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PubMed2002

Adipose tissue biomarkers of fatty acid intake.

BACKGROUND: Biomarkers can provide a more accurate measure of long-term intake than can dietary questionnaires. OBJECTIVE: The objective was to identify which adipose tissue fatty acids are suitable biomarkers of intake as assessed with a validated food-frequency questionnaire. DESIGN: Costa Rican men with a mean (+/- SD) age of 56 +/- 11 y (n = 367) and women aged 60 +/- 10 y (n = 136) completed a 135-item food-frequency questionnaire and provided an adipose tissue sample. Fifty fatty acids were identified by capillary gas chromatography. Correlation coefficients were calculated after adjustment for age, sex, body mass index, and smoking status. RESULTS: The best adipose tissue marker for total intake of saturated fatty acids was 15:0 + 17:0 (r = 0.18). Both 15:0 and 17:0 were also the best correlates of dairy product intake (r = 0.31 for each). The diet-adipose tissue correlations for n-3 fatty acids were r = 0.34 for 18:3, r = 0.15 for 20:5, and r = 0.18 for 22:6. Fish intake correlated significantly with these adipose tissue n-3 fatty acids. Dietary and adipose tissue n-6 fatty acids were highly correlated: 18:2 (r = 0.58) and 18:3 (r = 0.24). The best indicators of total trans fatty acid intake were ct18:2n-6 and tc18:2n-6 (r = 0.58 for each); total 18:1 trans fatty acid (r = 0.45) and 16:1 trans fatty acid (r = 0.16) were the next best indicators. CONCLUSIONS: Adipose tissue is a suitable biomarker of dietary fatty acid intake, particularly for n-3 and n-6 cis polyunsaturated fatty acids and trans fatty acids. Ideally, adipose tissue and dietary questionnaires should complement, rather than substitute for, each other in epidemiologic studies.

Adipose Tissue↗

PubMed1984

Large intestinal carcinogenesis. I. Promotional effect of dietary fatty acid isomers in the rat model.

For evaluation of the promotional effects of dietary trans-fatty acids on large intestinal carcinogenesis, 120 inbred female F344 rats were divided into 6 groups and fed a 25% elaidic acid diet, a 25% oleic acid diet, or a regular (4.5% fat) chow diet. Ninety animals, 30 per dietary group, received weekly im injections of azoxymethane (2 mg/kg; CAS: 25843-45-2). None of the 30 saline-injected control animals, 10 per dietary group, fed any of the three diets developed tumors. There were twice as many animals with adenocarcinoma of the large intestine from the trans-fatty acid diet group as compared with either the cis-fatty acid diet group or regular diet groups. Chi-square analysis showed that the difference between the incidence of large intestinal carcinomas was not significant between the cis- and trans-fatty acid diets. The difference between the regular diet and trans-fatty acid diet groups was not significant at the 5% level (P = .08). A higher, but nonstatistically significant, incidence of nephroblastomas and squamous ear duct neoplasms was also observed in carcinogen-treated animals maintained on each of the high-fat diets as compared with the incidence of both in treated animals fed the regular chow diet.

Animals↗

PubMed2004

n-6 Docosapentaenoic acid is not a predictor of low docosahexaenoic acid status in Canadian preschool children.

BACKGROUND: The n-3 fatty acid docosahexaenoic acid (DHA; 22:6n-3) is important for neural and visual functional development. In animals, 22:6n-3 deficiency is accompanied by increased docosapentaenoic acid (DPA; 22:5n-6), which suggests that the ratio of 22:6n-3 to 22:5n-6 could be a useful biochemical marker of low n-3 fatty acid status. The n-3 fatty acid status of preschool children has not been described, and data are lacking on whether low 22:6n-3 is accompanied by high 22:5n-6 in humans. OBJECTIVE: We determined n-3 fatty acid status and investigated the relation between 22:6n-3 and 22:5n-6 in children. DESIGN: In Canadian children aged 18-60 mo (n = 84), the n-3 and n-6 fatty acid status of erythrocyte phosphatidylethanolamine was measured, and dietary fat intake was estimated by using a food-frequency questionnaire. RESULTS: The mean (+/- SEM) 22:6n-3 concentration in erythrocyte phosphatidylethanolamine among children was 3.06 +/- 0.13 g/100 g fatty acids (5th-95th percentiles: 1.43-5.79 g/100 g fatty acids). Concentrations of 22:5n-6 increased with increasing 22:6n-3 concentrations in erythrocyte phosphatidylethanolamine (P < 0.01). Mean intakes of linoleic acid (18:2n-6), linolenic acid (18:3n-3), and trans fatty acids were 3.6 +/- 0.2%, 0.7 +/- 0.5%, and 2.0 +/- 1.3%, respectively. Phosphatidylethanolamine 22:6n-3 and 22:5n-3 concentrations were inversely related to the intakes of 18:2n-6 and trans fatty acids, but not to those of total fat or n-3 fatty acids. CONCLUSIONS: The concentration of 22:5n-6 is not a useful biochemical marker of low n-3 fatty acid intake or status in the membrane phosphatidylethanolamine of preschool children. High intakes of 18:2n-6 and trans fatty acids could compromise the incorporation of 22:6n-3 into membrane phospholipids.

