Letter to the Editor: Is Stearic Acid a Whole- some Substitute for Trans Fatty Acids? Rafael Monge-Rojas 1 , PhD, and Walter Willet 2 , MD, Dr PH 1 Costa Rican Inst. for Research and Education on Nutrition and Health (INCIENSA), Ministry of Health, Tres R´ ıos, Costa Rica 2 Dept. of Nutrition, Harvard School of Public Health, Boston, Mass., USA. To the Editor: We read with interest Crupkin and Zambelli’s (2008) review suggesting that stearic acid is a wholesome substitute for trans fatty acids and other saturated fatty acids in food manufacturing. Crupkin and Zambelli appropriately state that industrially pro- duced trans fatty acids should be excluded from the diet given the strong evidence from controlled feeding studies and epidemi- ologic findings. However, we disagree with their proposal to use stearic acid as a major substitute for trans fatty acids because there are limited data on the health effects of long-term intake of high amounts of stearic acid. Although stearic acid has a neu- tral effect on plasma total cholesterol, some evidence, although not conclusive, suggests effects on thrombotic, inflammatory, and hemodynamic pathways (Kris-Etherton and others 2001; Baer and others 2004). Further, in a study by Sundram and others (2007), high intake of stearic acid as an interesterified fat caused serious dysregulation of glucose metabolism. In that study, the intake was high and the design did not allow a separation of the effects of stearic acid from those of interesterification, yet the findings raise issues that need to be resolved. Epidemologic findings are limited, but available data raise con- cern. In the large prospective cohort of 80,082 women in the Nurses’ Health Study (Hu and others 1997), out of all the saturated fatty acids, stearic acid was most strongly associated with CHD risk. Also, in the Costa Rican Heart Disease Study (Kabagambe and others 2003), intake of all saturated fatty acids, including stearic acid, was independently associated with an increased risk of nonfatal acute myocardial infarction. We note that the Report of the trans Fat Conference Planning Group (Eckel and others 2007) pointed out that interesterification has not been fully examined for its effects on health. We consider the use of stearic acid in substantial amounts, either in natural or randomized triglycerides, to replace trans fatty acids in food man- ufacturing to be premature. More research is needed to achieve a comprehensive understanding of the long-term effects on human health of high intakes of stearic acid. References Baer D, Judd JT, Clevidence BA, Tracy RP. 2004. Dietary fatty acids affect plasma markers of inflammation in healthy men fed controlled diets: A randomized crossover study. Amer J Clin Nutr 79:969–73. Crupkin M, Zambelli A. 2008. Detrimental impact of trans fat on human health: Stearic acid–rich fats as possible substitutes. Comp Rev Food Sci Food Saf 7:273–9. Eckel R, Borra S, Lichtenstein A, Yin–Piazza S. 2007. Understanding the complexity of trans fatty acid reduction in the American diet. American Heart Association trans Fat Conference 2006: Report of the trans fat conference planning group. Circulation 115:2231–46. Hu FB, Stampfer MJ, Manson JE, Rimm E, and others. 1997. Dietary fat and risk of coronary heart disease in women. New Engl J Med 337:1491–9. Kabagambe EK, Baylin H, Siles X, Campos H. 2003. Individual saturated fatty acids and nonfatal acute myocardial infarction in costa rica. Eur J Clin Nutr 57:1447–57. Kris–Etherton P, Daniels S, Eckel R, and others. 2001. American Heart association scientific statement: Summary of the scientific conference on dietary fatty acids and cardiovascular health. Circulation 103:1034–9. Sundram K, Karapaiah T, Hayes KC. 2007. Stearic acid–rich interesterified fat and trans–rich fat raise the LDL/HDL ratio and plasma glucose relative to palm olein in humans. Nutr Metab (Lond). 2007 Jan 15; 4:3. Response from the Authors Marcos Crupkin 1 and Andres Zambelli 2 1 Area Biomolecular y Area de Alimentos (E-mail: mcrupkin@mdp.edu.ar ) and 2 Posgrado en Producci ´ on Veg- etal, Facultad de Ciencias Agrarias, Univ. Nacional de Mar del Plata, CC 276, Ruta 226, Km 73.5, Balcarce (7620), Pcia. de Buenos Aires, Argentina. We really appreciated Monge-Rojas and Willet’s comments on our paper recently published in Comprehensive Reviews in Food Science and Food Safety (Crupkin and Zambelli 2008). In spite of the fact that these authors recognize that stearic acid has a neutral effect on plasma cholesterol, they disagree on the use of stearic acid-rich fats as major substitute for trans fats. However, in our review we analyzed an important number of scientific papers referring to the stearic acid impact on human health, just suggesting fats rich in this fatty acid might be a possible substitute of trans fatty acid. In their letter, Monge-Rojas and Willet cited a paper from Kabagambe and others (2003) in which it was found that stearic C  2008 Institute of Food Technologists R  Vol. 7, 2008—COMPREHENSIVE REVIEWS IN FOOD SCIENCE AND FOOD SAFETY 297