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HEALTH AND PALM OIL BASIC FACTS I ntroductionFacts on Palm Oil and Palm Olien Significant scientific findings and propositions arise from painstaking efforts in many laboratories. Once these observations withstand the scrutiny of time and re-evaluation by peer review they eventually become accepted as FACTS. Research has confirmed and established many scientific facts about nutritional effects of palm oil, twelve of which are present here. Each fact has been thoroughly examined and evaluated by scientists dedicated to discovering scientifically proven data about palm oil, regardless of popular perceptions or misconceptions. The scientific experiments of which these facts are based have been conducted in some of the world's most respected laboratories, using methods based on universally approved principles, to render them worthy of international acceptance. This compilation of documented facts on the nutritional effects of palm oil has been published in full or in part in international scientific journals and is endorsed by committees of several of the most recognized and respected nutrition scientists in this field.
Palm oil has been a safe and nutritious source of edible oil for healthy humans for thousands of years1. Palm oil and its liquid fraction, palm olein, are comsumed worldwide as cooking oils and as constituents of margarines and shortenings; these oils are also incorporated into fat blends used in the manufacture of a variety of food products as well as in home food preparation. Like other common edible fats and oils, palm oil is easily digested, absorbed and utilized in normal metabolic processes. It plays a useful role in meeting energy and essential fatty acid needs in many regions of the world <2>. Palm oil, like other vegetable oils, is cholesterol free <3>. Having a naturally moderate level of saturation, it does not require hydrogenation for use as a fat component in foods and, as such, does not contain trans fatty acids <3,4>. Fact 5 Red (unprocessed) and red or golden (specially refined) palm oils, the major cooking oils in many parts of the world, are rich sources of beta-carotene, an antioxidant, and precursor of Vitamin A and tocotrienols, all of which have antioxidant properties <5>. Palm oil and palm oil products are naturally occurring sources of the antioxidant vitamin E constituents, tocopherols and tocotrienols. These natural antioxidants act as scavengers of damaging oxygen free radicals and are hypothesized to play a protective role in cellular aging, atherosclerosis and cancer <6,7,8,9>. Palm olein contains a mixture of polyunsaturated, monounsaturated and saturated fatty acids. The relative concentrations are 44% oleic acid, 10% linoleic acid, 40% palmitic acid and 5% stearic acid. The concentration of palmitic and oleic acids are reversed in unfractionated palm oil i.e. 44% and 40% respectively. The fatty acid composition of palm oil is similar to that of the adipose tissue in most people on an ordinary diet. Palm oil triglycerides carry linoleic acid predominately in the 2-position, which favors absorption and availability for use in the body.
Palm oil from the fruit of the palm is physically and chemically different from either palm kernel oil which is derived from the seed, and from coconut oil, both of which are highly saturated. Human feeding studies and epidemiologic data have shown that palm oil or palm olein do not ordinarily raise blood cholesterol levels in direct comparison with olive or canola and peanut oils <10,11>. In several such studies blood cholesterol was reduced from entry level values and palmitic acid (16:0) was found equivalent to oleic acid (18:1) insofar as it affected cholesterol metabolism <11,12,13>. A balance between linoleic (18:2) and palmitic (16:0) acids may be required to maximize HDL levels <14>. Substitution of palmitic acid (16:0) from palm oil or palm olein for the lauric acid (12:0) and myristic acid (14:0) combination from palm kernel or coconut oils leads to a decrease in plasma and LDL cholesterol <15,16,17>. Of several fats tested, including a fat blend approximating American intake, a palm oil enriched diet fed to hamsters induced the highest level of protective HDL-cholesterol and the greatest production of liver LDL receptors, key to removal of harmful LDL-cholesterol from the blood <18>. Rats fed a palm oil-enriched diet have a reduced tendency for blood clotting <19>. Red palm olein is a major source of carotenoids which effectively inhibit some types of cancer. A diet containing palm oil, compared to diets based on other oils but which provide the same number of calories, exerted an inhibitory effect on the development and incidence of experimental-induced breast cancer in rats <20,21>. It has also been shown that the tocotrienols present in palm oil inhibiting the growth of cancer cells in vivo <22,23> as well as in vitro <24,25>.
