidney, brain, bone marrow, bacon and fat. The meat was taken for the most part only lightly cooked, except for the bone marrow which was eaten raw. At the end of the year the physical condition of both men was as good as at the beginning. There was no rise in their blood pressure; there was no evidence of kidney irritation or damage; no constipation developed nor any other obvious ill effects from the prolonged use of an exclusive meat diet. It is significant, however, that an exclusive meat diet, in order to be complete or adequate consists not only of flesh meat with a goodly portion of fat, but includes portions of the glandular structures such as kidney and liver as well. Furthermore, some of the meat eaten should be very lightly cooked, or practically raw. In the case of Stefansson and Anderson, the bone marrow was eaten raw, and they followed the Eskimo habit of eating fish bones and chewing rib ends, thus doubtless securing a fair amount of calcium. 

* * * 

The chief importance of this experiment was not to encourage people to live on an exclusive meat diet, since this would be economically expensive and socially inconvenient. It did serve, however, to show that meat is probably not the cause of all the evil effects that have been ascribed to it. In his series of articles, Stefansson himself concludes that “you could live on meat if you wanted to but there is no driving reason that you should”. 

But in the amounts usually taken in the American diet, meat serves its purpose as a valuable food; and in the light of reputable evidence there is little to be said against its place in the diet of normal people. Further than this, much that has been said against meat, to the effect that it causes or aggravates certain diseased conditions, seems to be open to question. Chief among the sins chalked up against meat have been the accusation that it is a disturbing or promoting factor in rheumatoid arthritis, kidney disease, Bright’s disease and high blood pressure. This sentiment is gradually being dispelled. 

Recent and authoritative medical writers now place little reliance on a low protein (or low meat) diet in arthritis. In contrast to the supposition that a high protein diet is productive of kidney damage, it is believed by many that a diet low in protein may damage practically all the body tissue, since protein food is essential for building and repairing body tissue. The dietary treatment, today, of chronic Bright’s disease of the kidney, includes sufficient protein food of good quality. If the diet in this disease is too low in protein foods, for example meat, it is said that the anemia so commonly associated with it comes on more rapidly. 

Dr. Clifford J. Barborka in “Treatment by Diet,” lists foods useful for their blood-building qualities as follows: meats (liver, kidney, beef, chicken gizzard, lamb); eggs, fruits (apricot, peach, prune, raisin) ; and vegeta- bles (spinach, beet greens, letuce). Cereals, dairy products and breadstuffs, according to Drs. Whipple and Robsheit-Robbins, have the minimum value, while liver is the most potent factor in hemoglobin production. .. . 

While the average American diet is believed not to be deficient in iron or protein, yet the many vague symptoms commonly attributed to the Spring, if it happens to be that time of the year, may be due to insufficient protein of good quality, or to insufficient iron. 

The ideal diet is one that contains adequate amounts of all the protective foods — milk and its products, eggs, leafy vegetables, fresh fruits, and meat. It is neither one-sided nor weird, and best of all it can be one which may be eaten with enjoyment as well as benefit to health. 

—Permission, This Week—N. Y. Herald-Tribune

Introduction. 

With the increasing human activities in circumpolar areas in recent years, the problem of an adequate and physiologically suitable ration with high caloric density has been the subject for much dispute among physiologists and nutritionists. Although a high protein diet has been successfully used by Eskimos and arctic travellers for generations, both as trail diet and emergency rations, there has been a tendency in recent years to emphasize the desirability of an all-carbohydrate ration ( Mellinger, 1948, Roth, 1948, Dyme, 1950). One of the main arguments in favor of the carbohydrate ration has been its antiketogenic effect, assuming harmful effect of slight ketosis even during the short periods of survival in question under arctic conditions. 

With reference to these questions a study was designed, the purpose of which was to consider a high-carbohydrate versus a high-protein diet, with reference to physiological adequacy and an evaluation of the physiological and clinical significance of ketosis under strenuous arctic field conditions during midwinter in Alaska. 