Biomarkers↗

PubMed1987

Saturated and trans-unsaturated fatty acids elicit high levels of superoxide generation in intact and cell-free preparations of neutrophils.

Saturated and trans-unsaturated fatty acids, such as laurate and elaidate, elicited O2- generation in intact porcine and human neutrophils and also in a cell-free preparation of porcine neutrophils. The activities thus induced were comparable to those induced by cis-unsaturated fatty acids. However, the activation by saturated or trans-unsaturated fatty acids was depressed almost completely in the presence of Ca2+ at around 1 mM, which is usually contained in the media for phagocytes. In contrast, the activation by cis-unsaturated fatty acids such as arachidonate was scarcely affected by Ca2+. These findings appear to demand reevaluation of the effects of long chain fatty acids on the respiratory burst system in phagocytes.

Animals↗

PubMed2005

Contribution of foods to trans unsaturated fatty acid intake in a group of Irish adults.

OBJECTIVE: To assess fat intake with particular focus on trans unsaturated fatty acid (TUFA) intake and the major sources of TUFA among Irish individuals using a Fat Intake Questionnaire (FIQ), designed specifically for an Irish context. SUBJECTS AND METHODS: A total of 105 healthy volunteers (43 females, 62 males; aged 23-63 years) were recruited from Dublin Airport Medical centre, Republic of Ireland. Dietary intake was assessed using an 88 food item/food group semi-quantitative FIQ, which was developed and validated for the Irish population. RESULTS: Mean energy intake was 10.6 MJ day(-1), and 34% was provided by fat. Saturated, monounsaturated, polyunsaturated, trans unsaturated fatty acids and linoleic acid contributed 13%, 10%, 6%, 2% and 5% of energy respectively. Mean TUFA intake was 5.4 g day(-1) (range 0.3-26). Margarine spreads provided the majority of TUFAs (1.93 g day(-1)), but the contribution was significantly greater for men compared with women (2.35 g day(-1) versus 1.33 g day(-1); P = 0.024). Milk and meat also contributed more to TUFA intake for men compared with women, but confectionery was a significantly greater contributor for women (8.6% versus 3.1% respectively, P = 0.01). CONCLUSIONS: Although the mean TUFA intake of the total group was 5.4 g day(-1) and was within current dietary recommendations (2% energy intake), some individuals had intakes as high as 26 g day(-1). Public health efforts are therefore required to reduce TUFA intake in those individuals with high intakes.

Adult↗

PubMed2002

Trans polyunsaturated fatty acids have more adverse effects than saturated fatty acids on the concentration and composition of lipoproteins secreted by human hepatoma HepG2 cells.

