Plasma Trans-fatty Acids Research Articles

Trans-fatty acids in New Zealand patients with coronary artery disease

Dietary surveys indicate that New Zealanders have a low intake of trans-fatty acids (TFA) with little derived from industrial sources. This observational cross-sectional study in New Zealand patients with surgical coronary artery disease assesses the plasma levels of TFA and the association of TFA levels with clinical markers of vascular disease. 390 patients with severe coronary artery had fasting blood tests taken. Plasma levels of four TFA derived from hydrogenated vegetable oils and ruminant animal products were measured by gas chromatography. Relations between plasma TFA levels and the recent occurrence of myocardial infarction, the presence of polyvascular disease, and serum levels of C-reactive protein (CRP) were assessed. The median TFA level was 0.85% by weight of total fatty acids (IQR 0.59-1.79%), with skewed distribution to the right. For the lowest (<0.74%), middle (0.74-1.07%), and highest (>1.07%) thirds of total TFA, respectively, the proportion of patients with polyvascular disease was 10%, 16%, and 27% (p = 0.0004). Plasma CRP also increased by tertile of TFA (median 2.0, 2.9, 3.2 mg/l, p = 0.007). The association with polyvascular diseases and CRP remained significant after adjustment for risk factors. Significant associations were present between plasma TFA from both ruminant and hydrogenated vegetable oil sources and these markers of cardiovascular risk. There is an association between relatively low plasma levels of total TFA, mostly derived from ruminant sources, and an increased risk of polyvascular disease and increased CRP in patients with severe coronary artery disease. These high-risk patients may benefit from a targeted approach to minimize all sources of TFA in the diet.

Trans-Fatty Acids in New Zealand Patients with Coronary Artery Disease

Background: Dietary surveys indicate that New Zealanders have a low intake of trans-fatty acids (TFA) with little derived from industrial sources. This observational cross-sectional study in New Zealand patients with surgical coronary artery disease assesses the plasma levels of TFA and the association of TFA levels with clinical markers of vascular disease.Methods: 390 patients with severe coronary artery had fasting blood tests taken. Plasma levels of four TFA derived from hydrogenated vegetable oils and ruminant animal products were measured by gas chromatography. Relations between plasma TFA levels and the recent occurrence of myocardial infarction, the presence of polyvascular disease, and serum levels of C-reactive protein (CRP) were assessed.Results: The median TFA level was 0.85% by weight of total fatty acids (IQR 0.59–1.79%), with skewed distribution to the right. For the lowest ( 1.07%) thirds of total TFA, respectively, the proportion of patients with...

N-3 Fatty acids prevent whereas trans-fatty acids induce vascular inflammation and sudden cardiac death

n-3 PUFA have well-recognised cardio-beneficial effects. In contrast, premature coronary deaths are associated with consumption of high levels of trans-fatty acids (TFA). The present study determined the effects of n-3 PUFA and TFA on sudden cardiac death and vascular inflammation. A rat coronary ligation model was used to study the effect of fatty acids on sudden cardiac death, whereas a mouse femoral artery ligation model was used to study compensatory vascular remodelling. Human aortic endothelial cells (HAEC) were utilised for the in vitro studies to investigate expression of inflammatory molecules. Feeding animals an n-3 PUFA-enriched diet caused a sevenfold increase in plasma n-3 PUFA compared with that of the TFA-fed group, whereas a TFA-enriched diet caused a 2.5-fold increase in plasma TFA compared with the n-3 PUFA group. Animals on a TFA diet had a lower survival rate due to sudden cardiac death and exhibited variable degrees of aortic atherosclerotic lesions. Animals on a TFA diet had diminished hindlimb collateral growth, whereas animals on the n-3 PUFA diet exhibited extensive collateral growth about ligated regions. HAEC treated with TFA (trans-18 : 2) showed significantly increased expression of intracellular adhesion molecule-1 and nitrosylation of cellular proteins than those treated with DHA (n-3 PUFA, 22 : 6). The in vivo study demonstrates that, in contrast to TFA, n-3 PUFA improve animal survival after myocardial infarction, prevent development of atherosclerotic lesions and stimulate compensatory vascular remodelling. The in vitro study demonstrates that TFA induce, while n-3 PUFA prevent, vascular inflammation.

