Access to all articles, new health classes, discounts in our store, and more!
(Originally published in 1957)
Animal fats in the dietary provide man with a source of fatty acids that can be utilized with relatively little damage to the highly active unsaturated components natural to the species. The physiological effect of a fat or an oil depends on its chemical composition. The nutritional value of animal fats varies from species to species, and the general characteristics of a fat are peculiar to a given species. However, the sex of the animal, whether altered or unaltered, the age of the animal when altered, and the age at the time of slaughter, along with the feeding methods used in rearing the animal, including the use of chemicals in the feeds, can change the chemical characteristics of the fat.
The fat of beef contains less unsaturated fatty acid than does the fat of the lamb or pork. These meats, when properly prepared, are more effective in the treatment of conditions requiring low melting point fats than beef. Improper processing, particularly overcooking, chemically alters fat so that toxic properties may be present.
The unsaturated fatty acids of low melting point, particularly those of lamb, are most effective in the treatment of one of the commonest forms of fat disorders, simple dry skin. The higher melting point fats with less unsaturated fatty acid content are more useful as fuel to the body, and the characteristic of the subcutaneous fat of the human being can be changed by the type of fat he consumes.
● ● ●
Fats in the diet serve four major purposes. First, they supply energy for locomotion and the maintenance of bodily temperature. Second, they supply the body with depot reserves that secondarily insulate against mechanical injury, heat, and cold. Third, they provide a source of elements for a complex metabolic process. Fourth, they act as agents for the transfer of nutritional accessories.
The so-called neutral fats are glycerol esters of fatty acids. They are composed of a molecule of glycerine attached to three fatty acid radicals. Glycerine is freed from the fatty acid radical in the process of digestion by hydrolysis. On assimilation into the body, glycerine is oxidized, releasing energy in a manner similar to the utilization of carbohydrate. It is changed into phosphoglycerol. The fatty acid radicals, likewise, are oxidized with a further release of energy.
Long chain fatty acids are broken down, step by step, to the so-called C-2 fragments or acetic acid radicals. Octanoic acid, for example, is first reduced to a molecule of hexonic acid plus an acetic radical. The hexonic acid is reduced to butyric acid plus an acetic acid radical, and the butyric is reduced to two molecules of acetic acid by oxidation. The breakdown of this 8-carbon atom of fatty acids gives four acetic acid [radicals] or C-2 fragments, which in turn can be changed into two molecules of aceto-acetic acid.
Some of the fat that is consumed in excess of body requirements is deposited in the so-called fat depots. These fat supplies serve the purpose of protecting the body from mechanical injury, of insulating against heat and cold, and of acting as a source of energy in case the intake of fat in the food falls below the normal nutritional requirements. These stores are constantly changing with the metabolic picture of the individual. They provide 1000 calories per kilo when released as energy.
The acetic acid [radicals] or C-2 fragments enter into many complex chemical processes within the body, providing the building stone for the elaboration of cholesterol, acetylated amines, and many complex metabolites necessary for bodily functions. The assumed mechanism for the utilization of these fragments in the production of more highly complex radicals is known as the Krebs cycle.
The further function of dietary fats is to act as carriers for absorbed substances that are found accompanying natural fats. These substances of animal origin consist of the four fat-soluble vitamins – A, D, E, and K; certain of the animal steroids, such as the ovarian, testicular, and cortical adrenal hormones; and compound lipids, such as the phospholipids, sphingomyelins, and others. These lipids are usually metabolized in a manner similar to the simple lipids.
The simple fats differ greatly in their chemical composition and their physical properties. Physically, the fats are divided into the fats and fatty oils, depending upon whether or not they melt at 20° C. This is determined, in part, by the number of carbon atoms in the chain of the fatty acid and whether or not the chain contains double bonded carbon atom linkages. The so-called saturated fatty acids above six carbon atom chains are solid. On the other hand, the unsaturated fatty acids, including those with as many as 22 carbon atoms, are still liquid.
Depot fats vary greatly in their chemical composition, depending on the carbohydrate and fatty acid content of the ingested food. Likewise, the chemical composition of depot fats of an animal vary with the location in the body, such as in the highly active depot fat of the peri-renal tissue when compared with the fat of the buttocks. In spite of those changes that can be brought about, there appear to be certain physical characteristics of the depot fats of an animal of a given species that are specific. The fat of a hog can vary from a fatty oil, when rendered as lard, to a firm, clear white substance, depending on its feed. One would not confuse these widely variable tissues of the hog with those of the steer, which tends to store a much higher melting point fat with a greater quantity of saturated fatty acids.
