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Thomas Cox
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96. FATS AND f A D S I N E A T I N G PORK MISS CAMPBELL: Mr. Chairman and Mmbers of the Reciprocal Meat Conference: It i s a r e a l pleasure t o be a p a r t of your program.

1 96. FATS AND f A D S I N E A T I N G PORK MISS CAMPBELL: Mr. Chairman and Mmbers of the Reciprocal Meat Conference: It i s a r e a l pleasure t o be a p a r t of your program. I did not r e a l i z e t h a t I was going t o be the only lady taking part i n the program and commentin@;on fats and fads i n eating pork. I am not doing it e n t i r e l y from a feminine viewpoint. I am considering it p r i n c i p a l l y from the viewpoint of a n u t r i t i o n i s t, and I a m a l s o r e f e r r i n g p r i n c i p a l l y t o t h e work of the National Live Stock and %at Board and i t s research program. I w i l l begin the discussion with the mention of f a t s and misconceptions i n connection wlth pork, and then conclude with a review of the value of pork and lard and f a t i n the d i e t, For many years there has been an unconfirmed idea that pork i s l e s s d i g e s t i b l e than other E a t s, that its h e p i n g q u a l i t y is limited, and that it i s high i n calories and therefore fattening. BeC6USe of these f a c t o r s, t h e erroneous idea developed t h a t pork should not be fed t o young babies ; that senior c i t i z e n s and calorie -conscious individuals should d e f i n i t e l y l i m i t the amount of' pork i n t h e i r meals, Its use i n the postoperative d i e t has been frequently r e e t r i c t e d, l a r g e l y based on these ideas. The f e a r of t r i c h i n o s i s has a l s o accounted f o r 60m prejudice against pork. Definitely we need more basic information on the subject of digestibility. W e need it on the subject of the d i g e s t i b i l i t y of a l l foods, including pork. Probably, too, a c l e a r e r d e f i n i t i o n of the term d i g e s t i b i l i t y i s needed. What i s d i g e s t i b i l i t y? Is it the length of time t h a t a food i s i n the stomach o r i n the g a s t r o - i n t e s t i n a l t r a c t, o r is it the time when a food is broken down and the amino acids appear i n the blood stream and a r e ready f o r u t i l i z a t i o n? Actually, pork when consumed with t h e f a t trimmed i s digested a l i t t l e more slowly than other meats. According t o Hawkins' d i g e s t i b i l i t y studies the length of t i m e that pork i s i n a rapid stomach i a two hour6 and forty-five minutes compared with beef two hours and t h i r t y - f i v e minutes. So t h a t it i s a c t u a l l y i n the stomach only t e n minutes longer. Vegetables are i n t h i s type of stomach two hours, whereas cake i s i n t h e stomach three hours and two minutes. So t h e statement is made t h a t pork is not d i g e s t i b l e o r that it i s slowly digested, but when you compare i t with certain other foods on t h i s basis it is not t r u e. I n c e r t a i n cases t h i s slower emptying time of t h e stomach may be desirable. It c e r t a i n l y makes pork a more s a t i s f y i n g food. It i s possible that d i g e s t i b i l i t y and t h e satiating value of food is s o m times confused.

97. According t o statements made by a u t h o r i t i e s in the f i e l d, f a t i s a6 w e l l digested as carbohydrate and protein and possibly even b e t t e r digested.