4. Discussion. 

It is clearly realized that the determination of ketone bodies is subject to considerable inaccuracy. However, the reported data indicate that under the conditions of the test the excretion of urinary acetone in the meat group never exceeded 1 g per day. The highest figure recorded was 8 66 mg which is a very small amount. 

According to Peters and Van Slyke (1946), ketones are regularly found in the urine of healthy persons leading a normal life. Van Slyke found as much as 280 mg ketones per 1000 ml urine. Others have reported figures between 7 and 125 mg daily. 

Under conditions such as total starvation when all energy is derived from protein and fat, the production of ketone bodies by the liver is accelerated and the excretion of ketones in the urine increases. In normal adults the appearance of gross ketonuria, according to Peters and Van Slyke (1946), does not reach its height until 3 to 5 days of the fast have elapsed. As starvation proceeds ketosis gradually diminishes. He states that in the normal male, ketosis of starvation does not reach serious proportions because sufficient carbohydrate is derived from protein and oxidized, and the levels of blood ketones are not high enough to tax severely the mechanism for the preservation of acid-base equilibrium. In one subject about 6 g of ii-hydroxybutyric acid were excreted daily in the urine for the last two weeks of a 31-day fast. In diabetic acidosis ketonuria may reach values 10 times higher than this. 

Compared with these figures the amounts of acetones excreted in the urine in our subjects on the meat ration are insignificant, and it appears that this slight ketonuria observed under these conditions for the periods considered likely as the duration of a survival situation would have no appreciably harmful effect. 

Exercise greatly increases the ketosis, and a 10-mile walk in the morning without breakfast will produce distinct ketonuria in a healthy person who otherwise is living on a normal diet (Courtice and Douglas, 1936). 

A number of evidences indicate a mechanism of adaptation to ketosis. In our Eskimo studies it is observed that the degree of ketonuria is less than what is normally observed in Whites on a similar diet. On the other hand, an Eskimo soldier who had lived for several months on the normal Army mess rations excreted the same amounts of acetone as the normal white soldiers when given a "ketogenic" diet. In the subjects studied by McClellan and DuBois (1930) the ketonuria diminished after several months on a carbohydrate-free diet. 

Deuel and Oulick (1932) have demonstrated that ketosis develops more rapidly and attains greater intensity in women than in men. 

It has been repeatedly observed that ketosis frequently occurs under strenuous field conditions regardless of the diet, and Sargent and Consolazio (1951) showed that the ketosis is reduced when the same subject undergoes repeated field tests, indicating some evidence of adaptation. 

In an Arctic bivouac at Fort Churchill the approximate caloric expenditure was 4000 calories per day. The caloric intake was about 3600. Under these conditions all the men showed trace quantities of urinary ketones almost every day, starting on the third day in the bivouac (Molnar et al., 1942). 

Of the great variety of physical fitness tests (Cureton, 1947), the Treadmill Test was selected for practical reasons. It should be emphasized, however, that physical fitness is exceedingly difficult to evaluate, not only because the meaning of physical fitness is far from clear, but also because the result of the test is greatly dependent upon a number of factors beyond the control of the observer. 

In all cases we observed an improvement at the end of the field phase, most marked in the carbohydrate group, associated with approximately 10-pound weight loss (7.5 %). 

It should be noted that the subjects had been living on a caloric deficit of the order of 2000 calories a day, and performing daily route marches of 10 miles. 

In the case of untrained personnel in poor physical condition, one would expect an improvement in physical fitness during the field phase. Our subjects, however, were all well trained and in excellent physical condition at the onset of the experiment. The factor of physical training therefore can hardly explain the difference in the physical fitness scores. 

