Consumption Of Trans Fatty Acids Research Articles

Expectations for the United Nations high-level meeting on noncommunicable diseases

The United Nations General Assembly’s decision to convene a high-level meeting on the prevention and control of noncommunicable diseases (NCDs) worldwide in September 2011 is a major, timely opportunity to elevate chronic diseases onto the global stage and to encourage action by individual governments.1 Just as the 2001 United Nations General Assembly Special Session on HIV/AIDS was a pivotal moment in the global response to AIDS, there is hope that the September session on NCDs will become an historic rallying point. How shall we judge the success of the meeting? If Member States can address the following five critical elements, then new measurable goals and means of building accountability may be within reach. First, the meeting should put a spotlight on the true scale of morbidity and mortality caused by NCDs and the economic consequences for households, health systems and national economies. It should result in an endorsement of the World Health Organization (WHO) Action plan for the global strategy for the prevention and control of noncommunicable diseases2 and a commitment to a study of their projected economic impact as well as the cost of preventive action. Second, governments should commit to developing national NCD plans by convening, for example, a multisectoral national task force or commission to elaborate country-specific strategies and targets. WHO could support countries in this process. These plans should be required by 2013, with updates on specific targets by 2015 and continuous monitoring by the United Nations. The third key element of success is financing. It is unlikely that there will be new funds pledged at the meeting. In fact, it could be detrimental to focus on raising a specific amount of funding as this might distract governments from other key tasks. Rather than establishing a new institution such as a Global Fund for NCDs or expanding the mandate of the Global Fund to Fight AIDS, Tuberculosis and Malaria, we suggest three feasible financial avenues. These are: (i) seeking joint financing mechanisms such as public–private partnerships;3 (ii) investing in health system reform to deal better with NCDs, e.g. supply of essential drugs and devices, health worker retention, provision of diabetes care through primary providers; and (iii) including NCDs as a line item in government health budgets and donor reporting systems to help monitor budgetary allocations. A fourth requirement is the commitment of governments to strengthening national regulation of NCD risk factors, including pushing for change in the food and beverage industry. This should put into force regulatory frameworks to reduce consumption of trans-fatty acids, salt, alcohol and sugar. Finally, incentives and mechanisms to encourage cross-sectoral action and coordination are central to sustained progress. Finance ministries need to budget sufficient funds; agriculture ministries to reduce subsidies for harmful crops; trade ministries to enlarge access to essential medicines; urban planning and transport ministries to create opportunities for greater physical activity; and education ministries to ensure that school environments provide healthy diets through banning the sale and distribution of harmful foods in schools and promoting health education. Tobacco control efforts could lead discussions in each of these areas given that there have been considerable policy gains. These include the WHO Framework Convention on Tobacco Control and the practical assistance provided to governments through WHO’s MPOWER resources; commitments of more than US$ 500 million from the Bloomberg Family Foundation and the Bill & Melinda Gates Foundation; and increasing attention to the role of tobacco in bilateral trade agreements, in taxation policy and in agriculture. Despite such progress, there is still much work required to curb tobacco use as it is the single most important risk factor for NCDs and kills an estimated 5 million people annually. If the United Nations Secretary-General makes a strong declaration to support the WHO Framework Convention on Tobacco Control in New York this year, this will add significant weight to previous commitments to the Convention made in Geneva. While tobacco use is declining in most wealthy countries, it is increasing in many poor countries of the world, with profound consequences for the future of public health and development. As stock prices for tobacco continue to rise – underscoring the confidence of the markets in tobacco – clear decisions must be made on overcoming barriers to implementation of the WHO Framework Convention on Tobacco Control. These include: investment treaties and associated pressures to open markets; agriculture and loss of employment, and subsidies for harmful crops; difficulties in regulating the private sector; illicit trade in cigarettes and tobacco smuggling; and constraints to implementing tobacco taxation. We hold high expectations for what can be achieved at this high-level meeting, especially if Member States are willing to develop and support a strong outcomes document with agreed set targets and reporting mechanisms to ensure accountability to commitments. This is a crucial first step in stemming the global epidemic in NCDs.