These differences would be particularly evident when comparing two animals of different species on similar types of ration. Besides the effects on the composition of the fatty acids of depot fats stored in the tissue of animals, due to their rations and species, we have differences in chemical composition due to the sex of the animal. This controls not only the location of the depot deposit but to a lesser degree composition of the fat. Age, too, has a marked effect on the character of the fat. The female of the species tends to have a slightly softer fat than a male of the same age. In certain phases of the reproductive cycle, the female tends to store much more fat than at other phases. The infant, too, has a fat of considerably different composition from the mature. The castrate differs from the normally sexed. The state of nutrition is determined in part by the metabolic activity of the animal. The highly active physical animal stores less fat and utilizes its fat stores in starvation. The fat of the highly active tends to be firmer and contain less water than that in the less active. All fats contain some water. The lower the metabolic level of the individual, the more water is stored. This is well understood by the animal husbandryman who frequently places his animals on starvation rations before putting them on his fattening diet. Farmers have likewise learned that the use of certain drugs, along with inactivity and high carbohydrate feeding, will reduce metabolism and aid him in fattening the animal. Such practices frequently produce an animal with tissues that are softer but frequently less tasty than those of an animal with better metabolism.…
Besides the alteration in the composition of fats above mentioned, the care with which these food elements are stored and preserved is of great importance. Saturated fatty acids are relatively stable compounds. It is for this reason that hydrogenization of fatty oils and other fats is so widely practiced in order to preserve them. Unsaturated fatty acids, especially those with two or more double bonds, are highly unstable and their breakdown to free acid – odoriferous aldehydes, organic peroxides, ketones, and other volatile substances – is responsible for much of the decomposition of foodstuffs. Likewise, the oxidation of the double bonded fatty acids to form ozonides and polymers renders the substance less digestible. Some of the compounds resulting from the breakdown of fatty acids may be not only distasteful but actually poisonous to man. The process of rancidity can be greatly hastened by heat and other methods of handling foods. In some fats, there are important antioxidants among which are the tocopherols or substances with vitamin E activity. The alpha-tocopherol, in particular, possesses this property. Although it is present in all meat to some degree, there are certain vegetable fats and oils that appear to be much richer in this type of material than others.
Hansen… fully discussed the importance of unsaturated fatty acids and their effects, especially when administered in the form of pork fat to the eczematous child. It will be found that pork tends to concentrate unsaturated fatty acids to a degree greater than many animals. Inasmuch as cutaneous lesions in experimental animals have been shown to be due to the lack of the unsaturated fatty acids, and not the saturated, pork appeared to be an excellent source of these materials. The author’s approach to the problem of the eczematoid and dermal conditions in general was stimulated by a slightly different point of view. Lamb fat offered several advantages, both theoretical and practical, over the use of pork. Lamb is a meat that can be consumed rare and for that matter is consumed raw by people in many parts of the world. Raw meats contain factors that are destroyed in the usual preparation of meats, especially if they are well done. The possibility of infection from pork precluded its use as rare meat. Secondly, the sheep is naturally a fat animal, bred for the purpose of producing meat, wool, and fat. It excretes in its wool a fatty substance containing esters, cholesterol, vitamins, and hormones, as well as steroids that go to make up lanolin. Inasmuch as the primary source of this highly curative wool fat must come from animal metabolism, it is reasonable to suspect that the fat depot of this animal might be expected to contain some of these substances in reserve supply.… It is, likewise, found that freshly cut meat has considerable advantage over meat cut one or more days in advance, inasmuch as oxidation takes place on the surface of the meat and actually changes the flavor for as much as an eighth of an inch with pieces that have been cut not over 24 hours. Freshness is important.
Evidence of fat deficiency in the American public has become of great concern to the physiologist, as has been so expressed in recent textbooks dealing with the subject. Beauty experts have written on the problem extensively, especially the problem of dry skin. In my own practice, we analyzed one hundred consecutive examinations representing fifty men and fifty women. Twenty-five of the fifty men had evidence of dry skin. Thirty-seven of the fifty women showed similar evidence. Simple dry skin is an index of fat dyscrasia. Although in the adult, more women appear to have dry skin than men, in our practice, the male child has greater evidence than the female.
Fat deficiency in the mammalian species is not corrected by fats composed of saturated fatty acids. It is only those unsaturated fatty acids of two or more double bonds that prevent the development of this condition, and the double bond fatty acids of four or more are more effective in a curative manner. The rare lamb chop has proven an excellent food source of unsaturated fatty acids and can bring about changes noticeable in the skin of patients who have been on a low fat consumption in as short a period of time as 48 hours. This change can be detected by a softening of the skin; and as the patient continues to consume the rare lamb chop, the velvety return to the normal skin can be gradually noted. Follicular keratoses that are so common on the legs and buttocks of many fat-starved individuals gradually disappear. When a lamb chop is prescribed, it is understood that all of the fat is to be eaten. Although many people feel that they cannot consume fats, there are few, indeed, who are truly unable to handle this form of fat. When digestive difficulties are present, they are usually due to insufficient gastric, pancreatic, or liver function. A substitution of suitable digestants can usually suffice to enable the patient to handle his meat unless natural prejudice or serious disease of the biliary tract or stomach precludes its use. The average patient, although his complaints may be multiple, who does not suffer from serious organic disturbance other than the dry skin, responds well. One can see the change in the hair as quickly as in the skin. It has been common to find boys with unruly hair who have been plastering it down with greases or other cosmetic preparations, within less than a week’s time show sufficient return of natural oil to their scalp so that the texture of the hair becomes soft and the subject can be properly groomed.
