The development of essential fatty acid deficiency in healthy men fed fat-free diets intravenously and orally. J D Wene, … , W E Connor, L DenBesten J Clin Invest. 1975;56(1):127-134. https://doi.org/10.1172/JCI108061. Research Article The hypothesis that clinical and biochemical essential fatty acid deficiency (EFA) might occur from the feeding of eucaloric, fat-free diets was tested in two experiments in healthy men. In Study I, eight men were given fat-free, eucaloric diets containing 80% of calories as glucose and 20% as amino acid hydrolysates by a constant drip over a 24-h period. The diets were fed in succession for periods of 2 wk each, either through a superior vena cava catheter or via a nasogastric tube. EFA deficiency was detected by decreases in linoleic acid and by the appearance of 5, 8, 11- eicosatrienoic acid in lipid fractions of plasma. Linoleic acid decreased significantly during 2 wk of the fat-free diet given intravenously from 48.8 to 9.8% (percent of total fatty acids) in cholesterol esters, from 21.2 to 3.2% in phospholipids, from 9.6 to 2.0% in free fatty acids, and from 14.1 to 2.6% in triglycerides. Eicosatrienoic acid, normally undetectable, appeared 0.6% in cholesterol esters, 2.5% in phospholipids, 0.2% in free fatty acids, and 2.3% in triglycerides. EFA deficiency occurred similarly during the nasogastric feeding. In Study II a subject received the same diet continuously by the nasogastric route for 10 days followed by a 24-h fast. He was then given the fat-free diet intermittently in three meals per day for 3 days. Finally, he […] Find the latest version: https://jci.me/108061/pdf The Development of Essential Fatty Acid Deficiency in Healthy Men Fed Fat-Free Diets Intravenously and Orally JAMIE D. WENE, WILLIAM E. CONNOR, and LAWRENCE DENBESTEN From the Clinical Research Center and the Departments of Internal Medicine and Surgery, University of Iowa, College of Medicine, Iowa City, Iowa 52242 A B S T R A C T The hypothesis that clinical and bio- acid outflow from adipose tissue was presumably sup- chemical essential fatty acid deficiency (EFA) might pressed during the 10 days of continuous feeding. With occur from the feeding of eucaloric, fat-free diets was increased free fatty acid outflow during fasting and tested in two experiments in healthy men. In Study I, intermittent feeding, linoleic acid rose and eicosatrie- eight men were given fat-free, eucaloric diets containing noic acid decreased. After 13 days of repletion with 80% of calories as glucose and 20% as amino acid hy- dietary linoleic acid, the EFA deficiency had disappeared. drolysates by a constant drip over a 24-h period. The These results indicated that EFA deficiency readily diets were fed in succession for periods of 2 wk each, develops when fat-free diets containing glucose are either through a superior vena cava catheter or via a given intravenously or orally as constant 24-h infusions. nasogastric tube. EFA deficiency was detected by de- These diets are similar to the hyperalimentation formu- creases in linoleic acid and by the appearance of 5, 8. las now being used clinically. 11-eicosatrienoic acid in lipid fractions of plasma. Linoleic acid decreased significantly during 2 wk of the fat-free diet given intravenously from 48.8 to 9.8% INTRODUCTION (percent of total fatty acids) in cholesterol esters, from Essential fatty acid (EFA)' deficiency was first pro- 21.2 to 3.2% in phospholipids, from 9.6 to 2.0% in free duced experimentally in young, growing rats by Burr fatty acids, and from 14.1 to 2.6% in triglycerides. and Burr in 1929 (1). This syndrome has also been Eicosatrienoic acid, normally undetectable, appeared described in many other species including man (2). 0.6% in cholesterol esters, 2.5% in phospholipids, 0.2% The term "essential fatty acid" refers to linoleic acid in free fatty acids, and 2.3% in triglycerides. EFA de- (cis, cis-9,12-octadecadienoic acid). Linolenic acid (cis, ficiency occurred similarly during the nasogastric feed- cis, cis-9,12,15-octadeocatinenoic acid) will stimulate ing. growth but will not relieve the dermal symptoms asso- In Study II a subject received the same diet continu- ciated with EFA deficiency, while linoleic acid will ef- ously by the nasogastric route for 10 days followed by fectively correct both (3). Arachidonic acid (cis, cis, a 24-h fast. He was then given the fat-free diet inter- cis, cis-5,8,11,14-eicosatetraenoic acid) is approximately mittently in three meals per day for 3 days. Finally. he three times as effective as linoleic acid in promoting was repleted with a diet containing 2.6% linoleic acid. growth (2), but is not an essential nutrient since lino- By the 3rd day of the continuous nasogastric feeding, leic acid can be converted to arachidonic acid in the