Trans Fatty Acid Isomers Research Articles

Isolation of α-linolenic acid biohydrogenation products by combined silver ion solid phase extraction and semi-preparative high performance liquid chromatography.

Polyunsaturated fatty acids typically found in cattle feed include linoleic (LA) and α-linolenic acid (ALA). In the rumen, microbes metabolize these resulting in the formation of biohydrogenation products (BHP), which can be incorporated into meat and milk. Bioactivities of LA-BHP, including conjugated linoleic acid (cis (c) 9,trans (t) 11-18:2 and t10,c12-18:2) and trans fatty acid isomers (t9-, t10- and t11-18:1) have been investigated, but effects of several BHP unique to ALA have not been extensively studied, and most ALA-BHP are not commercially available. The objective of the present research was to develop methods to purify and collect ALA-BHP using silver ion (Ag(+)) chromatography in sufficient quantities to allow for convenient bioactivity testing in cell culture. Fatty acid methyl esters (FAME) were prepared from perirenal adipose tissue from a cow enriched with ALA-BHP by feeding flaxseed. These were applied to Ag(+)-solid phase extraction, and eluted with hexane with increasing quantities of acetone (1, 2, 10, 20%) or acetonitrile (2%) to pre-fractionate FAME based on degree of unsaturation and double bond configuration. Fractions were collected, concentrated and applied to semi-preparative Ag(+)-high performance liquid chromatography (HPLC) for the isolation and collection of purified isomers, which was accomplished using isocratic elutions with hexane containing differing amounts of acetonitrile (from 0.015 to 0.075%). Purified trans-18:1 isomers collected ranged in purity from 88 to 99%. Purity of the ALA-BHP dienes collected, including c9,t13-18:2, t11,c15-18:2 and t10,c15-18:2, exceeded 90%, while purification of other dienes may require the use of other complementary procedures (e.g. reverse phase HPLC).

Theoretical and Practical Aspects of the Development of a Balanced Lipid Complex of Fat Compositions

In the paper, the effect of the lipid complex in fats and oils on human organism and their role in physiology of nutrition are reviewed. Aspects of impairment of the nutritional status upon fat consumption, in particular, the excess consumption of saturated fats, trans-isomers of fatty acids, and cholesterol and the deficiency of polyunsaturated fatty acids and phospholipids, are discussed. Data on oil and fat in modern structure of nutrition are described. Aspects of the development of balanced fat compositions, accounting for normal physiological needs of modern people for lipids and their structural components, are reviewed. Data on the construction of fatty bases from milk fat, natural, and modified vegetable oils and fats providing for predetermined consumer properties of functional fatty milk products are presented.

Commercializing University Research: Pathways, Pitfalls, and Personal Observations