The objective of this study was to assess the relative long-term effects of linoleic (cis, cis 18:2), linolelaidic (trans, trans 18:2), and palmitic (16:0) acids on hepatic lipoprotein production in HepG2 cells. All fatty acids increased the mass of triglycerides (TG) in the medium and the incorporation of [(3)H]-glycerol into secreted TG; the increase was more pronounced with linoleic acid than with linolelaidic and palmitic acids. The net accumulation in the medium of apolipoprotein (apo) A-I was not affected by the fatty acids tested and moderate changes in that of apoB resulted in apoB/apoA-I mass ratios of 1.05, 1.27 and 0.86 with linoleic, linolelaidic and palmitic acids, respectively. The incorporation of [(14)C]-acetate into cellular plus secreted total sterols was 9.1%, 33.6% and 17.4% of total [(14)C]-labeled lipids with linoleic, linolelaidic and palmitic acids, respectively. Relative to linoleic acid, palmitic acid, and to a greater extent (P < 0.05) linolelaidic acid, increased the secretion and cellular accumulation of [(14)C]-labeled free cholesterol (FC) and cholesteryl esters and decreased those of TG and phospholipids (PL). Compared with linoleic acid, linolelaidic acid increased LDL-cholesterol (C) and HDL-C by 154% (P < 0.001) and 50% (P = 0.016), respectively, whereas palmitic acid increased LDL-C by 17% (P > 0.1) and did not affect HDL-C. The LDL-C to HDL-C ratios were 0.70, 1.18 and 0.96 with linoleic, linolelaidic and palmitic acids, respectively. These differences were not due to altered LDL receptor activity. The PL to C ratios of HDL particles were 1.61, 0.40 and 0.77 with linoleic acid, linolelaidic acid and palmitic acid, respectively. These results suggest that relative to cis polyunsaturated and saturated fatty acids, trans PUFA more adversely affect the concentration and composition of apoA-I- and apoB-containing lipoproteins secreted by HepG2 cells.

Apolipoprotein A-I↗

PubMed1978

Incorporation, metabolism and positional distribution of trans-unsaturated fatty acids in developing and mature brain. Comparison of elaidate and oleate administered intracerebrally.

Mixtures of [1-14C]elaidic acid and [9,10-3H]oleic acid, as well as [1-14C]elaidic or [1-14C]oleic acid alone, were administered by intracerebral injection to 10-day old and adult rats to examine the relative incorporation and metabolism of trans- and cis-monounsaturated fatty acids in developing and mature brain. Rates and extents of total incorporation of label from trans- and cis-acid into complex lipids were similar. Maximum labeling of the neutral lipid, mainly triacylglycerol and cholesterol, occurred prior to 4 h after injection whereas phospholipid, mainly choline phosphoglyceride, was maximally labeled at 4--8 h after injection. The decrease in labeled phospholipid from 24 to 90 h was greater with elaidate than with oleate. At 8 h labeled elaidic acid was preferentially esterified in the 1-position of all phosphoglycerides whereas labeled oleic acid, in contrast to the positional distribution of endogenous oleate, was randomly distributed. Label from elaidate found in palmitate increased with time to 26% of the total recovered label by 48 h. Thus, although some of the trans-fatty acid is oxidized and its labeled carbon is redistributed, most is incorporated unaltered into complex lipid of brain at rates similar to those for its cis-isomer. The developing central nervous system, therefore, does not metabolically exclude the trans-acid, elaidic acid, from membrane lipids.

Animals↗

PubMed1978

Trans-isomeric fatty acids present in West German margarines, shortenings, frying and cooking fats.

Fatty acid patterns were determined in 83 brands of margarine, 9 brands of low-calorie margarine and 18 brands of shortening, frying and cooking fat purchased at random from the retail marker in the Federal Republic of Germany in 1973/1974, and a second time in 1976. As a result of gas-liquid chromatographic analyses on a Silar 10 C coated packed column, complemented in some cases by the values recorded on a highly selective SP 2340 capillary column, trans-octadecenoic acids ranging from 53.2 to 0.1% were measured. None of the products examined was completely free of trans-fatty acids. High values of trans-octadecenoate were always accompanied by positional isomers of cis-octadecenoate, by 9trans,12trans-octadecadienoate and by 9cis,12trans-octadecadienoate and 9trans,12cis-octadecadienoate. Furthermore, two mixed geometric isomers derived from linolenic acid (probably 9cis,12cis,15trans-octadecatrienoate and 9trans,12cis,15cis-octadecatrienoate) could be identified, provided that the individual brand contained sufficient linolenic acid. Following partial hydrogenation, transhexadecenoate, 0.1 to 0.2%, was detected in some of the edible fats.

Chromatography, Gas↗

PubMed1980

[Implications of the incorporation of transisomers of unsaturated fatty acids into cell membranes].

