JOINT FAO/WHO FOOD STANDARDS PROGRAMME. CODEX COMMITTEE ON NUTRITION AND FOODS FOR SPECIAL DIETARY USES Twenty-sixth Session

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1 Agenda Item 10 CX/NFSDU 04/11 July 2004 JOINT FAO/WHO FOOD STANDARDS PROGRAMME CODEX COMMITTEE ON NUTRITION AND FOODS FOR SPECIAL DIETARY USES Twenty-sixth Session Brückenforum Bonn, Friedrich-Breuer-Strasse 17, Bonn, Germany, 1 5 November 2004 DISCUSSION PAPER ON DEFINITION FOR TRANS FATTY ACIDS Prepared by Malaysia and Denmark Background The 31 st Session of the Codex Committee on Food Labelling (CCFL), 28 April-2 May 2003, Ottawa, Canada discussed the declaration of trans fatty acids (TFAs) in the Draft Amendments to the Guidelines on Nutrition Labelling. Several delegations proposed to delete the declaration of TFAs because the scientific basis for the declaration of TFAs was insufficient, a distinction should be established between different types of TFAs and that their declaration was not meaningful for consumers. Other delegations and the Observers from the European Commission (EC) and Consumers International pointed out that the declaration of TFAs was relevant for consumers and that substantial scientific evidence demonstrated their adverse relationship with cardiovascular diseases (CVD). Some delegations proposed to include a definition of TFAs for the purposes of nutrient declaration and the Delegation of Canada proposed to include a footnote referring to non-conjugated fatty acids. As it was not possible to reach a final conclusion at this stage, the Committee agreed that the declaration of TFAs should be left to national legislation and amended the text accordingly. The Codex Committee on Food Labelling (CCFL) also requested that the Codex Committee on Nutrition and Foods for Special Dietary Uses (CCNFSDU) to provide a definition of TFAs for the purposes of the Guidelines and agreed to consider this question further when such advice became available. The 26 th Session of the Codex Alimentarius Commission (CAC), Rome, 30 June-7 July 2003 adopted the Draft Amendment at Step 8 as proposed by the CCFL. The CAC however, requested the CCFL to continue its work on TFAs in cooperation with the CCNFSDU and also asked the FAO and WHO to provide advice on the available scientific data to facilitate a final decision on this issue. The 25 th Session of the CCNFSDU, Bonn, Germany, 3-7 November 2003 noted that discussions on the definition of TFAs required more time and preparation, and therefore accepted the kind offer of the delegation from Malaysia in cooperation with Denmark and other interested parties working electronically, to prepare a discussion paper for consideration at the next Session of the CCNFSDU.

2 CX/NFSDU 04/11 2 PROPOSED DEFINITION OF TRANS FATTY ACIDS For the purpose of the Codex guidelines on Nutrition Labelling and other related Codex Standards and Guidelines, trans fatty acids are defined as all the geometrical isomers of monounsaturated and polyunsaturated fatty acids having non-conjugated [interrupted by at least one methylene group (-CH 2 - CH 2 -)] carbon-carbon double bonds in the trans configuration. This includes the trans monoenes (mainly stereoisomers of elaidic acid) and the trans isomers of polyunsaturated fatty acids (e.g. trans dienes, trans trienes etc.) with non-conjugated carbon-carbon double bonds, produced through hydrogenation of oils and fats (both vegetable and animal/marine origin) in the presence of a suitable chemical catalyst. The definition however excludes those conjugated trans fatty acids present naturally in animal fats and their products which include conjugated linoleic acid (CLA). Some background information on trans fatty acids and their health impact are summarised in the Appendix. RECOMMENDATION It is proposed that the 26 th session of CCNFSDU recommends the adoption of the definition for trans fatty acids for use in the Codex Guidelines on Nutrition Labelling and other related Codex Standards and Guidelines.