2 97. According t o statements made by a u t h o r i t i e s in the f i e l d, f a t i s a6 w e l l digested as carbohydrate and protein and possibly even b e t t e r digested. The v a r i a b i l i t y that is available i n the calorie value of pork I think is an important consideration. The f a c t t h a t one can have a trimmed product which i s r e l a t i v e l y low i n c a l o r i e s and c e r t a i n l y comparable with other meat i n calorie value o r if desirable the f a t trimming can be i n cluded i n the d i e t, so t h a t it i s a valuable food f o r the person who wants t o gain weight. Pork has t h i s v a r i a b i l i t y probably greater than any other meat. Pork today, as m had evidence in t h e previous t a l k i s markedly d i f f e r e n t than the product was 30 o r 40 years ago. You men i n the meat merchandising f i e l d have contributed much t o improved packing, merchandising and d i s t r i b u t i o n, and through your educational work i n giving the colrs u m r the type of product she wants. The pork, of course, i s from leaner, meatier hogs, showing l e e s f a t. Actually, i n addition t o the f a c t t h a t t h e pork on the market i s leaner, many weight-conscious individuals are trimming the excess fat. A t the present tie an extensive study i s being undertaken a t Oklahoma A. and M. College on the protein, f a t and calorie value of pork as well as of beef and lamb, It is expected t h a t a t the concluaion of t h i s study we w i l l have information on the a c t u a l ca3orie value of meat as consumd. h c h of the erroneous information t h a t has been d i s t r i b u t e d has been based on t h e f a c t that we have not had studies on the lean portion only of a pork chop, The c a l o r i e value o r the protein value i n previous data have included the f a t trimming of a pork l o i n mast, f o r instance, o r a pork chop. But this study w i l l bring u8 t h e l a t e s t data and should be valuable i n publications used widely, including the Department of Agriculture iflormation and c o n 8 m r information. We frequently c r i t i c i z e d i e t booklets t h a t give a high c a l o r i e value f o r pork but there i s n ' t any data on lean pork only. I a l s o should l i k e t o mention b r i e f l y a l i t t l e about pork i n t h e weight control diet. For a long time t h e tendency was t o think that the b e s t t y s of reducing d i e t was one t h a t wa.6 high i n protein. Now we a r e maintaining the high protein l e v e l but a l s o a moderate amount of f a t in the d i e t has been found t o be very s a t i s f a c t o r y as f a r a8 weight reduction i s concerned. One of the outstanding studies i s t h a t being done by D r. Charlotte Young, of Cornell University. She ha6 found t h a t by including a moderate amount of f a t in the weight reduction d i e t it i S more satisfying, and a p r s o n i s able t o s t a y on i t u n t i l the desired weight loss has been obtained. She has given 50 per cent of the c a l o r i e s from f a t i n her d i e t and has used it on both men and women a t Cornell and found it very s a t i s f a c t o r y. We will have t o check with Jerry Wanderstock on the d e t a i l s, I guess. But I do think that t h i s d i e t i s one t h a t the meat industry should be highly interested i n, because some of the d i e t s i n the past have limited f a t so considerably t h a t only lean meat has been recommended and available. Another reason t h a t pork i s p a r t i c u l a r l y good i n the weight reduction d i e t if3 because it supplies thiamine and, of course, energy t h a t is needed during t h i s period of weight reduction.

3 98. It m i g h t be said that a t the present time pork i s being fed t o young babies. Research has indicated that it is a food that can be digested and it is a d e s i m b l e food f o r young babies. It is popular with young children and an i d e a l food f o r teenagers. During the prenatal p e r i o d when n u t r i t i v e needs are increased, pork is highly recommended as a source of protein, B vitamins, i r o n and phosphorus. Any discuseion of pork, of course, must emphasize the importance of proper and thorough cookery. When pork is cooked t o the well done stage there w i l l be no danger of t r i c h i n o s i s o r toxoplasmoeis. Unfortunately, misleading a r t i c l e s on t r i c h i n o s i s have appeared in the newspapers and magazines and they have tended t o reduce the consumption of perk. Ale0 an isolated case of t r i c h i n o s i s i s frequently given widesprerd publicity. From our clipping service gome times we w i l l receive dozens of clippings on one i s o l a t e d incident of t r i c h i n o s i s. It i s SD. indication of t h e p u b l i c i t y appeal that this type of thing s e e m t o have. But undoutedly the PrOgRSS that i s being made in the radiation of' pork i s going t o be the solution of this major problem f o r the swine industry. Recently i n the Journal of the American W d i c a l Association there was a report r e l a t i n g the disease, toxoplasmosis, t o the consumption of underdone pork. You probably heard about t h i s. Taxoplasmosis has no fixed incubation period, however, and it is not possible t o t r a c e a mas8 outbreak t o t h e consumption of food a t a cormon meal. The incidence of' t h i s disease, according t o t h i s a r t i c l e i n the AMA Journal, i s said t o be from 30 t o 70 per cent of the populat i o n f r o m t h e ages of 40 t o 60 years. Like t r i c h i n o s i s, it can be cont r a c t e d from e a t i n g under-cooked infected pork. Nearly every caee of t r i c h i n e l l a i e contracted from pork, However, there seem t o be other source6 of toxoplasmosis. According t o D r. Jensen, a t S w i f t and Company, with whom I have discussed this briefly, again m c h moxe publicity is being given t o the condition. A l s o it i s not as serious a6 has been estimated by t h i s part i c u l a r a r t i c l e, and emphasis ehould be placed on the f a c t that it is possible t o contract t h i s infection in many ways other than consuming under-cooked pork. This disease o r condition i s one that needs f u r t h e r research, and it is another reason t h a t we should continually emphaeize the i m portance of cooking pork t o the well-done stage, since any danger would then be overcorn. A t the present t i m e our No. 1 health problem which ti3 very BigIIifiCantly related t o d i e t it i s the No. 1 health problem particul a r l y in the middle age man i e atherosclerosis. Here again d i e t, and f a t p a r t i c u l a r l y, i s frequently implicated. As you know, t h i s disease is charactertzed by an accumulation of a choleeterol-containing substance in t h e arteries which eventually may cause blocking and reduced circul a t i o n and quite often fatality. Researchers throughout the country are working on the cause of t h i s accumulation and methods of dislodging it I am going t o dwell p a r t i c u l a r l y on the projects that the Board if? interested i n. Another problem in connection w i t h t h i s condition l a the l e v e l of the cholesterol which is c i r c u l a t i n g i n the blood and its r e l a t i o n t o