The incorporation of dietary trans fatty acids is shown into intestinal brush border and heart mitochondrial membranes obtained from rats fed with either partially hydrogenated soybean oil or with a synthetic triglyceride containing elaidic or linelaidic acid. The distribution of dietary linelaidate in the major phospholipid classes from inner membranes of mitochondria is determined. Heart mitochondria from normal rats and linelaidic acid fed rats are compared with respect to their swelling rate and their oxidative phosphorylation. The influence of dietary linelaidate on the activity of some brush border-associated enzymes is also studied. On the basis of the authors' observations and those made by others with microorganism cels or models of biological membranes (liposomes and monomolecular films), the possible implications of trans fatty acids incorporation on membrane functions are reviewed.

Animals↗

PubMed1998

The relation between dietary intake and adipose tissue composition of selected fatty acids in US women.

We compared fatty acid amounts in adipose tissue with fatty acid intake calculated from 2 separate weeks of diet recording and two food-frequency questionnaires for 140 participants in the Nurses' Health Study. Our results showed that the amounts of polyunsaturated and trans fatty acids in adipose tissue reflect dietary intake and confirm those of previous studies. The correlation between the polyunsaturated fatty acid content of adipose tissue and polyunsaturated fatty acid intake from the average of the two food-frequency questionnaires was 0.40; this correlation for trans fatty acids was also 0.40. Linolenic acid amounts in adipose tissue were also moderately correlated with intake from the average of the food-frequency questionnaires (r = 0.34). An estimate of trans fatty acid intake from vegetable sources correlated much more strongly with adipose trans fatty acids than did an estimate of trans fatty acids from animal sources. Adipose tissue aspirates can be used to indicate intake of exogenous fatty acids.

Adipose Tissue↗

PubMed1994

Synthesis of trans unsaturated fatty acids in Pseudomonas putida P8 by direct isomerization of the double bond of lipids.

The phospholipids of Pseudomonas putida P8 contain monounsaturated fatty acids in the cis and trans configuration. Cells of this phenol-degrading bacterium change the proportions of these isomers in response to the addition or elimination of a membrane active compound such as 4-chlorophenol. This study undoubtedly reveals that the cis unsaturated fatty acids are directly converted into trans isomers without involvement of de novo synthesis of fatty acids. Oleic acid, which cannot be synthesized by this bacterium, was incorporated as a cis unsaturated fatty acid marker in the membrane lipids of growing cells. The conversion of this fatty acid into the corresponding trans isomer was demonstrated by gas chromatographic-mass spectrometric analysis and use of 14C-labeled oleic acid. Separation and isolation of the cellular membranes showed that the fatty acid isomerase is located in the cytoplasmic membrane of P. putida P8.

Carbohydrate Sequence↗

PubMed2004

Fatty acids in Chinese edible oils: value of direct analysis as a basis for labeling.

Edible oil is an important element in the diet of most transitional countries; nevertheless, little is known about the fatty acid composition of these oils. We examined the consumption of edible oils and the fatty acid composition of these oils obtained from a market survey conducted in seven Chinese provinces and in Beijing. Three days of measured household food intake from the 1997 China Health and Nutrition Survey households provided data on the consumption of edible oils. Edible oils sold in the capital cities of eight provinces were purchased. One hundred twenty-six samples, representing 14 different oils according to their labels, were assayed for their fatty acid content in 2001. Fatty acids were analyzed by standard gas chromatographic methods. More than 76% of households in China consume edible oil, providing an average of 29.6 g of edible oil per day to persons aged two years or older. Rapeseed was consumed by one-quarter of individuals. Rapeseed is rich in C22:1n9 cis (erucic acid). About 33% of edible oils differed from their labeled identification. Rapeseed oil, identified by the presence of C22:1n9 (erucic acid), was most frequently not labeled as such. In another 28% of the samples, trans isomers of linolenic acid were detected. Deviations from the label identification were more common in southern than in northern provinces. Regulations requiring complete labeling of mixed edible oils in China might help prevent unintentional consumption of fatty acids associated with adverse health outcomes. In particular, consumption of erucic acid and trans fatty acids might be reduced. The results suggest the need for closer control of food oil labeling in China, especially in the South.

China↗

PubMed2003

Trans-unsaturated fatty acids and acrylamide in food as potential atherosclerosis progression factors. Based on own studies.