Artificial trans fatty acids in food supply: A global health threat

Purpose: Evidence of adverse health effects of artificial trans fatty acids (TFAs) have accumulated since 1990s, yet TFAs are widely used by several food manufacturers around the world. This review aimed to: ascertain the available evidence of the known unfavourable biochemical properties of artificial TFAs, their metabolic functions and health consequences; estimate their average intake levels and trends in different countries in order to critically evaluate whether more action is required to eliminate them from the diet. Methodology: The published evidence was searched by employing: Medline, Pubmed, InterScience, BioMed Central and Annual Reviews. Findings: With reference to human health, evidences from epidemiological, retrospective and observational studies revealed that the consumption of TFAs could outweigh the health risks posed by saturated fat consumption. The main health concerns included unfavourably altered blood cholesterol concentrations, insulin resistance, foetal brain and neural disturbances, proinflammatory and carcinogenic responses. Great variation exists in the global trends of industrial TFAs intake, being low in Mediterranean region, Japan and Scandinavia and high in parts of United States of America and Iceland. Besides the intense use of TFAs by food manufacturers and in eateries, the use of TFAs in food products is often poorly regulated and ill‐informed to consumers. Value: Since competitive alternatives to TFAs have made them non‐mandatory a broad public health intervention at government level to regulate or completely eliminate them from the national diet is warranted.

Effect of trans fatty acid isomers from ruminant sources on risk factors of cardiovascular disease: Study design and rationale

Substantial evidence clearly demonstrates the deleterious effects of industrially-produced trans fatty acids (TFA); however, data are lacking from large, well controlled human feeding studies that directly compare the effects of industrially-produced and naturally-occurring TFA. The purpose of the current study is to determine whether consumption of TFA derived from different sources differentially affect risk factors of cardiovascular disease (CVD). The study was a randomized, crossover design, controlled-feeding intervention designed to compare the effects of the following diet treatments on risk factors of CVD: low TFA diet (base diet, 34% energy from fat; 0.1% energy from TFA), base diet with vaccenic acid (3.0% energy), base diet with mixed isomers of TFA from partially hydrogenated vegetable oil (3.0% energy), and base diet with cis-9, trans-11 CLA (1.0% energy). The added energy from TFA replaced energy from stearic acid. Participants were required to be between the ages of 25 and 65 years, have a body mass index between 20 and 38 kg/m 2, total cholesterol < 280 mg/dl, fasting triacylglycerol < 300 mg/dl, fasting glucose < 126 mg/dl, and blood pressure < 160/100 mm Hg (controlled with certain medications). Of the 116 participants who were randomized, a total of 95 completed the intervention. Results from this study will be important in determining whether ruminant TFA and industrially produced TFA differentially affect markers of cardiovascular risk, in the context of a highly controlled feeding study.

Consumption of industrial and ruminant trans fatty acids and risk of coronary heart disease: a systematic review and meta-analysis of cohort studies

The aim of this systematic review and meta-analysis was to summarize the evidence from observational studies assessing the association between intake of trans fatty acids (TFA) and the risk of coronary heart disease (CHD), with a specific emphasis on distinguishing between TFA of industrial and ruminant origin. By searching five bibliographic databases, analyses from six published and two unpublished prospective cohort studies, assessing the association of intake of TFA with fatal and/or non-fatal CHD, were identified. Four and three studies reported separate associations for intake of ruminant or industrial-TFA, respectively. The pooled relative risk estimates for comparison of extreme quintiles of total-TFA intake (corresponding to intake increments ranging from 2.8 to ∼10 g/day) were 1.22 (95% confidence interval: 1.08-1.38; P=0.002) for CHD events and 1.24 (1.07-1.43; P=0.003) for fatal CHD. Ruminant-TFA intake (increments ranging from 0.5 to 1.9 g/day) was not significantly associated with risk of CHD (risk ratio (RR)=0.92 (0.76-1.11); P=0.36), and neither was industrial-TFA intake, although there was a trend towards a positive association (RR=1.21 (0.97-1.50); P=0.09). In conclusion, our analysis suggests that industrial-TFA may be positively related to CHD, whereas ruminant-TFA is not, but the limited number of available studies prohibits any firm conclusions concerning whether the source of TFA is important. The null association of ruminant-TFA with CHD risk may be due to lower intake levels.