1.Cottrell, R.C., (1991) Nutritional aspects of palm oil. Am.J.Clin.Nutr.53:989S-1009S. 3.Agriculture Handbook 8-4 (1979). Composition of Foods, United States Department of Agriculture, Science and Education Administration, Washington,D.C. 4.Life Sciences Research Office (1985). The Health Aspects of Trans-Fatty Acids, Federation of American Societies for Experimental Biology, Rockville, MD. 5.Krinsky, N.I. (1993). Actions of carotenoids in biological systems. Ann. Rev. Nutr. 13:561:588. 6.Walton, J.R. and Packer, L. (1980) Free radical damage and protection: relationship to cellular aging and cancer. In: Vitamin E, a Comprehensive Treatise, ed. L.J. Machlin, Marcel Dekker, Inc. New York, pp. 495-517. 7.Hirai, S., Okamoto, K., and Morimatsu, M. (1982). Lipid peroxide in the aging process. In: Lipid Peroxides in Biology and Medicine, ed. K. Yagi, Academic Press, New York, pp.305-315. 8.Cross, C.E., (1987). Oxygen radicals and human disease. Ann. Int. Med. 197:526-545. 9.Elson, C.E. and Qureshi, A.A. (1995). Coupling the cholesterol and tumor-suppressive actions of palm oil to the impact of its minor constituents on 3-hydroxy-3-methylglutaryl coenzyme A reductase activity. Prosta. Leuko. Ess. Fatty Acids. 52:205-208. 10.Wood, R., Kubena, K., Tseng, S., Martin, G. and Crook, R. (1993). Effect of palm oil, margarine, butter and sunflower oil on the serum lipids and lipoproteins of normocholestrolemic middle-aged men. J. Nutr. Biochem. 4:286-297. 11.Ng,T.K.W., Hayes, K.C., de Witt, G.F., Jegathesan, M., Satgunasingham, N., Ong, A.S.H. and Tan, D.T.S (1992). Palmitic and oleic acid exert similar efects on serum lipid profile in the normocholestrolemic humans. J. Am. Coll. Nutr. 11:383-390. 12.Hayes, K.C., Pronczuk, A., and Khosla, P. (1995). A rationale for plasma cholesterol modulation by dietary fatty acids: Modelling the human response in animals. J. Nutr. Biochem., 6:188-194. 13.Choudhury, N., Tan, L., and Truswell, A.S. (1995). Comparison of palm olein and olive oil: Effects on plasma lipids and Vitamin E in young adults. Am. J. Clin. Nutr. 61:1043-1051. 14.Sundram, K., Hayes, K.C. and Siru, O.H. (1995). Both dietary 18:2 and 16:0 may be required to improve the serum LDL/HDL cholesterol ration in normocholestrolemic men. J. Nutr. Biochem., 6:179-187. 15.Ng, T.K.W., Hassan, K., Lim, J.B. Lye, M.S. and Ishak, R. (1991) Non-hypercholesterolemic effects of a palm oil diet in Malaysian volunteers. Am. J. Clin. Nutr. 53:1015S-1020S. 16.Sundram, K., Hayes, K.C., and Siru, O.H. (1994). Dietary palmitic acid results in a lower serum cholesterol than a lauric-myristic acid combination in normolipemic humans. Am. J. Clin. Nutr. 59:841-846. 17.Hayes, K.C., Pronczuk, A., Lindsey, S. and Diersen-Schade, D. (1991). Dietary saturated fatty acids (12:0, 14:0, 16:0) differ in their impact on plasma cholesterol and lipoproteins in human primates. Am. J. Clin. Nutr. 53:491-498. 18.Lindsey, S., Benattar, J. Pronczuk, A. and Hayes, K.C. (1990). Dietary palmitic acid (16:0) enhances HDL cholesterol and LDL receptor RNA abundance in hamsters. Proc. Soc. Exp. Biol. Med. 195:261-269. 19.Hornstra, G., (1988). Dietary lipids and cadiovascular disease. Effects of palm oil. Oleagineux 43:75-81. 20.Sylvester, P.W., Russell, N., Ip, M.M. and Ip, C. (1986). Comparative effects of different animal and vegetable fats fed before and during carcinogen administration on mammary tumorigenesis, sexual maturation and endocrine function in rats. Cancer Res. 46:757-762. 21.Sundram, K., Khor. H.T., Ong, A.S.H. and Pathmarathan, R. (1989). Effect of dietary palm oils on mammary carcinogenesis in female rats induced by 7,12-dymethylbenz (a) anthracene.Cancer Res. 49:1447-1451. 22.Komiyama, K., Iizuka, K., Yamaoka, M., Watanabe, H., Tsuchiya, N and Umezawa, I. (1989). Studies on the biological activities of tocotrienols. Chem. Pharm. Bull. 37:1369-1371. 23.Goh, S.H., Hew, N.F., Norhanom, A.W. and Yadav, M. (1994). Inhibition of tumor promotion by various palm oil tocotrienols. Int. J. Cancer. 57:529-531. 24.Guthrie, N., Nesaretnam, K., Chambers, A.F. and Carroll, K.K. (1993). Inhibition of breast cancer cell growth by tocotrienols. FASEB J. 7:A70. 25.Guthrie, N., Chanbers, A.F., Gapor, A. and Carroll, K.K. (1995). In vitro inhibition of proliferation of receptor-positive MCF-7 human breast cancer cells by palm oil tocotrienols. FASEB J. 9:A988.
For this
webpage "Health & Palm Oil: Basic Facts"
compiled by:
SOURCE: INTERNATIONAL NUTRITION ADVISORY COUNCIL AND NUTRITIONAL ADVISORY COMMITEE
Palm oil from the fruit of the palm is physically and chemically different from either palm kernel oil which is derived from the seed, and from coconut oil, both of which are highly saturated.
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