With ever increasing frequency, universities are seeking to commercialize in-house intellectual property, as they search for new revenue streams that will help relieve budgetary pressures which traditionally have fallen on growing the endowment, increasing undergraduate tuition, and accumulating more research overhead money. Universities are providing attractive royalty sharing options to faculty and staff as an incentive to generate patentable IP. Technology transfer offices at U.S. universities have in-house patent attorneys or have retained an outside law firm which usually acts in a timely manner so as to not delay the public dissemination of a professor’s research results. In this regard, one can generally say that universities do a good job at protecting their intellectual property. Often, however, universities do poorly in marketing their protected ideas and they do not have the staff to fully/adequately evaluate the commercial potential of new inventions. Research universities are slow or incapable of performing the necessary due-diligence on every invention disclosure that comes to their technology transfer office. With limited budgets, tech transfer offices must pick and choose which inventions to protect, from a broad range of topics/disciplines, e.g., software programs from a computer science department, medical devices and new drugs from medical schools and hospitals, and new materials and processes from chemistry and chemical engineering departments. Such a wide spectrum of ideas is rarely seen in a single company. So it is often up to individual professors to justify and defend the importance and market value of their work.In this presentation, two examples will be given of university research projects that generated commercial interest, based on the author’s personal experience. The projects will be described in terms of a chronological timeline, where initial laboratory data led to all or most of the following: (1) some interest by one or more companies, (2) the filing of a patent by the university, (3) the early pursuit of third party non-industry collaborators to strengthen the credibility and acceptance of university research results by companies, (4) the marketing of the invention to companies by the university and professor, (5) the collection of new research results to expand the university’s IP position, and (6) the development/pursuit of a cooperative/licensing agreement with a company to commercialize the university invention. Issues that will be addressed in this presentation include: (a) patenting and publishing university research results; the two are not mutually exclusive, (b) pursuing process vs. product patents, (c) the new patent rule of first to file and its impact on research workplans at universities, (d) industry’s reluctance to accept at face value university-generated data, (e) working with companies to further develop university-owned IP, (f) industry’s focus on scale-up and cost issues vs. university interest in basic research, and (g) faculty interactions with patent attorneys and the university’s technology transfer office.Two commercialization projects will be described: (1) the synthesis of partially hydrogenated soybean oil with a low trans fatty acid content via an electrocatalytic hydrogenation process [1,2] and (2) nanofiber particle/polymer electrode mats for fuel cells and other electrochemical devices [3].The first project involves a process patent, where the partial hydrogenation of unsaturated fatty acids in an edible oil (e.g., soybean oil) is carried out at moderate temperature in a solid polymer electrolyte fuel cell reactor with neat oil at a reaction temperature much lower than that used in a chemical catalytic reaction scheme. Industrial interest in the electrochemical technology revolved around the low trans isomer content of the hydro-oil product; diets high in trans fatty acid isomers increase the risk of coronary heart disease. The second project involves university IP where the patent has both product and process claims. The work deals with catalyst/binder nanofiber mat electrodes for hydrogen/air proton exchange membranes fuel cells with possible spin-off applications in other electrochemical devices that require high surface area electrodes. Industrial interest stems from the low platinum loading, high power density, and excellent durability of nanofiber cathodes in a hydrogen/air fuel cell. References W. An, J. K. Hong, P. N. Pintauro, K. Warner, and W. Neff, J. Amer. Oil Chem. Soc., 75, 917-925 (1998).P.N. Pintauro, M. P. Gil, K. Warner, G. List, and W. Neff, Ind. & Engr. Chem. Res., 44, 6188-6195 (2005).M. Brodt, R. Wycisk, and P. N. Pintauro, J. Electrochem. Soc., 160, F744-F749 (2013).

Sodium arsenate induce changes in fatty acids profiles and oxidative damage in kidney of rats

Six groups of rats (n = 10 per group) were exposed to 1 and 10 mg/l of sodium arsenate for 45 and 90 days. Kidneys from treated groups exposed to arsenic showed higher levels of trans isomers of oleic and linoleic acids as trans C181n-9, trans C18:1n-11, and trans C18:2n-6 isomers. However, a significant decrease in eicosenoic (C20:1n-9) and arachidonic (C20:4n-6) acids were observed in treated rats. Moreover, the "Δ5 desaturase index" and the saturated/polyunsaturated fatty acids ratio were increased. There was a significant increase in the level of malondialdehyde at 10 mg/l of treatment and in the amount of conjugated dienes after 90 days (p < 0.05). Significant kidney damage was observed at 10 mg/l by increase of plasma marker enzymes. Histological studies on the ultrastructure changes of kidney supported the toxic effect of arsenate exposure. Arsenate intoxication activates significantly the superoxide dismutase at 10 mg/l for 90 days, whereas the catalase activity was markedly inhibited in all treated groups (p < 0.05). In addition, glutathione peroxidase activity was significantly increased at 45 days and dramatically declined after 90 days at 10 mg/l (p < 0.05). A significant increase in the level of glutathione was marked for the groups treated for 45 and 90 days at 1 mg/l followed by a significant decrease for rats exposed to 10 mg/l for 90 days. An increase in the level of protein carbonyl was observed in all treated groups (p < 0.05). In conclusion, the present study provides evidence for a direct effect of arsenate on fatty acid (FA) metabolism which concerns the synthesis pathway of n-6 polyunsaturated fatty acids and leads to an increase in the trans FAs isomers. Therefore, FA-induced arsenate kidney damage could contribute to trigger kidney cancer.