3 CX/NFSDU 04/11 3 Appendix BACKGROUND INFORMATION ON TRANS FATTY ACIDS Note: This appendix summarises information on the nature and occurrence of trans fatty acids as well as their potential impact on human health. This is not meant to be a comprehensive review of the subject but merely serves to provide some background information to assist in understanding of the proposed definition on trans fatty acids. Several recent reviews on the subject have been published, for example the detailed review by the Institute of Medicine (2002). NATURE AND OCCURRENCE OF TRANS FATTY ACIDS Generally, trans fatty acids (TFAs) refer to a heterogenous group of unsaturated fatty acids having a trans configuration at the site of at least one carbon-carbon double bond in its molecular structure. TFAs are naturally present in animal fats as a consequence of biohydrogenation of fatty acids by microorganisms in the rumen. Mainly C18 monoenoic trans fatty acids are formed with predominance of the delta 11 isomer trans vaccenic acid. TFAs are also produced as a result of hydrogenation of unsaturated oils and fats, which causes the isomerisation of some or all of the natural cis-configuration at carbon-carbon double bonds in the component fatty acids to the trans-configuration. The major TFA formed during commercial hydrogenation of oils and fats is the trans isomers formed by hydrogenation of C18:1 with unsaturation in the 9, 11 and 11 positions. Trans monoenes (trans fatty acids with one double bond), together with smaller amounts of trans dienes and trienes formed during commercial hydrogenation of oils and fats, are generally regarded as harmful to human health. Natural TFAs occur in a concentration of 4-6% of the fat from ruminants, whereas industrially produced trans fatty acid may occur in concentration of up to 60% of the fat. Recent studies suggest that not all species of TFA are bad. A group of naturally- occurring trans geometric and positional isomers of cis-linoleic acid possess carbon double bonds that are conjugated and have been given the collective term conjugated linoleic acid (CLA). CLA, consisting mainly of the cis-9,trans-11 and trans-10,cis-12 isomers, are formed in mammalian cells by the action of the enzyme 9 desaturase and therefore occur naturally in milk fat and dairy products (Adlof et al., 2000; Pariza at al., 2001; Santora et al., 2000). CLA are suggested to have beneficial effects on human health such as the inhibition of carcinogenesis and atherogenesis primarily based on cell culture studies and animal studies. (Ha et al., 1989; Kritchevsky et al., 2000; Parodi, 1999). However, further research work needs to be done to reinforce these findings. HEALTH IMPACT OF TRANS FATTY ACIDS (ELAIDIC ACID OTHER TFA SPECIES FORMED DURING COMMERCIAL HYDROGENATION OF OILS AND FATS) TFAs are bad for heart health Mensink and Katan (1990), provided early human clinical trial-evidence that TFAs can damage your heart. A total of 25 men and 34 women consumed each test diet for 3 weeks, with total fat at 36% energy. The transdiet increased not only total cholesterol and the bad low-density lipoprotein cholesterol (LDLC) but also markedly lowered the good high-density lipoprotein cholesterol (HDLC) concentrations, hence resulting in a less favourable TC/HDLC ratio. Their report was followed by numerous publications in scientific journals that the consumption of hydrogenated oils and fats containing TFAs increases the cardiovascular risk profile (Aro et al., 1997; Judd et al., 1994, 1998; Louheranta et. al., 1999; Muller et al.,1998; Sundram et al., 1997; Institute of Medicine of the National Academy of Sciences, USA, 2002). Recent data have demonstrated a dose-dependent relationship between TFA intake and the LDLC/HDLC ratio. When a meta-analysis of the results of several published human clinical trials were performed, TFAs were found to raise the