Postprandial response of trans fatty acids in prepubertal obese children

To evaluate the intake, plasma concentrations and postprandial response of trans fatty acids in obese and control children at prepubertal age in order to detect potential associations with childhood obesity. Case-control study, clinical dietary intervention with a 428 kcal standardized breakfast and longitudinal 3 h postprandial follow-up for trans fatty acid plasma levels. Fifty-four children aged 6-13 years of both sexes, 34 obese (body mass index >97th percentile for age and sex) and 20 non-obese (control group) at prepubertal period (Tanner I). Various anthropometric parameters and sex hormones, fasting insulin and glucose, estimation of dietary trans fatty acid intake and their plasma quantitation in fasting conditions, and for 3 h following intake of a standardized breakfast. Dietary trans fatty acid intake was less than 0.4% of total energy in both groups, with a trend towards higher intake in obese children. Fasting plasma trans fatty acid concentrations and percentages were similar in both groups. However, trans fatty acid levels at +3 h were significantly higher than at 0 h in obese children, but not in controls (obese, 0 h: 2.38+/-0.29; 3 h: 3.62+/-0.45; controls, 0 h: 2.29+/-0.24; 3.14+/-0.49 mg/dl); cis monounsaturated fatty acid concentrations were not significantly affected by the postprandial interval. Obese children exhibited hyperinsulinemia and insulin resistance; however, trans fatty acid intake or their plasma levels were not associated with them. There is a low intake of trans fatty acids in Southern Spanish children, which is supported by their low concentrations in plasma. No difference in trans fatty acid intake is observed between obese and control children, although plasma levels remain higher in obese than in control children after 3 h of a meal. A marked insulin resistance is seen in obese, but it is not correlated with either trans fatty acid intake or plasma concentration.

Sequentially combined estradiol valerate plus levonorgestrel therapy decreases 18:1 trans-fatty acid content of plasma lipids in healthy postmenopausal women

Trans-fatty acids (TFA) have been classified as atherogenic dietary constituents but the effect of hormone replacement therapy (HRT) on their concentrations is not known. We used a washout protocol to study the effect of long-term estrogen and combined estrogen–progestin HRT on plasma elaidate (18:1t), which is the trans isomer of oleate and the major TFA in the diet. The study group comprised 15 women receiving estradiol valerate HRT and 15 women receiving combined HRT with estradiol valerate and levonorgestrel. The concentrations of elaidate in plasma phospholipids, cholesteryl esters and triglycerides were determined by gas chromatography. At baseline, the total plasma elaidate concentration was lower in the combined HRT group than in the estradiol valerate HRT group (p < 0.01). In the combined HRT group, the concentration of elaidate increased significantly after withdrawal of HRT (p < 0.001) and decreased again to the baseline level after restart of therapy (p < 0.001). These changes were due to decreases in the concentrations of phospholipids and triglycerides; in phospholipids there was also a proportional decrease of elaidate. There were no changes in elaidate in women receiving estradiol valerate alone. Our results suggest that long-term combined HRT treatment decreases plasma TFA, which is not achieved by estrogen alone.

Isomeric fatty acids: evaluating status and implications for maternal and child health.