Intake of trans fatty acid isomers found in ruminant fat versus industrial sources differentially impact concentrations of fatty acids in erythrocytes (1025.17)

Evidence suggests concentration of trans fatty acids (TFA) in erythrocyte (RBC) membranes is strongly predictive of coronary heart disease (CHD) risk. Some data suggest a direct association with industrially‐produced TFA (iTFA) and CHD risk, and an inverse or no association with naturally‐occurring TFA in ruminant fat (rTFA). Differential incorporation of TFA isomers in RBC membranes from iTFA and rTFA may account for differences in CHD risk reported between the two sources; however, controlled dietary interventions comparing iTFA and rTFA have not measured RBC TFA isomers. In a double‐blind randomized‐controlled crossover feeding trial healthy adults (N=106; 47M, 59F) were fed 4 diets for 24 days each: 0.1% en mixed isomers TFA (control), 3.0% en highly‐purified vaccenic acid (VA), 3.0% en mixed isomers iTFA, and 1.0% en c9,t11‐CLA. Total fat (34% en) and other macronutrients were matched across diets. RBC VA was highest following the VA diet (P &lt; 0.05), while elaidic acid was highest following the iTFA diet (P &lt; 0.05). RBC c9,t11‐CLA was highest after the CLA diet (P &lt; 0.05), followed by the VA diet (P &lt; 0.05), indicating some conversion of VA to c9,t11‐CLA resulting from the dietary VA. In conclusion, highly‐purified dietary VA and c9,t11‐CLA differentially impact RBC fatty acid profiles compared to iTFA. Differences in RBC fatty acids impact membrane fluidity which may explain differences of rTFA and iTFA on CHD risk.Grant Funding Source: Supported by: USDA, Nestle, National Dairy Council, Dairy Australia

What are the trans fatty acids issues in foods after discontinuation of industrially produced trans fats? Ruminant products, vegetable oils, and synthetic supplements

Adverse health effect of trans fatty acids (TFAs) are well recognized, which has precipitated efforts to reduce their content in food products. With the decline of dietary TFAs derived from partial oil hydrogenation, interest is focused on the remaining sources of dietary TFAs derived from ruminants (rTFA), deodorized vegetable oils, trans isomerization during frying, and synthetic conjugated FA (CFA) supplements. Partial hydrogenation and heat‐treated oils result in a random distribution of TFA isomers, whereas rTFAs contain specific isomers resulting from enzymatic processes. Reviews of human observational and metabolic intervention studies have suggested that consumption of rTFAs at current levels should not raise health concerns. However, these studies were not based on rTFA levels currently sold in retail markets. Current feeding practices of ruminants result in higher total TFAs with trans‐18:1 isomers other than vaccenic acid, and many CFAs other than rumenic acid. The definition of TFA adopted by several countries does not distinguish among isolated TFAs of concern and ignores CFAs that should be included in total TFA due to their negative health effects. Accurate TFA definition establishment and nutritional assessment of individual TFA isomers is needed for labeling purposes. Also required are adoptions of analytical methods to resolve all TFA isomers. This information can then be used to construct a database and as a basis for meaningful recommendations.Practical applications: Areas that require further investigations have been identified: 1) Establish a uniform TFA nomenclature based on chemical structure. 2) Standardize, assess and normalize appropriate methodologies for the analysis of TFAs. 3) Synthesize pure reference standards for TFA identification. 4) Report total TFA levels with undesirable biological activities rather than total TFA content. 5) Assess the nutritional characteristics of individual TFAs independent of their origin. 6) Develop strategies to increase the content of desirable TFA isomers in ruminants. 7) Identify potential bioactive trans metabolites produced from PUFAs in ruminants. 8) Develop labeling regulations based on specific chemical structures and physiological effects regardless of their origin. 9) Construct an accurate database complemented with specific surveys of ruminant product fatty acid (FA) composition that can be accessed by regulatory agencies to make appropriate TFA recommendations.