On the other hand, it appears that the weight loss may be the most important factor in explaining the observed difference. The subjects started off probably slightly overweight and the loss of 7 per cent of their body weight would tend to increase their physical performance, since there is less weight to carry during the exercise. This is in conformity with general experience under similar conditions. It is observed that the carbohydrate group, which had the greatest weight loss, also showed the greatest improvement of physical fitness scores. The purpose of the experimental phase was to study the effect of the experimental diet on various physiological functions as compared with the levels during the normal conditions in the standardization phase. The results indicate the following effect: Both in the carbohydrate group and in the meat group, there was an increase of the physical fitness scores, most pronounced in the carbohydrate group. The basal heat production was 13 per cent higher at the end of the experimental phase than during the standardization phase in the meat group, while a reduction of 7 per cent occurred in the carbohydrate group. This difference is probably due to the specific dynamic action of protein. During the experimental phase the meat group consumed 300 ml more fluid per day than the carbohydrate group. While all subjects in the meat group were in a positive nitrogen balance, the subjects in the carbohydrate group showed a negative balance of 6.3 g on an average. Ketonuria occurred in all meat subjects and in three of the carbohydrate subjects. 

During the field phase the factor of climatic stress was added to the experimental conditions, and the following results were obtained: 

No significant difference was observed in the physical performance of the subject on the meat ration, the carbohydrate ration, or on the meat-and-carbohydrate ration during the actual field phase. The physical fitness scores were improved in all three groups at the end of the field phase, and this improvement was greatest in the carbohydrate group which also had the greatest weight loss. The psychiatric evaluation revealed no distinct differences between the three groups. There was no significant deterioration in morale, but an increase in carelessness, irritability and desire to sleep which occurred in all three groups. The weight loss was 7.0 per cent in the meat group, 7.5 per cent in the carbohydrate group, and 6 per cent in the group receiving both meat and carbohydrate. There was an increase in the basal heat production of 9 per cent in the meat group and 7 per cent in the meat-carbohydrate group, while the carbohydrate group showed a reduction of 7 per cent in the BMR. The water consumption was 1500 ml in the meat group, 850 ml in the carbohydrate group, and 1200 ml in the meat-carbohydrate group. All three groups showed negative nitrogen balance, which was most pronounced in the carbohydrate group, where it was approximately 7 g, as against approximately 2 g in the meat group. Ketonuria occurred in all three groups, most pronounced in the meat group. 

On the basis of these findings, and in view of the fact that water supply, as a rule, does not present any problem in the Arctic, it may be concluded that the carbohydrate ration offered no significant advantage under conditions of arctic survival as stimulated in the present study. In terms of heat production and nitrogen balance, the high meat ration is preferable. It is evident from this study that under survival conditions, which necessitate caloric expenditure, between 2500 and 3000 calories per man per day, including travel of approximately 10 miles a day, 1000 calories per man per day is sufficient for a period of at least 10 days. 

It would therefore seem logical that survival rations developed for arctic use should consist of protein, fat, and carbohydrate in proportions which would serve to utilize the specific dynamic action of a high protein diet, the high caloric density of fat, and the physiological advantages of carbohydrates. Protein-fat rations with high caloric density such as various types of pemmican, have already been successfully used for more than half a century by arctic travellers. 

It would appear advisable to base future arctic survival rations on the principle of a high meat-fat ration as the main meal of the day prepared in the evening, and an all-carbohydrate component of the ration to be consumed in the middle of the day while on the trail. 

5. Summary and Conclusions. 

In a series of laboratory experiments followed by field experiments under strenuous arctic conditions, the physiological adequacy of low caloric arctic rations have been studied in groups of normal men under conditions which necessitate travel under various arctic conditions. The rations studied contained approximately 1000 calories per man per day and consisted of an all-carbohydrate ration and a high protein-fat ration. On the basis of the presented data it may be concluded that from a physiological standpoint the all-carbohydrate ration offered no significant advantage over the high meat ration under the conditions of the study.

The Author, Richard Mackarness, was the doctor who ran Britain's first obesity and food allergy clinic. The book merges anecdotal observations from this clinic with a comprehensive review of all medical evidence throughout the world up to the mid-1970s. In the 1975 edition, this includes a historical analysis of diets from Harvey-Banting to Robert Atkins and Herman Taller, and features the work of Blake Donaldson, Vilhjalmur Stefansson and Alfred Pennington, who all promoted an Inuit-style meat-only diet. Mackarness extols the virtues of Pemmican, discusses food allergies, examines carbohydrate addiction and touches on related psychology.