4 99. Several experimental animals are being used i n these studies including the chick, the rat, the guinea pig, the dog and the monkey. One theory of the disease is that protein o r c e r t a i n e s s e n t i a l amino acid6, part i c u l a r l y the ones that contain sulfur, m y prevent this accumulation in the arteries. Many believe that fat i s implicated and that t h i s disease m y be the result of too much fat. Another theory i s that it is the type of f a t rather than the amount of' f a t in the diet. Some believe t h a t hard fats, such as the hydrogenated fats, may poseibly be more aamsging than s o f t f a t s such as lard and o i l s. However, several researchers are concentrating on the r o l e of f a t and I should l i k e t o r e f e r t o t h e i r work p a r t i c u l a r l y today. diet. Dr. Holman, of t h e Hormel I n s t i t u t e, ha6 indicated that when there is a high cholesterol l e v e l in the diet, the intake of e s s e n t i a l f a t t y acids may help prevent any dmege. Be hat3 found that a high blood cholest e r o l l e v e l seems t o increase the need f o r t h e e s s e n t i a l fatty acids. of course, lard i s one of our important source8 of e s s e n t i a l f a t t y acids and may, therefore, possibly offer 8 0 e protective value. Dr. Kummerow, of the University of Illinois, has emphasized the f a c t that cholesterol is manufactured i n t h e body and that the amount conmmd normally i n food i s not a hazard, However, cholesterol i n the body may be manufactured by d i e t a r y carbohydrate. Dr. Kumnerow has investigated the p o s s i b i l i t y t h a t a high protein d i e t may reduce choleeterol synthesis i n the body. He has reported that hydrogenation of fats r e s u l t s i n the formation of trans-acid forme which m y not be as r e a d i l y metabolized a8 lard and n a t u r a l fats. These trans-acid forms have developed when hydrogenated fats have appeared i n t h e a t h e r o s c l e r o t i c t i s s u e s which they have examined i n persons that have died of coronary disease. They have found that these trans-acid forms are present i n about 10 per cent. They make up about 10 per cent of the fat. It i s possible then that more of t h e hydrogenated fats may be retained i n the bcdy and be deposited i n the a r t e r i e s and, therefore, be a hazard t o health. He has emphasized, too, that the e s s e n t i a l f a t t y acids which are present i n animal f a t s cannot be synthesized by the body, that they must be present in the food, and if they are e s s e n t i a l then the f a c t that they cannot be synthesized i s an important reason f o r including them i n the diet. Dr. Stare is another researcher who has done a g r e a t deal of work i n t h i s f i e l d, and he has developed atherosclerosis i n monkeys by feeding a diet which contained i n s u f f i c i e n t amounts of sulfur-containing amino acids. After developing this condition i n the monkey he ha6 operated on i t and removed part of the artery, and he is now feeding it a 60called protective d i e t o r a curative type of d i e t t o see if he can c l e a r up the lesions i n the a r t e r y that s t i l l exist. After developing the cond i t i o n he has removed some of the tlsaue,and he is now feeding a curative d i e t t o 6ee i f the remaining lesions can be cleared up through d i e t. D r, Stare ha6 emphasized the role of c e r t a i n t y p s of f a t in increasing the l e v e l of blood cholesterol. His report Indicated t h a t hydrogenated f a t may be more damaging than s o f t fats, such a8 lard and o i l s. D r. Stare has reported that he has given injections of f a t emulsions t o p a t i e n t s who have cardiovascular disease and abnormally high blood f a t levels. Although the blood l e v e l s were slower i n returning t o normal