Highlight Article summary: What are the trans fatty acids issues in foods after discontinuation of industrially produced trans fats? Ruminant products, vegetable oils, and synthetic supplements

SUMMARYAdverse health effect of trans fatty acids (TFAs) are well recognized, which has precipitated efforts to reduce their content in food products. With the decline of dietary TFAs derived from partial oil hydrogenation, interest is focused on the remaining sources of dietary TFAs derived from ruminants (rTFA), deodorized vegetable oils, trans isomerization during frying, and synthetic conjugated FA (CFA) supplements. Partial hydrogenation and heat‐treated oils result in a random distribution of TFA isomers, whereas rTFAs contain specific isomers resulting from enzymatic processes. Reviews of human observational and metabolic intervention studies have suggested that consumption of rTFAs at current levels should not raise health concerns. However, these studies were not based on rTFA levels currently sold in retail markets. Current feeding practices of ruminants result in higher total TFAs with trans‐18:1 isomers other than vaccenic acid, and many CFAs other than rumenic acid. The definition of TFA adopted by several countries does not distinguish among isolated TFAs of concern and ignores CFAs that should be included in total TFA due to their negative health effects. Accurate TFA definition establishment and nutritional assessment of individual TFA isomers is needed for labeling purposes. Also required are adoptions of analytical methods to resolve all TFA isomers. This information can then be used to construct a database and as a basis for meaningful recommendations.Practical applications: Areas that require further investigations have been identified: 1) Establish a uniform TFA nomenclature based on chemical structure. 2) Standardize, assess and normalize appropriate methodologies for the analysis of TFAs. 3) Synthesize pure reference standards for TFA identification. 4) Report individual TFA levels with different biological activities rather than total TFA content. 5) Assess the nutritional characteristics of individual TFAs independent of their origin. 6) Develop strategies to increase the content of desirable TFA isomers in ruminants. 7) Identify potential bioactive trans metabolites produced from PUFAs in ruminants. 8) Develop labeling regulations based on specific chemical structures and physiological effects regardless of their origin. 9) Construct an accurate database complemented with specific surveys of ruminant product FA composition that can be accessed by regulatory agencies to make appropriate TFA recommendations.

Trans Isomeric fatty acids are inversely related to the availability of long-chain PUFAs in the perinatal period

We summarize data on the potential interaction of trans isomeric fatty acids [trans fatty acids (TFAs)] with the availability of long-chain polyunsaturated fatty acids (LC-PUFAs) in the perinatal period. Today, TFA intakes in pregnant and lactating women can be estimated to be ∼1% of energy in the majority of the population. The significant inverse associations seen between TFAs and LC-PUFAs in pregnant women in 3 different European populations investigated in a recent study raise doubts about the nutritional adequacy of high TFA intakes during pregnancy. In a recent study on the TFA content of human milk in a sizable group of mothers at the sixth week of lactation, both arachidonic and docosahexaenoic acids correlated significantly inversely to 18-carbon TFAs but not to 16-carbon TFAs, and at the sixth month of lactation arachidonic acid correlated significantly inversely to 18-carbon TFAs but not to 16-carbon TFAs. Similarly, significant inverse correlations were seen between 18-carbon TFAs and arachidonic and docosahexaenoic acids in both artery and vein wall lipids in a sizable group of healthy term infants. The TFA data obtained in umbilical blood vessel wall lipids were related to the neurologic condition of healthy children at 18 mo of age: children with minimal neurologic dysfunction at age 18 mo had significantly higher cord blood vein wall trans octadecadienoic acid values than did neurologically normal children. Total TFA values as well as total 18-carbon TFA values in umbilical vein wall lipids were significantly inversely associated with neurologic optimality score. Contradictory data renders it impossible to draw firm conclusions on the role of TFAs in modifying fetal growth; however, TFA exposure may be a confounding parameter in studies that investigate the relation between fetal fatty acid supply and intrauterine growth.

The trans fatty acid content in human milk and its association with maternal diet among lactating mothers in Malaysia.