These results are not obtained if the patient removes the fat from his lamb chop [or] if he does not consume it rare. The average one-inch chop should be cooked no longer than two minutes on a side at 450° F. Nor are the results obtained well from the use of rare beef fat. The usual fats, pasteurized butter and oleomargarine, frequently reported as being consumed in relatively large amounts, do not possess the factors necessary to correct this condition in spite of the fact that the tables of composition of many oleos and butter show the presence of unsaturated acids.
Many people in their desire to follow the fashion of the day have lost especially important depot fat pads which are of special significance, namely, the sucking pads in the cheeks, the fat pads around the lips, and the fat pads in the palms and plantar fascia that serve to protect the metacarpal and metatarsal bones from mechanical injury. The loss of gluteal fat pads, particularly in older people, is a serious problem. The return of these important fat depots is much slower than the cutaneous manifestations mentioned above. Although depot fats may be returned to the subcutaneous tissue relatively quickly, the return of these protective fat pads is much slower and difficult of attainment.
Frequently, particularly women are unable to grasp objects firmly because of lack of these pads on the fingers or the palms of their hands. Frequently painful feet are associated with the loss of these pads and difficulty in walking may actually be experienced. Loss of protective pads over the tuberosities of the ischia renders sitting very uncomfortable for many Americans, not merely the aged. Once these pressure pads are lost, it frequently requires from one to three years in the younger individual to replace them. If, on the other hand, the individual has entered into the declining years beyond his fifties, once these protective pads have been resorbed, adequate fat intake over a long period may be insufficient to return these individuals to comfort. The elderly patient who has lost his fat pad may be made more uncomfortable by a fat-restricting diet than any fundamental condition which has made the clinician feel the necessity for such restriction.
The great fear of the production of hypercholesterolemia through the use of fats does not appear to be justified when the rare lamb chop is used for the major source of fat. The author has previously reported that a high-fat diet of animal origin did not alter the cholesterol level when used in conjunction with lecithin, a lipotropic agent, but actually diminished the cholesterol level. Inasmuch as a high lamb fat diet has not been attended with any evidence of damage, and cholesterols have not increased but have diminished in conjunction with a lipotropic agent, this source of animal fat appears to be of great value in the treatment of simple dry skin and other fat dyscrasias.
The rare lamb chop with all its fat provides an excellent source of unsaturated fatty acids that appear to be curative for the usual dry skin that is seen in such a high percentage of individuals today. It seems to be an excellent source for returning fat pads to the younger individual. It may not be successful in returning fat pads to the older person, although it may materially improve his general nutrition.
Ed. note: Excerpted from an article that appeared in the Spring 1957 issue of Journal of Applied Nutrition (Vol. 10, No. 2) and was reprinted in the Fall 2002 issue of Health and Healing Wisdom Journal, predecessor of the Price-Pottenger Journal of Health and Healing. This is one of the many articles by Dr. Pottenger that can be found in the Price-Pottenger research archives.
About the Author
Francis M. Pottenger, Jr., MD, (1901-1967) dedicated his professional life to understanding the role of nutrition in the prevention of chronic illness and physical degeneration. He was best known for his ten-year feeding study examining the effects of feeding cooked and heat-processed vs. raw foods to cats, the findings of which were chronicled in the book Pottenger’s Cats (available from Price-Pottenger). Dr. Pottenger served as president of the Los Angeles County Medical Association, American Therapeutic Society, and American Academy of Applied Nutrition. In 1940, he founded the Francis M. Pottenger, Jr., Hospital in Monrovia, California, for the treatment of respiratory diseases.
- Hansen AE. Study of iodine number of serum fatty acids in infantile eczema. Proc Soc Exper Biol and Med. 1933; 30(9):1198-1199.
- Pottenger FM Jr. The effect of heat-processed foods and metabolized vitamin D milk on the dentofacial structures of experimental animals. Am J Orthodontics and Oral Surg. 1946; 32(8):467-485.
- Pottenger FM Jr. A Common form of fat dyscrasia: dry skin. Southern Medical J. 1950; 43(2):165-168.
- Van Wagtendonk WJ, Wulzen R. Physiological and chemical aspects of the antistiffness factor essential for guinea pigs. In: Harris RS, Thimann KV. Vitamins and Hormones, Vol. 8. New York: Academic Press Inc., 1951; 69-125.
- Pottenger FM Jr, Krohn B. Reduction of hypercholesterolemia by high-fat diet plus soybean phospholipids. Am J of Digestive Diseases. 1952; 19(4):107-109.
Published in the Price-Pottenger Journal of Health and Healing
Winter 2021-22 | Volume 45, Number 4
Copyright © 2021 Price-Pottenger Nutrition Foundation, Inc.®
All Rights Reserved Worldwide