linoleic acid had fallen significantly and eicosatrienoic body (4). Linoleic acid then is the EFA, i.e., that fatty acid had appeared in plasma lipid fractions as in Study acid which must be obtained from the diet by most I. These findings were accentuated by day 10. Adipose species to prevent the symptoms of EFA deficiency. tissue fatty acid composition did not change. Free fatty The symptomatology of EFA deficiency falls into three categories: (a) gross abnormalities (e.g., cessa- Presented in part at the 1973 Annual Meeting of the tion of growth, dermatitis, loss of hair, and increased Central Society for Clinical Research. Received for publication 10 October 1974 and in revised 'Abbreviation used in this paper: EFA, essential fatty form 19 March 1975. acid. The Journal of Clinical Investigation Volume 56 July 1975.127-134 127 METHODS TABLE I Composition of the Hyperalimentation Diet Study I. Eight healthy male volunteers' from the Iowa State Penitentiary were admitted to the Clinical Research Casein hydrolysate 20% Center. A hyperalimentation diet was fed both intravenously Dextrose 80% and nasogastrically (Table I). This diet, "Central Venous Caloric density 1 kcal/ml Nutrient Solution," was 80% glucose, 20% casein amino Electrolytes Sodium 30 meq/liter acid hydrolysates (Amigenl, Baxter Laboratories, Morton Potassium 15 meq/liter Grove, Ill.) and was completely fat free. Appropriate elec- Calcium 12.5 meq/liter trolytes and vitamins were added to meet the daily nutri- Chloride 19.6 meq/liter tional requirements. Sterile solutions were prepared daily Magnesium 4.2 meq/liter at a caloric equivalent of 1 kcal/ml. To minimize the effect Phosphorus 24.6 meq/liter of weight change on serum lipids, a careful dietary history Vitamins Thiamine hydrochloride 25 mg was taken on admission to the Clinical Research Center, Riboflavin 10 mg and caloric needs were estimated both from this informa- Sodium pantothenate 20 mg tion and from the height and weight. The men were am- Nicatinamide 100 mg bulatory throughout the study and engaged in the usual Pyridoxine hydrochloride 20 mg ward recreational activities. Ascorbic acid 500 mg During the base-line 7-day period of the study, all sub- jects were fed a eucaloric general diet. The linoleic acid content of this diet was 2-3% of total calories. During the susceptibility to bacterial infections), (b) histological next two 14-day sequential periods each subj ect was fed abnormalities (e.g., microscopic changes in the kidneys, the eucaloric, fat-free hyperalimentation diet either by naso- gastric tube or intravenous catheter. The solutions were skin, ovaries, and testes), and (c) physiological and infused at a constant rate over 24 h. Four subjects in Group biochemical abnormalities (2, 5). The last category in- A received this nutrient solution for 14 days intravenously cludes biochemical changes in the fatty acid patterns of and then nasogastrically for another 14 days. The four sub- blood and organs such as liver and heart (6). These jects in Group B received this solution in reverse order. Each subject, therefore, was given the fat-free diet for a changes involve increased levels of 5, 8, 11-eicosatrie- total of 28 days. noic acid and decreased levels of linoleic acid and ara- The formula was infused through a 17-gauge plastic chidonic acid. The changes in blood levels may be the catheter which had been threaded through the subclavian earliest signs of EFA deficiency (2). vein into the superior vena cava under fluoroscopic control. All infusing solutions were passed through a 44 Asm filter Experimental studies have shown that the very young placed immediately proximal to the subclavian catheter. animals are much more susceptible to EFA deficiency Every 3rd day all dressings were removed and skin around than adults (7-9). Growing animals require linoleic the catheter was defatted with acetone. All catheter tips acid and their body stores are low, thereby making de- were cultured at the termination of the study and found to bb sterile. pletion easily producible. Because the dietary require- Study II. Subject E. R., a healthy male volunteer 21 ment is low and the storage of linoleic acid in adipose yr of age, was admitted to the Clinical Research Center tissue is great, it has been extremely difficult to produce for a more detailed study of the changes in serum fatty clinical EFA deficiency in adults. Most of the human acids which occurred in Study I subjects. A eucaloric studies reported to date have been in infants and chil- formula diet containing 2.6% of calories as linoleic acid was first fed for 2 mo. This was followed by four dietary dren (10-14). Only two cases of linoleic acid defic- periods: In Period A, a completely fat-free diet was iency have been reported in adult humans.