Excessive intake of trans fatty acids (TFA) could reduce the fat density of human milk and impair the desaturation of essential fatty acids. Because the mammary glands are unable to synthesize TFA, it is likely that the TFA in human milk come from dietary intake. Thus, the aim of this study was to investigate the sources of TFA intake for lactating mothers in one of the urban areas in Selangor. In this cross-sectional study, anthropometric measurements, FFQ including 7 food groups and dietary consumption data were collected from 101 lactating mothers. Five major TFA isomers (palmitoelaidic acid (16:1t9), petroselaidic acid (18:1t6), elaidic acid (18:1t9), vaccenic acid (18:1t11) and linoelaidic acid (18:2t9,12) in human milk were measured by gas chromatography (GC). The relationship between food consumption and TFA levels was assessed using the non-parametric Spearman's rho test. The TFA content in human milk was 2.94±0.96 (SEM) % fatty acid; this is considered low, as it is lower than 4%. The most abundant TFA isomer was linoelaidic acid (1.44±0.60% fatty acid). A sub-experiment (analyzing 3 days of composite food consumption) was conducted with 18 lactating mothers, and the results showed that linoelaidic acid was the most common TFA consumed (0.07±0.01 g/100 g food). Only 10 food items had an effect on the total TFA level and the isomers found in human milk. No association was found between TFA consumption and the TFA level in human milk.

An accurate and reliable method for identification and quantification of fatty acids and trans fatty acids in food fats samples using gas chromatography

A method for the separation, identification and further quantification of fatty acids (FAs) and trans fatty acids (TFAs) by gas chromatography (GC) using the combination of lipid extraction and derivatization with the base-catalysed method followed by trimethylsilyl-diazomethane (TMS-DM) was developed. The proposed method was found to allow sensitive and accurate determination of a wide range of different types of FAs, including TFA isomers. The method was validated on real samples of dietary fat from hydrogenated edible oils (margarine) and nine standard FAs as representatives of margarines. For this purpose, response linearity, limit of detection (LOD), limit of quantification (LOQ), precision and recovery (R%) were all determined. Based on the results obtained, R-values from all the samples were revealed to be close to 100%, repeatability RSD ranged between 0.89% and 2.34%, and reproducibility RSD values ranged between 1.46% and 3.72%. The applicability of this method was demonstrated in four margarine samples and it was compared with the method used as reference. In general, the results proved that the proposed method is suitable for the analysis of FAs since it has shown higher effectiveness in TFA analysis than the classic methods. Thus, it could be an effective tool for analysing dietary fats and oils in complex mixtures of food products for the monitoring of low levels of FAs and TFA, and the control of labelling authenticity.

Abstract P265: Plasma Phospholipid Trans Fatty Acids, Cardiovascular Diseases, and Total Mortality: The Cardiovascular Health Study

Introduction: Whereas trans fatty acids (TFAs) have generally been evaluated as a group, emerging evidence suggests that trans18:2, but not trans18:1 or trans16:1, isomers are especially adverse for health. Few studies have investigated how biomarkers of different TFA isomers relate to CVD or total mortality. Objective: To examine prospective associations of circulating trans16:1n9 (16:1n9t), total trans18:1 (18:1t, the sum of 18:1n5-12), and n9cis/n6trans, n9trans/n6cis, and n9trans/n6trans 18:2 (18:2ct, 18:2tc, 18:2tt) with incident CVD events and total mortality. Methods: We prospectively evaluated 2,788 adults in the Cardiovascular Health Study, age 72±5y, free of prevalent CVD, and having plasma phospholipid TFA measures from blood stored in 1992. CVD events and mortality were centrally adjudicated through 2010, including total mortality, CVD death, CHD death, nonfatal MI (NFMI), and ischemic stroke. Risk associated with each TFA was assessed using Cox proportional hazards adjusting for sociodemographics, lifestyle, dietary habits, prevalent diseases, and the 5 TFA mutually. Results: During 31,863 person-years, 1,681 deaths occurred including 581 CVD and 373 CHD deaths; as well as 383 NFMI and 328 ischemic strokes. 18:2ct was associated with higher CVD mortality (quintile 5 vs. 1 HR 1.48, 95%CI 0.98-2.23, p trend 0.04), but not total mortality or nonfatal CVD events. 18:2tc was related to higher NFMI (HR 1.69, 95%CI 1.06-2.69, p trend&lt;0.01), while 18:2tt was not significantly associated with mortality or CVD endpoints. Similarly, 16:1n9t was positively associated with NFMI (HR 2.96, 95%CI 1.80-4.88, p trend&lt;0.01), and ischemic stroke (HR 2.00, 95%CI 1.19-3.36, p trend 0.02), but not mortality endpoints. 18:1t was associated with lower CVD (HR 0.52, 95%CI 0.34-0.79, p trend=0.01) and CHD (HR 0.49, 95%CI 0.29-0.84, p trend 0.02) mortality, but these findings for 18:1t were substantially (~50%+) weakened when analyses did not mutually adjust for all 5 TFA, which were intercorrelated (r -0.08 to 0.78). Conclusions: Specific 18:2 TFA isomers, 18:2ct and 18:2tc but not 18:2tt, as well as 16:1n9t are prospectively associated with higher incidence of CVD events. 18:1t is associated with lower CVD risk, perhaps owing at least partly to co-adjustment for multiple correlated TFAs. The general specificity of all findings for CVD events, rather than total mortality or non-CVD mortality, is consistent with adverse physiologic effects of TFA on CVD risk factors. These results highlight the need for further investigation of effects and determinants of specific TFA subclasses and isomers.