4 CX/NFSDU 04/11 4 LDLC/HDLC ratio (bad effect) about two times higher compared with the 12-16C saturated fatty acids (SFAs) (Ascherio et al., 1999). Plasma concentrations of the genetically-linked risk factor, Lipoprotein(a) [or Lp(a)], are associated with an increased risk of CVD and stroke. Interestingly, Lp(a) concentrations have been reported to be increased after the consumption of diets rich in hydrogenated fats/tfas (Almendingen et al., 1995; Aro et al., 1997; Lichtenstein et al., 1999; Mensink et al., 1992; Nestel et al., 1992; Sundram et al., 1997). Several large cohort studies have also found that the intake of TFAs increases the risk of coronary heart disease (Willett et al., 1993; Hu et al., 1997; Oomen et al., 2001). Viewing all the evidence, a Joint WHO/FAO Expert Consultation on Diet, Nutrition and the Prevention of Chronic Diseases (2003) recommended that to promote cardiovascular health, diets should provide a very low intake of TFAs- i.e. less than 1% of daily energy intake. Increase risk of type 2 diabetes In the Nurses Health Study, researchers from the Harvard School of Public Health examined the long-term relationship between different types of dietary fat and the risk of type 2 diabetes. More than 84,000 women who were healthy at baseline, were followed-up for 14 years during which time 2507 cases of type 2 diabetes were documented. The study showed that total fat, saturated fatty acids and monounsaturated fatty acids intakes were not associated with risk of type 2 diabetes in women. However, a high risk was associated with a high intake of TFA while a low risk was associated with a high intake of polyunsaturated fatty acids (PUFAs). The data suggest, that replacing 2% of energy from TFAs with PUFA reduce type 2 diabetes risk by almost 40% (Salmeron et al., 2001). Adverse health impact on infants A study by the University of British Columbia at Vancouver showed that Canadian women consume about 6.9 g (2.5% energy) of TFA/day, principally as bakery products, snacks, fast foods, and margarines containing hydrogenated fats. In lactating women, the dietary TFAs tend to displace the essential fatty acids (EFAs: linoleic acid and alpha-linolenic acid) in human milk, and eventually the TFAs end up in the plasma phospholipids and triglycerides of their breast-fed infants (Innis and King, 1999). The PUFA status of the developing foetus depends on that of its mother, as confirmed by the positive relation between maternal PUFA consumption and neonatal PUFA status. Consistent with the findings of the above Canadian study, researchers from the Maastricht University in the Netherlands showed that consumption of TFAs appeared to be associated with lower maternal and neonatal PUFA status. In addition, the presence of TFAs in cord tissue was associated with proportionally lower amounts of essential PUFAs, a reduced birth weight, and a smaller head circumference (Hornstra, 2000). In view of these findings, it seems prudent to reduce the maternal intake of TFAs as much as possible, while we await the negative effects of TFAs on foetal development to be reinforced.

5 CX/NFSDU 04/11 5 REFERENCES ALINORM 03/22A- Report of the Thirty-First Session of the Codex Committee on Food Labelling, Ottawa, Canada, 28 April-2 May ALINORM 03/41- Report of the Twenty-Sixth Session of the Codex Alimentarius Commission. Rome, 30 June-7 July ALINORM 04/27/26- Report of the Twenty-Fifth Session of the Codex Committee on Nutrition and Foods for Special Dietary Uses, Bonn, Germany, 28 April-2 May Aro, A; Jauhiainen, M; Partanen, R; Salminen, I; Mutanen, M(1997). Stearic acid, trans fatty acids and dairy fat: Effects on serum and lipoprotein lipids, apolipoproteins, apolipoprotein (a), and lipid