5 these p a t i e n t s that had high blood f a t l e v e l s after being given infusions of f a t, they returned t o n o m 1 event!rally and he f i n d s t h a t he i s unable t o explain why the f a t infusions resulted i n a lower blood f a t l e v e l after they were given these injections of f a t emulsions. In one case he found a decrease of 60 E]er cent i n the blood f a t l e v e l i n seven days. After giving an bf'usion of f a t t o the patient who had a very high f a t l e v e l there was a drop of 60 per cent in t h e blood fat l e v e l in aeven days, D r. Stare reported t h i s j u s t recently a t the Anericw Chemical Society meeting i n New York. D r. Stare has continually emphasized, as have other researchers, t h e importance of maintaining normal weight and the r o l e of exercise. In addition he believes t h a t the B vitamins, choline and pyridoxine, may play a role i n t h i s condition, The indications are t h a t we need more information on the subject of pyridoxine, and D r. Schweigert, of the American Meat I n s t i t u t e Foundat i o n, is one of the researchers who is working i n t h i s f i e l d. On the positive side as far as meat and f a t i n the d i e t are concerned, we are g e t t i n g more and more evidence of the value of the e s s e n t i a l f a t t y acids i n human n u t r i t i o n. D r. Hansen, at the University of Texas, Medical Branch, i s continuing t o study the role of e s s e n t i a l f a t t y acids i n the health of skin. He has recently reported that more c a l o r i e s may be needed on a low f a t d,iet than one which contains 8 moderate amount of f a t. Thus the moderate f a t l e v e l being recommended by D r. Young and others seems logical. Studies on exprimental animals have indicated t h a t unsaturated fats, such a8 l a r d and O i l s, may have a protective e f f e c t when animals a r e exposed t o radiation. This is from some of t h e work t h a t D r. Duo and h i s group a t California have done, Reports from the American %at I n s t i t u t e Foundation and from D r. Doty and h i s group suggest that f a t may have a protective e f f e c t against the development of off-odor8 during the i r r a d i a t i o n of mat, and may help t o explain why there i s less obgection and organoleptic changes i n pork than i n beef, It aeems that f a t supplies in many parts of the world are extremely limited. Few s t u d i e s of fat-deficiency conditions have been made, but we know t h a t during wartime i n c e r t a i n parts of the world they r e ported inefficiency of workers, and that there was a craving f o r f a t i n areas where people were seriously r e s t r i c t e d i n the amount of f a t available, and skin conditions, too, occurred widely. Whether t h i s was e n t i r e l y due t o the fat-deficiency, of course, i a not d e f i n i t e. D r. Stare has reported that, i n contrast t o the f a t deficiency and the lack of f a t i n many p a r t s of the world, i n the United States t h e per capita f a t intake has increased from 135 t o 148 gram6 p r day from 1935 t o T h i s may be p a r t i a l l y due t o increased consumption of meat, milk and eggs, and a decrease i n c e r e a l and potato consumption. The average American d i e t supplies from 36 t o 46 per cent of the t o t a l c a l o r i e s in

6 101 the form of fat. Of t h i s amount, approximately 70 per cent i s from animal sources and 30 per cent i s from vegetable sources. In general f a t increases the p a l a t a b i l i t y of intake of n u t r i t i o u s food. It givea value t o a meal. f a t s t a y s with a person longer than one which supplies be due t o i t s slower d i g e s t i b i l i t y, but although it i s it i s almost completely digested. food and insures t h e A mal which contains less f a t. This may digested more slowly, One of the advantages, too, of lard i s that it has a lower melting point. Its melting point i s c l o s e r t o that of body temperature, which explains why it i8 probably more r e a d i l y emulsified i n the digestive process, and i t s over-all d i g e s t i b i l i t y is s m t h i a g t h a t is very important. Researchers recently have warned against the dangers of a too low f a t d i e t. Many people are recommending a low fat, low cholesterol type of d i e t, and yet D r. I m i n e Page, who i s one of our a t s t a n d i n g a u t h o r i t i e s on cardiovascular disease, has said that he has seen symptoms such as stomach and i n t e s t i n a l upsets, depression and I r r i t a b i l i t y follow 6evere f a t res t r i c t i o n. This i s the type of fat r e s t r i c t i o n that many people undertake i n cases of heart disease. The trend toward reduced f a t and lower protein intake may produce undesirable n u t r i t i o n a l deficiencies. As yet the significsnce of R higher blood cholesterol l e v e l i s not b o r n. Whether a higher l e v e l i n the blood may man that less cholesterol i s deposited i n the arteries has not ss yet been determined. Pork has long been known t o be an important aource of thiamine and, of course, it is recognized as one of our o u t s t a n d i w sources of t h i s inportant B vitamin. Recently another f a c t o r has been discovered i n pork under the d i r e c t i o n of Dr. ElvehJem, a t the University of Wisconsin. Research has indicated that pork muscle protein has a protective e f f e c t i n animals that have been exposed t o stress. This protective f a c t o r i n pork has not a6 yet been i d e n t i f i e d. Pork i e superior t o casein in t h i s connection. Animals fed a8 high a8 42 per cent pork protein survived t h e 60-day period wlzerear, basal animals fed casein died af'ter an average of 30 days. Pork muscle ha8 a favorable e f f e c t on the l i v e r e n z p system which may be a l t e r e d during hypothyroidism. More research i s needed t o isolate t h i s protective f a c t o r i n pork and investigation of its action. W e all know that pork l i v e r is an outstanding source of iron and t h a t a c t u a l l y it contains almost three times as much as beef l i v e r and about one and two-thirds tims as much as t h e more expensive calf l i v e r. I think that n u t r i t i o n i s t s and d i e t i t i a n s mld do well t o emphasize more the importance of pork l i v e r as a n u t r i t i o u s food. In summsry, the role of pork and f a t i n n u t r i t i o n i s very mch in the limelight today. Further research i n t o the problem of atherosc l e r o s i s with regard t o d i e t s, and f a t p a r t i c u l a r l y, may a c t u a l l y strenghten t h e r o l e of high q u a l i t y protein foods such a8 pork which a l s o provides other d i e t a r y e s s e n t i a l s. More and more research i s needed a s t o the role of pork as the source of e s s e n t i a l unsaturated f a t t y acids and of lard,