"Isomeric fatty acids" is a term that refers to the trans- and positional isomers formed during hydrogenation of naturally occurring oils. The purposes of this paper are as follows: (i) to summarize potential exposure of infants to isomeric fatty acids by reviewing estimates of isomeric fatty acids in the maternal diet, in human milk, and in infant formula/infant foods, and (ii) to evaluate the evidence for adverse effects of isomeric fatty acids on infant development with respect to growth and essential fatty acid status. Estimates of the intake of trans-fatty acids vary widely both within and across populations. Current estimates of trans-fatty acids in the North American population are 4-11% of total fatty acids or 3-13 g/(person x d), whereas in Mediterranean countries in which olive oil is the primary fat and in Far Eastern countries in which little commercially hydrogenated fat is consumed, per capita consumption of trans-fatty acids is <1-2 g/d. The trans-fatty acid content of human milk reflects the cross-cultural variation in the maternal diet, with trans-fatty acids in human milk samples ranging from 6 to 7% in North America to <0.5% in Hong Kong. Trans-fatty acids are transferred from the maternal diet through the placenta to the developing fetus or through milk to the breast-fed infant. In some studies, plasma trans-fatty acids are inversely related to birth weight and head circumference. The hypothesis that dietary trans-fatty acids could inhibit biosynthesis of long-chain polyunsaturated fatty acids with 20 and 22 carbon atoms and thus affect infant development is supported by studies demonstrating an inverse correlation of plasma trans-fatty acids with n-3 and n-6 longchain polyunsaturated fatty acids in infants. However, no such relationship has been observed in human milk. A definitive answer concerning a potentially adverse effect of dietary trans-fatty acids on infant development awaits future studies.

Infant plasma trans , n−6, and n−3 fatty acids and conjugated linoleic acids are related to maternal plasma fatty acids, length of gestation, and birth weight and length

Arachidonic acid (AA) and docosahexaenoic acid (DHA) are important for growth and neural development. trans Fatty acids (TFAs) may inhibit desaturation of linoleic acid (LA) and alpha-linolenic acid (ALA) to AA and DHA, respectively. Conjugated linoleic acids (CLAs) also alter lipid metabolism and body fat. We determined the associations of birth outcome with maternal and infant plasma concentrations of TFAs, CLAs, AA, and DHA. In healthy women, we sampled maternal blood at 35 wk gestation (n = 58) and umbilical cord blood at birth (n = 70). Mean (+/- SEM) TFA concentrations (% by wt) in infant plasma were as follows: triacylglycerol, 2.83 +/- 0.19 (range: 0.63-12.79); phospholipid, 0.67 +/- 0.03 (0.11-1.33); and cholesteryl ester, 2.04 +/- 0.01 (0.86-4.24). LA, AA, DHA, TFA, and CLA concentrations in infant phospholipids correlated with the same fatty acid in maternal plasma phospholipids (n = 44; P < 0.05). Infant plasma cholesteryl ester and triacylglycerol TFAs and cholesteryl ester CLAs (r = -0.33, -0.42, and -0.49, respectively) were significantly inversely related to length of gestation. Triacylglycerol and cholesteryl ester AA were positively related to length of gestation (r = 0.41 and 0.37, respectively) and birth weight (r = 0.27 and 0.23, respectively). Inverse correlations occurred between infant plasma TFA and DHA concentrations in triacylglycerols (r = -0.33) and between TFA and AA concentrations in cholesteryl esters (r = -0.23). The results suggest possible important effects of TFAs and of AA on fetal growth and length of gestation.

Trans fatty acids and cardiovascular disease risk.

Recent studies continue to confirm previous observations that trans fatty acids elevate low density lipoprotein cholesterol levels, and at relatively high intakes decrease high density lipoprotein cholesterol levels. Considerable interest is focused on the potential benefits of trans-free margarines. Both adipose and plasma trans fatty acid levels reflect dietary intake. Current estimates of trans fatty acid intake in developed countries range from 0.5 to 2.6% of energy, contributed to primarily by differences in food availability and preference, and partly by the methodological differences used to calculate the data.

Study of diet, biomarkers and cancer risk in the United States, China and Costa Rica.