Ruminant and industrial sources of trans-fat and cardiovascular and diabetic diseases

The various positional isomers of oleic acid (18 : 1Δ9c or 9c-18 : 1) may have distinct biological effects. Detrimental effects of consumption of industrial trans-fatty acids (TFA) (elaidic acid; 18 : 1Δ9t) from partially hydrogenated vegetable oils on CVD risk factors are well documented. In addition, epidemiological data suggest that chronic consumption of industrial sources of TFA could alter insulin sensitivity and predispose for type 2 diabetes. However, intervention studies on this issue have remained inconclusive. Moreover, very little information is available on the effect of natural sources of TFA (vaccenic acid; 18 : 1Δ11t) coming from dairy products and ruminant meat on the development of CVD and type 2 diabetes. The review focuses on the impact of the consumption of ruminant TFA in relation to cardiovascular risk factors, inflammation and type 2 diabetes.

Comparative study between n-6, trans and n-3 fatty acids on repeated amphetamine exposure: A possible factor for the development of mania

In the last decades, foods rich in omega-3 (ω-3) fatty acids (FA) have been replaced by omega-6 (ω-6) and trans FA, which are found in processed foods. The influence of ω-6 (soybean oil – SO), trans (hydrogenated vegetable fat – HVF) and ω-3 (fish oil – FO) fatty acids on locomotor and oxidative stress (OS) parameters were studied in an animal model of mania. Rats orally fed with SO, HVF and FO for 8weeks received daily injections of amphetamine (AMPH — 4mg/kg/mL-ip) for the last week of oral supplementation. HVF induced hyperactivity, increased the protein carbonyl levels in the cortex and decreased the mitochondrial viability in cortex and striatum. AMPH-treatment increased the locomotion and decreased the mitochondrial viability in all groups, but its neurotoxicity was higher in the HVF group. Similarly, AMPH administration increased the protein carbonyl levels in striatum and cortex of HVF-supplemented rats. AMPH reduced the vitamin-C plasmatic levels of SO and HVF-fed rats, whereas no change was observed in the FO group. Our findings suggest that trans fatty acids increased the oxidative damage per se and exacerbated the AMPH-induced effects. The impact of trans fatty acids consumption on neuronal diseases and its consequences in brain functions must be further evaluated.

Trans fatty acids, insulin resistance and diabetes

The possible relationship between consumption of trans fatty acids (TFAs) and risk of insulin resistance or development of diabetes mellitus type II has been considered by a number of human and animal studies over the past decade. This review evaluates the evidence, and concludes that there is limited evidence for a weak association at high TFA intakes, but very little convincing evidence that habitual exposure as part of a standard western diet has a significant contribution to risk of diabetes or insulin resistance. The possibility of increased risk for individuals with particular genotypes (such as the FABP2 Thr54 allele) is of interest, but further work would be required to provide sufficient evidence of any association.

Trans fatty acids and weight gain

Increasing rates of obesity have stimulated research into possible contributing factors, including specific dietary components such as trans fatty acids (TFAs). This review considers the evidence for an association between TFA intake and weight gain. It concludes that there is limited but consistent evidence from epidemiological studies, and from a primate model, that increased TFA consumption may result in a small additional weight gain. Data from a long-term study in a primate model suggest that TFA may have a greater adipogenic effect than cis monounsaturated fatty acids; however, there are currently inadequate mechanistic data to provide a comprehensive and plausible explanation for any such metabolic differences between the types of fatty acids.

Replacing Trans Fat: The Argument for Palm Oil with a Cautionary Note on Interesterification