Linolelaidic Acid Induces a Stronger Proliferative Effect on Human Umbilical Vein Smooth Muscle Cells Compared to Elaidic Acid

Trans fatty acids (TFA) have been considered as an independent risk factor of coronary heart disease, sudden death and insulin-resistance, and different TFA isomers may have different effects on the progression of cardiovascular diseases such as atherosclerosis. The aim of the study was to investigate the effects of two major TFA, elaidic acid and linolelaidic acid which have the same number of carbons but a different number and configuration of trans bonds, on the proliferation of human umbilical vein smooth muscle cells (HUVSMC). Methyl thiazolyl tetrazolium and flow cytometry assays showed that the cell proliferation rose to 115.37±0.39 and 117.5±0.57% and the cell number in the S phase of the cell cycle reached 27.7±0.7 and 25.8±2.8% when treated with 50μM elaidic acid and 20μM linolelaidic acid, respectively. Quantitative real-time reverse transcriptase-polymerase chain reaction and Western blotting analyses showed that the two TFA increased the mRNA and protein expression levels of PCNA, CDK2 and Cyclin E in HUVSMC. Moreover, gas chromatography analysis showed that the total PUFA level of HUVSMC was lower after treatment with the two TFA, especially n-3 PUFA. These results suggested that linolelaidic acid exhibited a stronger proliferative effect on HUVSMC than elaidic acid, and regulation of CDK2 and Cyclin E may be important for the effect of the TFA on atherosclerosis.

Trans Fatty Acids Affect Cellular Viability of Human Intestinal Caco-2 Cells and Activate Peroxisome Proliferator-Activated Receptors

Trans fatty acids (TFA) are hypothesized to have an impact not only on coronary heart diseases but also on the development of colon cancer. To analyze if TFA exhibit cellular and molecular effects which could be involved in colon tumor progression, cells of the human colorectal adenocarcinoma-derived cell line Caco-2 were treated with various TFA isomers differing in the number and position of trans double bonds. The TFA tested in this study did not increase cellular proliferation but displayed growth-inhibitory effects at concentrations higher than 500 μM. In case of the TFA isomer C18:3 t9, t11, t13, an IC50 value of 23 μM was estimated for cytotoxicity indicating a high cytotoxic potential of this compound. In addition to the cytotoxicity studies, the TFA isomers were tested for their ability to activate peroxisome proliferator-activated receptors (PPAR) by taking advantage of a PPAR-dependent reporter gene assay. In contrast to PPARγ that was not activated by the TFA isomers tested in this study, the substances were shown to moderately activate PPARα, and strong activation was observed for PPARδ. The putative impact of TFA on colon cancer development with respect to PPARδ activation is being discussed.

Assessment of Trans Fatty Acid Content in Widely Consumed Snacks by Gas Chromatography in a Developing Country

Trans fatty acids have adverse effects on health, so knowledge of their contents in foods would enable people to make informed food choices. TFA levels when not available in food composition tables make it difficult to estimate dietary intake. With the aim to analyze and identify the actual amount of trans fatty acid present in selected Indian fast food items, triplicate samples of six commonly consumed snacks as well as the oil used for preparing the same were collected from three different places. The separation of fatty acid was done using gas chromatography. Trans fatty acid isomers of oleic acid, linoleic acid and linolenic acid were identified in all food items. The predominant trans fatty acid present in all the food items was elaidic acid (18:1t9). The total trans fatty acids in different food items ranged from almost negligible to as high as 14.58 g/100g food. Different amount of TFA was found in same food category sourced from different outlets which is a challenge in making regulations aimed at TFA reduction so as to decrease health risk.