transfer proteins in healthy subjects. Am. J Clin Nutr 65: Ascherio, A.; Katan, M B; Zock, P L; Stampfer, M J and Willet, W C (1999). Trans fatty acids and coronary heart disease. N. Eng. J. Med. 340: Ha, Y L; Grimm, N K; Pariza, N W (1989). Newly recognized anticarcinogenic fatty acid: Identification and quantification in natural and processed cheeses. J Agric. Food Chem. 37: Hornstra G (2000) Essential fatty acids in mothers and their neonates. Am J Clin Nutr, 71(5):1262S. Hu FB et al. (1997) Dietary fat intake and the risk of coronary heart disease in women. New Eng J Med, 337(21): Innis SM and King DJ (1999) Trans fatty acids in human milk are inversely associated with concentrations of essential all-cis n-6 and n-3 fatty acids and determine trans, but not n-6 and n-3, fatty acids in plasma lipids of breast-fed infants. Am J Clin Nutr, 70: Institute of Medicine (2002) Letter Report on dietary reference intakes for trans fatty acids. Drawn from the report on Dietary Reference Intakes for Energy, Carbohydrate, Fibre, Fat, Fatty Acids, Cholesterol, Protein and Amino Acids. Food and Nutrition Board, Institute of Medicine, USA. Judd, J T; Clevidence, B A; Muesing, R A; Wittes, J; Sunkin, M E; Podczasy, J J (1994). Dietary trans fatty acids: Effects on plasma lipids and lipoproteins of healthy men and women. Am. J Clin. Nutr. 59: Kritchevsky, D; Tepper, S A; Wright, S; Tso, P; Czarnecki, S K (2000). Influence of conjugated linoleic acid ( CLA) on establishment and progression of artherosclerosis in rabbits. J Am. Coll. Nutr. 19:472S-477S. Lichstenstein, A H; Ausman, L M; Jalbert, S M; Schaefer, E J (1999). Effects of different forms of dietary hydrogenated fats on serum lipoprotein cholesterol levels. N. Eng. J. Med. 340: Louheranta, A M; Turpeinen A K, Vidren, H M; Schwab, U S; Uusitupa, M I J (1999). A high trans fatty acid diet and insulin sensitivity in young healthy women. Metabolism 48: Mensink, R P and Katan, M B (1990). Effect of dietary trans fatty acids on high-density and low-density lipoprotein cholesterol levels in healthy subjects. N. Eng. J. Med.323: Mensink, R P; Zock P L and Katan, M B; Honstra, G (1992). Effect of dietary cis and trans fatty acids on serum lipoprotein(a) levels in humans. J. Lipid Res. 33: Muller, H; Jordal, O; Seljeflot, I, Kierulf, P; Kirkhus, B; Ledsaak, O; Pedersen JI( 1998). Effect on palsma lipids and lipoproteins of replacing partially hydrogenated fish oil with vegetable fat in margarine. Br. J. Nutr. 80:

6 CX/NFSDU 04/11 6 Nestel, P J; Noakes, M; Belling, B; Mc Arthur, R; Clifton, P; Janus. E; Abbey, M (1992). Plasma lipoprotein lipid and Lp(a) changes with substitution of elaidic acid for oleic acid in the diet. J. Lipid Res.33: Oomen CM et al. (2001) Association between trans fatty acid intake and 10-year risk of coronary heart disease in the Zutphen Elderly Study: a prospective population-based study. Lancet, 357: Pariza, M W; Park, Y; Cook, M E (2001). The biologically active isomers of conjugated linoleic acid. Prog. Lipid Res 40: Parodi PW (1999) Conjugated linoleic acid and other anticarcinogenic agents of bovine milk. J Dairy Sci, 82: Salmeron J, Hu FB, Manson JE et al. (2001) Dietary fat intake and risk of type 2 diabetes in women. Am J Clin Nutr, 73: Santora, J E; Palmquist, D L Roehrig, K L (2000). Trans-vaccenic acid is desaturated to conjugated linoleic acid in mice. J Nutr. 130: Sundram, K; Anisah, I; Hayes, K C; Jeyamalar, R and Pathmanathan, R (1997). Trans (elaidic) fatty acids adversely impact lipoprotein profiles relative to specific saturated fatty acids in humans. Br. J. Nutr., 68: Willet WC et al. (1993) Intake of trans fatty acids and risk of coronary heart disease among women. Lancet, 341: WHO/FAO (2003) Diet, Nutrition and the Prevention of Chronic Diseases. WHO Technical Report Series 916.