7 102. i t s by-product. Many of the fads and misconceptions which formerly existed with regard t o pork have d e f i n i t e l y been overcow, but education i s con- t i n u a l l y needed t o correct and counteract much of the misinformation about pork and f a t i n general, More emphasis should be placed on the positive value of f a t as an e s s e n t i a l nutrient and as our most e f f i c i e n t source of energy, I should a l s o l i k e t o refer i n closing t o an a r t i c l e concerning the problem of pork and f a t i n coronary disease which appeared i n the Journal of the American Medical Association which is called, "Eat, Drink and Be Coronary." It gives a l i t t l e humor t o t h e s i t u a t i o n, and it r e f e r s t o an Englishman who has been d i e t i n g t o cut down his weight. Then he reads an a r t i c l e saying t h a t fat i s not r e a l l y the menaoe but cholesterol. It goes on t o s a y : "He has never head of cholesterol which sounds t o him l i k e some kind of motor o i l. This i8 t h e unhappy difference between himself and the more progressive American hypochondriac. Instead of shuffling around hopefully eating nothing, t h e American sweeps through the door of h i s doctor's o f f i c e, bears his a m, and demands, 'Say, doc, take my blood cholesterol, w i l l you, and it it i s over 220 milligrams, boy, am I f o r the high jump. "The British d i e t e r has t o read down the column t o discover t h a t, whatever cholesterol is, egg8 are f u l l of it. Despair a t l a s t overcorns h i m. The boiled egg i 8 h i s last connection with the world of sane gastronomy, and now h i s breadfast looks as dangerous as a hand grenade. He breaks down and weeps and i s s h o r t l y afterwards taken by ambulance t o a psychiatric h o s p i t a l as a case of anorexia nervosa. "It is unsgorting of Fleet s t r e e t never t o mention t h e two most important f a c t s about heart disease that coronary thrombosis i s uncommon i n Italy and alcohol has an excellent pharmaceutical e f f e c t on the coronary arteries. So i f you remain permanently b o t t l e d i n a v i a l i n Sorento you won't have anything t o worry about a8 long as you don't read the papers." -- Thank you very much. e wish t o thank you f o r your appearance CHAIRMAN PEARSON: W on our program, Rita, and we c e r t a i n l y enjoyed your t a l k. The Chairman of the Pork Carcass Evaluation Committee reminds m t h a t we have one o t h e r person l i s t e d on the program t o speak and unfortunately t h a t p r s o n cannot be present. As a r e s u l t of t h i s, we have a s u b s t i t u t i o n f o r t h i s speaker and a s u b s t i t u t i o n of the subject. Our next speaker w i l l discuss the preparation and freezing of pork carcasses f o r demonstration purposes. To present the subject we have D r. L. E. Walters of Oklahoma A. and M. Lowell. ########

N O W JACOBSON. Iowa S t a t e University

N O W JACOBSON. Iowa S t a t e University THE CONTROVERSY OVER THE RELATIONSHIP OF ANIMAL FAT TO HEART DISEASE* N O W JACOBSON Iowa S t a t e University Much has been w r i t t e n on t h e r e l a t i o n s h i p o f d i e t t o heart disease