To replace dietary trans fatty acids (TFA), two practical options exist: revert to a natural saturated fat without cholesterol (most likely palm oil or its fractions) or move to a newer model of modified fat hardened by interesterification (IE). This review summarizes the relative risks for cardiovascular disease inherent in these options. Interestingly, both types of fat have been the subject of nutritional scrutiny for approximately the last 40 years, and both have positive and negative attributes. Only during that period has palm oil production developed to the point where it has become the major edible oil in world markets, making clinical studies of it an important objective. On the other hand, approximately 25 human studies have fed interesterified fat in one form or another over this period, some for weeks, some as a single meal. Two types of diet designs exist. Several fed a small amount of interesterified fat, usually incorporated within a margarine, and stayed below the radar of biological detection of any abnormal metabolism. A few fed interesterified fat that incorporated stearic acid, as interesterified 18:0 (IE-18:0), even comparing it to trans fat and saturated fat, as a major part of total daily calories to assess its metabolic impact per se. These latter 5 to 6 studies clearly reveal negative biological effects on lipoproteins, blood glucose, insulin, immune function, or liver enzymes when relatively high intake of IE-18:0 or palmitic acid (IE-16:0) were fed in fats with sn2–saturated fatty acids. High intake of 18:0 in natural fats can depress total lipoproteins, while IE-18:0 and IE-16:0 at high levels adversely affect lipoprotein metabolism.Still other studies have supplied interesterified fat as a single meal or fed such fat daily only in a single snack, as opposed to incorporating the fat into the entire fat pool consumed at all meals in association with most foods (which is the more physiological approach and more apt to elicit effects). Even in meal studies, IE-18:0 typically delayed fat absorption postprandially, indicating its effect on fat metabolism originating, in part, in the intestine.Mainly 2 saturated fatty acids (18:0 or 16:0) have been interesterified to harden oils, using the 16:0 from fully hydrogenated palm oil or 18:0 from fully hydrogenated soybean oil as the source material. It is not clear that IE-16:0 is as problematic as IE-18:0, but IE-16:0 has been studied less. Levels between 8% energy (%E) and 12%E from 18:0 as interesterified fat (the typical diet provides about 2%E–4%E as 18:0 from natural fats) show the most effect. Detection of adverse effects would seem to start around 7%E–8%E as IE-18:0, but one can assume that effects are initiated, even if undetected, at a lower intake, similar to the situation with TFA. Thus, although an intake of 1%E to 4%E from IE-18:0 does not appear to influence lipoproteins, it is not necessarily the only system affected. The negative effects of IE-18:0 may be alleviated or masked by dilution with other fats, especially by adding 18:2-rich polyunsaturated oils to the diet. This is similar to the trans fat story, i.e., if a limited intake of TFA is heavily diluted with other oils, the consumption of TFA fails to be detected as an adverse effect.Accordingly, more research is warranted to determine the appropriateness of interesterified fat consumption, particularly before it becomes insidiously embedded in the food supply similar to TFA and intake levels are achieved that compromise long-term health.

Lipid profiles and trans fatty acids in serum phospholipids of semi-nomadic Fulani in northern Nigeria.

The Fulani are semi-nomadic pastoralists of West Africa whose diet, culture, and economy are centred on cattle. Previous studies have shown that the Fulani of northern Nigeria derive 50% of their total calories from fat and 30% of their calories from milk, cheese, yogurt, and butter oil that contain significant amounts of trans fatty acids (TFAs), primarily vaccenic acid, which raise total serum cholesterol and low-density lipoproteincholesterol (LDL-C), and lower high-density lipoprotein-cholesterol (HDL-C). The study was conducted to know how the consumption of relatively large amounts of dairy products by adult Fulani affected the TFA content of their serum phospholipids. Blood samples were collected from 22 male and 29 female Fulani, aged 35-60 years, who were living in rural areas of Gombe state in northeastern Nigeria. The total serum phospholipid fraction was isolated, and its fatty acid composition was determined. Surprisingly, vaccenic acid was not detected, and three other TFAs--18:1-t6, 18:1-t9, and 18:2-t9,t12--together accounted for only 0.16% of the total fatty acid. The mean serum total cholesterol, LDL-C, and triglyceride concentrations of the subjects were within the normal range for populations in developed countries; however, at 32 mg/dL, the mean serum HDL-C concentration of the Fulani males was slightly below the lower limit of the reference range. No correlations were observed between the total TFA percentage or that of the three individual TFAs and any of the parameters of the serum lipid profile. These findings indicate that, with respect to TFAs at least, the fatty acid pattern of the serum phospholipids of Fulani pastoralists does not reflect the high TFA content of their traditional diet. Despite the consumption of rumenic acid-rich dairy products, for unknown reasons, the semi-nomadic Fulani manage to maintain a low level of TFAs in their blood and a relatively healthful serum lipid profile. While the mechanism that accounts for this disconnect between the consumption of TFAs by Fulani pastoralists and the proportion of TFAs in their serum phospholipids is obscure, possibilities include discrimination against rumenic acid during the process of triglyceride synthesis and chylomicron synthesis in the intestine and the preferential oxidation of TFAs by Fulani the people compared to other ethnic groups.