One striking paradox in epidemiologic research is the strong association between diet and cancer in ecologic studies compared with the weaker associations reported in many within-country case-control and cohort studies. However, most ecologic studies have relied on indirect measures of dietary intake, such as food disappearance data. The objectives of our study were to assess the feasibility of collecting dietary and biomarker data from individuals living in countries having markedly different dietary patterns and cultures and to examine the magnitude of the between-country variation in their measurement. Adults surveyed in Shanghai (China), Costa Rica and King County (Washington, USA) completed a 24-hr dietary recall, a cancer risk factor survey, and provided a blood sample. We analyzed a subset of the blood specimens for vitamins C, E, carotenoids and phospholipid fatty acids. We observed substantial differences in nutrient intakes and in mean plasma concentrations of dietary biomarkers across the study populations. For example, King County participants had the highest daily intake of vitamin C (mean 78.3 +/- 12.2 mg compared with 42.6 +/- 38.3 mg in Shanghai and 34.8 +/- 43.8 mg in Costa Rica). The mean plasma vitamin C level in King County was also the highest of the 3 study sites: 927.9 +/- 43.9 microg/dl in King County, 585.7 +/- 35.9 microg/dl in Shanghai and 461.1 +/- 33.1 microg/dl in Costa Rica. Plasma trans fatty acids (a biomarker of a diet high in hydrogenated fats) were highest in King County and lowest in Shanghai.

Study of diet, biomarkers and cancer risk in the United States, China and Costa Rica

One striking paradox in epidemiologic research is the strong association between diet and cancer in ecologic studies compared with the weaker associations reported in many within-country case-control and cohort studies. However, most ecologic studies have relied on indirect measures of dietary intake, such as food disappearance data. The objectives of our study were to assess the feasibility of collecting dietary and biomarker data from individuals living in countries having markedly different dietary patterns and cultures and to examine the magnitude of the between-country variation in their measurement. Adults surveyed in Shanghai (China), Costa Rica and King County (Washington, USA) completed a 24-hr dietary recall, a cancer risk factor survey, and provided a blood sample. We analyzed a subset of the blood specimens for vitamins C, E, carotenoids and phospholipid fatty acids. We observed substantial differences in nutrient intakes and in mean plasma concentrations of dietary biomarkers across the study populations. For example, King County participants had the highest daily intake of vitamin C (mean 78.3 ± 12.2 mg compared with 42.6 ± 38.3 mg in Shanghai and 34.8 ⅔ 43.8 mg in Costa Rica). The mean plasma vitamin C level in King County was also the highest of the 3 study sites: 927.9 ± 43.9 μg/dl in King County, 585.7 ± 35.9 μg/dl in Shanghai and 461.1 ± 33.1 μg/dl in Costa Rica. Plasma trans fatty acids (a biomarker of a diet high in hydrogenated fats) were highest in King County and lowest in Shanghai. Int. J. Cancer 82:28–32, 1999. © 1999 Wiley-Liss, Inc.

Trans-fatty acid patterns in patients with angiographically documented coronary artery disease

The plasma trans-fatty acids of 47 patients with angiographically documented coronary artery disease were compared with those of 56 reference subjects using high-resolution capillary column gas-liquid chromatography to test the hypothesis that trans-fatty acid intake is a risk factor for cardiovascular disease. Individual and total trans-fatty acids were higher in patients than in reference subjects (1.38 vs 1.11% for total trans-fatty acids, p < 0.003; 0.40 vs 0.31% for palmitoleic acid trans, p < 0.001; and 0.28 vs 0.22% for linoleic acid trans, p < 0.007). High-density lipoprotein (HDL) cholesterol and HDL cholesterol/total cholesterol were negatively correlated (r = −0.29, p < 0.004; and r = −0.35, p < 0.001, respectively), whereas triglycerides, total cholesterol and low-density lipoprotein cholesterol were positively correlated (r = 0.47, p < 0.001; r = 0.22, p < 0.03; r = 0.20, p < 0.05, respectively) with palmitoleic acid trans. The correlations were similar and significant for linoleic acid trans, but less strong for total transfatty acids (which is more difficult to measure and has greater variability). Saturated and transfatty acids and total cholesterol are positively associated, whereas HDL/total cholesterol and polyunsaturated fatty acids are negatively associated with coronary artery disease. These results are consistent with the hypothesis that dietary trans-fatty acids are a cardiovascular risk factor.