Atherosclerosis is a chronic pathological process and it is generelly accepted that lipids, coagulation and inflammatory factors play an important role in its development. Environmental factors such as bed diet and cigarette smoking strongly stimulate initation and progression of atherosclerotic changes in the artery wall. It has been recognized that deeply processed food may be a source of various factors potentiating processes related to atherosclerosis development among which inflammatory processes are of great importance. The aim of our studies was to find out if the trans-unsaturated fatty acids as well as acrylamide present in foods have the potential to provoke pro-inflammatory states in the body and enhance atherosclerosis risk. The results of our in vitro studies have shown that trans fatty acids cause a significant increase in secretion of reactive oxygen species, interleukin-6, tumor necrosis factor a and metalloproteinase-9, and enhance apoptosis. It indicates that in vivo trans-fatty acids may distroy the endothelium integrity and cause plaque rupture. Our in vivo studies in the group of healthy volunteers have shown that the consumption of potato chips rich in acrylamide cause the significant increase in plasma C-reactive protein and homocysteine concentrations. Enhanced CRP and HCY levels are accepted markers of enhanced atherosclerosis risk.

Acrylamide↗

PubMed2001

alpha-Linolenic acid intake is not beneficially associated with 10-y risk of coronary artery disease incidence: the Zutphen Elderly Study.

BACKGROUND: Data on the relation between alpha-linolenic acid intake and coronary artery disease (CAD) are limited. Other dietary components appear to modify the reported relation between alpha-linolenic acid intake and CAD. OBJECTIVE: We examined whether dietary alpha-linolenic acid intake was inversely associated with risk of CAD. DESIGN: We prospectively studied 667 men aged 64-84 y from the Zutphen Elderly Study who were free of CAD at baseline. Dietary intake was assessed by using a cross-check dietary history method. RESULTS: During the 10-y follow-up, we documented 98 cases of CAD. After adjustment for age, standard coronary risk factors, and intake of trans fatty acids and other nutrients, alpha-linolenic acid intake was not significantly associated with CAD risk. The relative risk of CAD for the highest compared with the lowest tertile of alpha-linolenic acid intake was 1.68 (95% CI: 0.86, 3.29). alpha-Linolenic acid intake from sources containing trans fatty acids was also nonsignificantly, yet positively, associated with CAD risk. alpha-Linolenic acid intake from foods that did not contain trans fatty acids was not associated with CAD risk, the relative risk of CAD for the highest compared with the lowest tertile was 1.15 (95% CI: 0.63, 2.11). CONCLUSION: We did not observe a beneficial effect of dietary alpha-linolenic acid intake on the risk of 10-y CAD incidence. Investigating this hypothesis was complicated by the association between intakes of alpha-linolenic acid and trans fatty acids. Given the results of current prospective studies, a protective cardiac effect of alpha-linolenic acid is questionable.

Aged↗

PubMed1986

Isomeric fatty acids in the US diet: levels and health perspectives.

Data on market size, market share, and compositional changes of various products made from partially hydrogenated fats and oils were used to estimate current, previous, and predicted levels of trans fatty acids in the US diet. Recent literature and various perceptions of the toxicological, physiological, and nutritional effects of trans fatty acids were reviewed. Trans acid availability has changed little during the last 15-20 yr and currently is estimated to be approximately 7.6 g X person-1 X day-1. Modest decreases in total fat intake, including trans fatty acid intake, may occur in the future if consumers adopt certain dietary recommendations. We believe that concerns about possible relationships of trans fatty acids to development of atherosclerotic disease or cancer are not supported by reliable data. Numerous literature accounts support the conclusion that trans fatty acids do not pose any harm to humans or animals consuming a balanced diet containing adequate linoleic acid.

Animals↗

PubMed1994

Plasma cholesteryl ester transfer protein activity is increased when trans-elaidic acid is substituted for cis-oleic acid in the diet.

The trans isomer of oleic acid (elaidic acid) increases low density lipoprotein (LDL) cholesterol and decreases high density lipoprotein (HDL) cholesterol in man. One possible mechanism for this effect is that trans fatty acids increase plasma cholesteryl ester transfer protein (CETP) activity. We examined the effect of dietary trans fatty acids on activity of this protein in plasma from 27 men in a double blind crossover comparison. The background diet, containing 15% energy as fat from dairy products, meat, bread and cereals, was supplemented with oleic or elaidic acid providing a further 20% energy. The elaidic supplement provided about 6% energy as trans fatty acid. Activity of CETP in plasma was significantly higher (P < 0.001) after the elaidic acid-rich diet (23.95 +/- 1.26%) compared with the diet enriched with oleic acid (19.61 +/- 0.89%). A significant correlation between the change in plasma trans 18:1 fatty acids and the change in plasma CETP activity (r = 0.58, P < 0.002) was independent of changes in LDL-cholesterol. The increase in CETP activity was in turn significantly correlated with a fall in HDL-cholesterol among subjects during the elaidic acid-rich period (r = -0.57, P < 0.01). We have shown that CETP demonstrates substrate specificity and that the increase in activity with dietary trans fatty acids may contribute to a more atherogenic lipoprotein profile.