Possible involvement and the mechanisms of excess trans-fatty acid consumption in severe NAFLD in mice

Excessive trans-fatty acids (TFA) consumption has been thought to be a risk factor mainly for coronary artery diseases while less attention has been paid to liver disease. We aimed to clarify the impact of TFA-rich oil consumption on the hepatic pathophysiology compared to natural oil. Mice were fed either a low-fat (LF) or high-fat (HF) diet made of either natural oil as control (LF-C or HF-C) or partially hydrogenated oil, TFA-rich oil (LF-T or HF-T) for 24 weeks. We evaluated the liver and body weight, serological features, liver lipid content and composition, liver histology and hepatic lipid metabolism-related gene expression profile. In addition, primary cultures of mice Kupffer cells (KCs) were evaluated for cytokine secretion and phagocytotic ability after incubation in cis- or trans-fatty acid-containing medium. The HF-T-fed mice showed significant increases of the liver and body weights, plasma alanine-aminotransferase, free fatty acid and hepatic triglyceride content compared to the HF-C group, whereas the LF-T group did not differ from the LF-C group. HF-T-fed mice developed severe steatosis, along with increased lipogenic gene expression and hepatic TFA accumulation. KCs showed increased tumor necrosis factor secretion and attenuated phagocytotic ability in the TFA-containing medium compared to its cis-isomer. Excessive consumption of the TFA-rich oil up-regulated the lipogenic gene expression along with marked hepatic lipid accumulation. TFA might be pathogenic through causing severe steatosis and modulating the function of KCs. The quantity and composition of dietary lipids could be responsible for the pathogenesis of non-alcoholic steatohepatitis.

Food sources of individual plasma phospholipid trans fatty acid isomers: the Cardiovascular Health Study

The overall consumption of trans fatty acids (TFAs) increases the risk of coronary artery disease. However, multiple TFA isomers exist, each with potentially different health effects. Different food sources of these specific TFA isomers are not well established. Our objective was to determine the major independent food sources of specific TFA isomers. We investigated relations of major potential food sources of TFAs, as assessed by serial food-frequency questionnaires, with 10 plasma phospholipid TFA isomers [5 trans (t-) 18:1, 3 t-18:2, and 2 t-16:1] in 3330 older adults in the Cardiovascular Health Study, a community-based multicenter cohort. Stepwise regression was used to identify independent major food sources of individual plasma phospholipid TFA isomers, which were adjusted for demographic, lifestyle, and dietary factors. All 5 t-18:1 isomers were similarly associated with foods commonly made with partially hydrogenated vegetable oils (PHVOs), including biscuits (0.51 higher SD of total 18:1 fatty acid concentrations per serving/d, P < 0.01), chips and/or popcorn (0.33 higher SD per serving/d, P = 0.02), margarine (0.32 higher SD per serving/d, P < 0.001), fried foods (0.32 higher SD per serving/d, P = 0.04), and bakery foods (0.23 higher SD per serving/d, P = 0.02). Each of the t-18:2 isomers were associated only with bakery foods (0.50 higher SD of total 18:2 fatty acid concentrations per serving/d, P < 0.001). Ruminant foods were major correlates of t-16:1n-7, including red meats (0.72 higher SD per serving/d, P < 0.001), butter (0.43 higher SD per serving/d, P < 0.001), and higher-fat dairy (0.37 higher SD per serving/d, P < 0.001). In contrast, t-16:1n-9 were derived mainly from margarine (0.31 higher SD per serving/d, P < 0.001). t-18:1 Isomers are similarly derived from multiple PHVO-containing foods. In contrast, t-18:2 and t-16:1n-9 isomers are derived from more-specific types of PHVO-containing foods. Ruminant foods are major sources of t-16:1n-7. Different TFA isomers and dietary sources should be considered when investigating health effects and interventions to lower TFAs.