Trans-fatty acids, dangerous bonds for health? A background review paper of their use, consumption, health implications and regulation in France

Trans-fatty acids (TFAs) can be produced either from bio-hydrogenation in the rumen of ruminants or by industrial hydrogenation. While most of TFAs' effects from ruminants are poorly established, there is increasing evidence that high content of industrial TFAs may cause deleterious effects on human health and life span. Indeed, several epidemiological and experimental studies strongly suggest that high content of most TFA isomers could represent a higher risk of developing cardiovascular diseases by a mechanism that lowers the "good HDL cholesterol" and raises the "bad LDL cholesterol." With respect to the general precautionary principle and considering the existence of an international policy consensus regarding the need for public health action, some industrialized countries, such as France, are still not sufficiently involved in preventive strategies that aim to efficiently reduce TFAs content and TFAs consumption and produce alternative healthier fat sources. In this manuscript, we provide an overview about TFAs origins, their use and consumption among French population. We also discuss their potential human health implications as well as the preventive and regulatory measures undertaken in France.

Intake of ruminant trans fatty acids and changes in body weight and waist circumference.

Follow-up studies have suggested that total intake of trans fatty acids (TFA) is a risk factor for gain in body weight and waist circumference (WC). However, in a cross-sectional study individual TFA isomers in adipose tissue had divergent associations with anthropometry. Our objective was to investigate the association between intake of TFA from ruminant dairy and meat products and subsequent changes in weight and WC. Furthermore, potential effect modification by sex, age, body mass index and WC at baseline was investigated. Data on weight, WC, habitual diet and lifestyle were collected at baseline in a Danish cohort of 30,851 men and women aged 50-64 years. Follow-up information on weight and WC was collected 5 years after enrolment. The associations between intake of ruminant TFA (R-TFA) and changes in weight and WC were analysed using multiple linear regression with cubic spline modelling. Intake of R-TFA, both absolute and energy-adjusted intake, was significantly associated with weight change. Inverse associations were observed at lower intakes with a levelling-off at intakes >1.2 g/day and 0.4 energy percentage (E %). Absolute, but not energy-adjusted, intake of R-TFA was significantly associated with WC change. An inverse association was observed at lower intakes with a plateau above an intake of 1.2 g/day. The present study suggests that intake of R-TFA is weakly inversely associated with changes in weight, whereas no substantial association with changes in WC was found.

Effects of 16-carbon and 18-carbon trans isomeric fatty acids in the perinatal period

Effects of 16-carbon and 18-carbon trans isomeric fatty acids in the perinatal period

Inverse Association between trans Isomeric and Long-Chain Polyunsaturated Fatty Acids in Pregnant Women and Their Newborns: Data from Three European Countries

Background:trans unsaturated fatty acids are thought to interfere with essential fatty acid metabolism. To extend our knowledge of this phenomenon, we investigated the relationship between trans isomeric and long-chain polyunsaturated fatty acids (LCPUFA) in mothers during pregnancy and in their infants at birth. Methods: Fatty acid composition of erythrocyte phosphatidylcholine (PC) and phosphatidylethanolamine (PE) was determined in Spanish (n = 120), German (n = 78) and Hungarian (n = 43) women at the 20th and 30th week of gestation, at delivery and in their newborns. Results: At the 20th week of gestation, the sum of trans fatty acids in PE was significantly (p < 0.01) lower in Hungarian [0.73 (0.51), % wt/wt, median (IQR)] than in Spanish [1.42 (1.36)] and German [1.30 (1.21)] women. Docosahexaenoic acid (DHA) values in PE were significantly (p < 0.01) higher in Hungarian [5.65 (2.09)] than in Spanish [4.37 (2.60)] or German [4.39 (3.3.2)] women. The sum of trans fatty acids significantly inversely correlated to DHA in PCs in Spanish (r = –0.37, p < 0.001), German (n = –0.77, p < 0.001) and Hungarian (r = –0.35, p < 0.05) women, and in PEs in Spanish (r = –0.67, p < 0.001) and German (r = –0.71, p < 0.001), but not in Hungarian (r = –0.02) women. Significant inverse correlations were seen between trans fatty acids and DHA in PEs at the 30th week of gestation (n = 241, r = –0.52, p < 0.001), at delivery (n = 241, r = –0.40, p < 0.001) and in cord lipids (n = 218, r = –0.28, p < 0.001). Conclusion: Because humans cannot synthesize trans isomeric fatty acids, the data obtained in the present study support the concept that high maternal trans isomeric fatty acid intake may interfere with the availability of LCPUFA both for the mother and the fetus.