Adult↗

PubMed2005

5E, 8Z, 11Z, 14Z-eicosatetraenoic acid, a novel trans isomer of arachidonic acid, causes G1 phase arrest and induces apoptosis of HL-60 cells.

Trans arachidonic acid isomers (trans-AA) constitute a new group of trans fatty acids (trans-FA) generated in vivo via endogenous cis-trans isomerization stimulated by the NO2 radical. Because both NO2 and trans-FA have been implicated as causative factors in cancer, we studied the effect of the trans-AA isomers on proliferation and viability of human promyelocytic (HL-60) cells. The four trans arachidonic (trans-AA) acid isomers synthesized by us have been presently tested with respect to their competence to affect the proliferation and viability of human promyeolocytic HL-60 cells in culture. The data demonstrate that one of the isomers, 5,6-trans-AA, showed distinct activity by targeting cell progression through the cell cycle and inducing apoptosis. The effects were time- and concentration-dependent: the cytostatic effect of 5E-AA was observed at 10 microM following 72 h of treatment. This effect was manifested as a perturbation of cell progression through G1 phase, indicating the 'on' activation of the G1 checkpoint as evidenced by the flow- and laser scanning-cytometry techniques. Apoptotic cells were identified by comparison of their morphology, DNA fragmentation, caspase activation and collapse of mitochondrial potential with control cells. These observations suggested that 5E-AA induced a mitochondrial pathway of apoptosis. There was no evidence of cell-cycle phase specificity in induction of apoptosis by 5E-AA, as the cells showing highly fragmented DNA or caspase-3 activation were distributed in all phases of the cycle. The data suggest that 5E-AA may have at least two targets: one that is cell-cycle specific and associated with the observed arrest in the G1 phase and another, unrelated to the cell cycle, which is responsible for triggering apoptosis indiscriminately, regardless of cycle phase I.

Apoptosis↗

PubMed2003

Trans unsaturated fatty acids are less oxidizable than cis unsaturated fatty acids and protect endogenous lipids from oxidation in lipoproteins and lipid bilayers.

Epidemiological data suggest that dietary trans unsaturated fatty acids increase the risk of heart disease; however, the underlying mechanisms are unclear. In this study, we investigated one possible mechanism, namely, their effect on LDL oxidation. Supplementation of LDL with 10% 16:1 trans-cholesteryl ester (CE) inhibited the oxidation compared to that with 16:1 cis-CE. Total replacement of core lipids with 18:2 trans,trans-CE decreased the rate of LDL oxidation by 19% compared to replacement with 18:2 cis,cis-CE. When the surface phosphoglycerides were replaced with either 16:0-18:2 cis,cis-phosphatidylcholine (PC) or 16:0-18:2 trans,trans-PC, the latter was found to inhibit the rate and increase the lag time of oxidation to a greater extent than the former. To confirm these findings, we studied the oxidation of PC liposomes by assessing the formation of conjugated dienes or the degradation of a fluorescently labeled PC. By both methods, the 16:0-18:2 trans,trans-PC exhibited greater resistance to oxidation than the 16:0-18:2 cis,cis-PC. Eliminating the fluidity differences did not completely eliminate the differences in oxidation rates, suggesting that the trans double bond is inherently resistant to oxidation. The composition of the conjugated hydroperoxy products formed after oxidation differed markedly for the two 18:2 isomers. Supplementation of 16:0-18:2 cis,cis-PC liposomes with 20 mol % di16:1 trans-PC retarded oxidation rates to a greater extent than supplementation with di16:1 cis-PC. These studies show that dietary trans unsaturated fatty acids decrease the rate of lipid peroxidation, an effect that may mitigate the atherogenic effect of these fatty acids.

Alkadienes↗