Trans Fat Bans and Human Freedom

A growing body of evidence has linked consumption of trans fatty acids to cardiovascular disease. To promote public health, numerous state and local governments in the United States have banned the use of artificial trans fats in restaurant foods, and additional bans may follow. Although these policies may have a positive impact on human health, they open the door to excessive government control over food, which could restrict dietary choices, interfere with cultural, ethnic, and religious traditions, and exacerbate socioeconomic inequalities. These slippery slope concerns cannot be dismissed as far-fetched, because the social and political pressures are place to induce additional food regulations. To protect human freedom and other values, policies that significantly restrict food choices, such as bans on types of food, should be adopted only when they are supported by substantial scientific evidence, and when policies that impose fewer restrictions on freedom, such as educational campaigns and product labeling, are likely to be ineffective.

Trans Fatty acid consumption, lifestyle and type 2 diabetes prevalence in a Spanish population

To analyse the association of trans fatty acid (TFA) consumption with the risk of type 2 diabetes and lifestyle in a South European population. Data were obtained from two population-based cross-sectional surveys conducted in Gerona (Spain) in 2000 and 2005. The present analysis included 7,774 free-living Spanish men and women aged 35-74 years. Diet was assessed by a validated food frequency questionnaire. Fasting blood sugar was measured and history of diabetes recorded. trans Fatty acid intake was relatively low in our study population (1.5 g d(-1) for women and 1.8 g d(-1) for men). Multiple logistic regression analysis revealed a null association between TFA intake and risk of type 2 diabetes in men and women. Total energy intake, alcohol consumption and the prevalence of smoking increased across quartiles of TFA intake. An inverse association was found between TFA intake and the consumption of vegetables, fruit, fish, legumes, white bread and olive oil in both genders (p < 0.001) after adjusting for energy intake. In contrast, intakes of meat, sausages and pastry products increased across quartiles of TFA intake in both genders (p < 0.001). trans Fatty acid intake was not associated with a higher risk of type 2 diabetes. Higher TFA intake was associated with less healthy lifestyle and dietary habits in both sexes.

Trans-Fatty acid consumption and its association with distal colorectal cancer in the North Carolina Colon Cancer Study II

trans-Fatty acid consumption and its association with distal colorectal cancer in the North Carolina Colon Cancer Study II

Trans-fatty acids and nonlipid risk factors

Consumption of industrially produced trans-fatty acids (TFA) is associated with substantial risk of coronary heart disease (CHD). The magnitude of this relationship, as well as emerging associations with end points such as diabetes and sudden cardiac death, cannot be fully explained by the well-established adverse effects of TFA on serum lipids. We review the evidence for effects of TFA intake on nonlipid risk factors. Based on evidence from randomized controlled trials, observational studies, animal experiments, and in vitro studies, these include effects on systemic inflammation, endothelial dysfunction, visceral adiposity, insulin resistance, and arrhythmic risk. The types and strength of evidence for each of these nonlipid effects varies, but the overall constellation of findings is qualitatively and quantitatively unique among dietary fats. The multiple adverse effects and implicated pathways are consistent with the observed strong associations of TFA consumption with CHD risk. These nonlipid effects also explain why TFA consumption may adversely impact other non-CHD diseases and end points.

Trans-Fatty acid consumption and its association with distal colorectal cancer in the North Carolina Colon Cancer Study II

Recently, the potential health effects of trans-fatty acid consumption have raised concerns. A few studies have examined the risk of colorectal cancer with increasing consumption of trans-fatty acids, but none investigated the risk of rectal cancer, which may have different risk factors than colon cancer. Our objective was to explore the relationship between trans-fatty acid consumption and distal colorectal (sigmoid, rectosigmoid, and rectal) cancer using a case-control study of Whites (n = 1,516) and African Americans (n = 392) in North Carolina from 2001 to 2006. Matched cases and controls were interviewed about demographic information, lifestyle factors, and diet. White cases reported higher mean consumption of trans-fatty acid than White controls, but mean consumption was similar for African American cases and controls. Relative to the lowest quartile, the highest quartiles of energy-adjusted trans-fatty acid consumption were positively associated with distal colorectal cancer for Whites [adjusted ORs for the third and fourth quartiles are 1.54 (95%CI: 1.12, 2.13) and 1.45 (95%CI: 1.04, 2.03), respectively]. Consumption was not associated with distal colorectal cancer in African Americans [adjusted ORs for the third and fourth quartiles are 0.98 (95%CI: 0.47, 2.05) and 0.87 (95%CI 0.42, 1.81), respectively]. In conclusion, high consumption of trans-fatty acids was positively associated with distal colorectal cancer among Whites.