Ecological-Level Associations Between Highly Processed Food Intakes and Plasma Phospholipid Elaidic Acid Concentrations: Results From a Cross-Sectional Study Within the European Prospective Investigation Into Cancer and Nutrition (EPIC)

Elaidic acid is the main unnatural trans fatty acid isomer occurring during partial hydrogenation of vegetable oils used as ingredients for the formulation of processed foods. The main objective is to assess associations between processed food intakes and plasma phospholipid elaidic acid concentrations within the European Prospective Investigation into Cancer and Nutrition study. A cross-sectional study was used to determine fatty acid profiles in 3,003 subjects from 16 centers. Single 24-h dietary recalls (24-HDR) were collected using a standardized computerized interview program. Food intakes were computed according to their degree of processing (moderately/nonprocessed foods, processed staple foods, highly processed foods). Adjusted ecological and individual correlations were calculated between processed food intakes and plasma elaidic acid levels. At the population level, mean intakes of highly processed foods were strongly correlated with mean levels of plasma elaidic acid in men (P = 0.0016) and in women (P = 0.0012). At the individual level, these associations remained but at a much lower level in men (r = 0.08, P = 0.006) and in women (r = 0.09, P = 0.0001). The use of an averaged 24-HDR measure of highly processed food intakes is adequate for predicting mean levels of plasma elaidic acid among European populations.

Starch and oil in the donor cow diet and starch in substrate differently affect the in vitro ruminal biohydrogenation of linoleic and linolenic acids

Trans isomers of fatty acids exhibit different health properties. Among them, trans-10,cis-12 conjugated linoleic acid has negative effects on milk fat production and can affect human health. A shift from the trans-11 to the trans-10 pathway of biohydrogenation (BH) can occur in the rumen of dairy cows receiving high-concentrate diets, especially when the diet is supplemented with highly unsaturated fat sources. The differences of BH patterns between linoleic acid (LeA) and linolenic acid (LnA) in such ruminal conditions remain unknown; thus, the aim of this work was to investigate in vitro the effects of starch and sunflower oil in the diet of the donor cows and starch level in the incubates on the BH patterns and efficiencies of LeA and LnA. The design was a 4 × 4 Latin square design with 4 cows, 4 periods, and 4 diets with combinations of 21 or 34% starch and 0 or 5% sunflower oil. The rumen content of each cow during each period was incubated with 4 substrates, combining 2 starch levels and either LeA or LnA addition. Capillary electrophoresis single-strand conformation polymorphism of incubates showed that dietary starch decreased the diversity of the bacterial community and the high-starch plus oil diet modified its structure. High-starch diets poorly affected isomerization and first reduction of LeA and LnA, but decreased the efficiencies of trans-11,cis-15-C18:2 and trans C18:1 reduction. Dietary sunflower oil increased the efficiency of LeA isomerization but decreased the efficiency of trans C18:1 reduction. An interaction between dietary starch and dietary oil resulted in the highest trans-10 isomers production in incubates when the donor cow received the high-starch plus oil diet. The partition between trans-10 and trans-11 isomers was also affected by an interaction between starch level and the fatty acid added to the incubates, showing that the trans-10 shift only occurred with LeA, whereas LnA was mainly hydrogenated via the more usual trans-11 pathway, whatever the starch level in the substrate, although the bacterial communities were not different between LeA and LnA incubates. In LeA incubates, trans-10 isomer production was significantly related to the structure of the bacterial community.