Mackarness's philosophy has three main features:-

• A person's metabolism falls into one of two distinctive types, the constant-weight always-slim type, and the fatten-easily type.

• Weight gained by people in the latter group is due to an inability to break down carbohydrates fully because of a metabolic defect, and not as the public at large believe, because of weak-willed gluttony.

• Man's problems with obesity began 8,000 years ago, with the advent of cereal planting. For 4 million years before that, man was a hunter who survived by killing and eating meat, which has led to complete biological adaptation to a meat diet, but not to a cereal diet, because it is too recent.

Another example of this thinking also dates to the 1970s and comes from George Blackburn and Bruce Bistrian at Harvard Medical School. Bistrian and Blackburn developed what they called a “protein-sparing modified fast” to treat patients with obesity: 650 to 800 calories a day of nothing but lean fish, meat, and fowl. It had effectively no carbohydrates, making it a ketogenic diet, albeit a very low-calorie version. Bistrian and Blackburn prescribed the diet to thousands of patients, as Bistrian told me when I interviewed him in January 2003, and half of them lost at least forty pounds. In one 1985 publication reporting on almost seven hundred patients, the average weight loss was nearly fifty pounds in four months. The patients felt little hunger while on the diet. “They loved it,” Bistrian said. “It was an extraordinarily safe way to get large amounts of weight loss.” 

But one point that Bistrian made in our interview was critically important: If he and Blackburn had tried to balance these diets by adding, say, vegetables, whole grains, and legumes, meaning the patients would obviously be eating more calories and more carbohydrates, the diets would have failed. You’d think more calories would mean less hunger, but it would cause more. Bistrian was the first one who pointed out to me the different responses between Ancel Keys’s starvation experiment subjects—eating 1,600 calories a day and, well, starving—and the experiences of the patients he and Blackburn were working with, or Sidbury was treating, who were perfectly content consuming far fewer than 1,000 calories a day. “The proof of the pudding,” he said to me, “was in the eating.” 

Alas, Bistrian and Blackburn’s thinking, and Sidbury’s, was flawed. They were telling their patients—Sidbury’s were kids; Bistrian’s and Blackburn’s were adults—to severely restrict calories because that was what they still thought was necessary. Despite everything they knew about insulin and fat metabolism, they too couldn’t escape the trap of energy balance thinking. Because Bistrian and Blackburn were feeding their patients so few calories, this created a problem that appeared to the two researchers to be insurmountable. It had to do with maintaining the weight loss. 

For a diet to work for a lifetime, it has to be maintained for a lifetime, and for a diet to work—to get us lean, or relatively so—it has to remove or limit the cause of why we get fat. If the cause is too many calories, then a lifetime of calorie restriction at some level is necessary. If the cause is elevated insulin levels and too many carbs, then a diet that maintains insulin at a low threshold for a lifetime—carb-restricted, high in fat—is necessary. There seems no getting around it. Bistrian and Blackburn were perfectly aware of this problem. They knew that if their patients went back to eating the way they did, they’d gain the weight back. If they ate more calories but still worked to keep insulin low, they’d be restricting carbohydrates and replacing them with fat. They’d be eating what Bistrian and Blackburn thought of as an Atkins diet. And unless you believed that eating all that fat was benign—as many physicians finally do today—that was unacceptable. Bistrian said this was a primary reason he and Blackburn left the field. They had two choices, they thought: Tell their formerly fat patients to take appetite-suppressing drugs so they could spend a lifetime battling hunger on a calorie-restricted but balanced diet, or tell them to eat the Atkins/ketogenic way, to satiety of fat and protein. They considered neither to be a safe option. “All that saturated fat,” Bistrian said to me. He and Blackburn turned their attention to other things. We don’t have that luxury.

Gary Taubes. The Case for Keto: Rethinking Weight Control and the Science and Practice of Low-Carb/High-Fat Eating (Kindle Locations 1733-1734). Knopf. Kindle Edition.