Dietary intake of trans fatty acids as a cardiovascular risk factor in a population of Italian teenagers

Trans fatty acids are unsaturated fatty acids produced by the partial hydrogenation of polyunsaturated oils. Over the last few years, an increasing interest on these fatty acids has been shown because of their role in the pathogenesis of cardiovascular diseases. To date, major scientific associations strongly recommend consuming a low intake of trans fatty acids for the prevention of cardiovascular diseases, but data on the consumption of these fatty acids in the general population are still lacking. We conducted this observational study on a population of Italian teenagers in order to evaluate the consumption of trans fatty acids in the diet. We studied 81 Italian teenagers, 45 males and 36 females, with a median age of 16 years. To assess their consumption of trans fatty acids, we used the "High School Survey", a questionnaire prepared by the Harvard Medical School. Total calories of the studied population were 2359.2 +/- 591.5 kcal/day with a mean intake of trans fatty acids of 3.24 +/- 1.48 g/day, corresponding to 1.23% of the total energy. A relevant proportion of subjects, namely 51 (62.9%), exceeded the limit contribution of 1% of energy from trans fatty acids. Their intake of total calories and trans fatty acids significantly increased according to their increasing age (p = 0.0003 for trend). Our data, therefore, obtained in a limited population of Italian adolescents, showed that a consistent proportion of adolescents does not follow the nutritional recommendations for intake of trans fatty acids, likely increasing their risk of cardiovascular diseases.

Consumption and Health Effects of Trans Fatty Acids: A Review

Consumption of industrially produced trans fatty acids (TFA) remains high in many populations, particularly in developing nations where partially hydrogenated vegetable oils are frequently used for home cooking and among individuals in developed countries having high intakes of bakery or processed foods. Well-controlled observational studies and randomized trials indicate that TFA consumption adversely affects multiple risk factors for chronic diseases, including numerous blood lipids and lipoproteins, systemic inflammation, endothelial dysfunction, and possibly insulin resistance, diabetes, and adiposity. Growing evidence for the latter effects is particularly concerning given the worldwide obesity pandemic and high contents of industrially produced TFA in many foods marketed toward children. Consistent evidence from prospective observational studies of habitual TFA consumption and retrospective observational studies using TFA biomarkers indicates that TFA consumption increases risk of clinical coronary heart disease (CHD). Based on the adverse effects of risk factors and consistent relationships with clinical endpoints, the evidence that TFA consumption increases CHD risk is convincing. Some evidence suggests that TFA consumption may also increase other disease outcomes, but further investigation is needed to confirm the presence and magnitude of such effects. More research is also needed to understand how specific TFA isomers of varying chain length and double bond location may affect different biologic pathways of disease. Both individual- and policy-level initiatives to decrease TFA consumption should continue, particularly in population subgroups and in developing nations with high consumption of partially hydrogenated vegetable oils.

Acides gras trans: effets sur le métabolisme des lipoprotéines et le risque cardiovasculaire

Dietary trans fatty acids (TFA) (mainly 18:1 isomers) have two sources: they are formed during the natural bacterial hydrogenation of unsaturated fatty acids in ruminants or they come from the industrial hydrogenation of unsaturated vegetable oils. Total trans fatty acids account for 1.3% of total energy intake in France compared to 2-3% in USA. Recent epidemiologic studies and meta-analyses of well-designed controlled trials clearly showed that trans fatty acids are associated with an increase of cardiovascular risk. It seems that TFA from industrial sources are responsible for the deleterious effects particularly on lipoprotein metabolism. Specifically the consumption of industrial TFA has been associated with high plasma concentrations of triacylglycerols, LDL-cholesterol and small dense LDL and lower HDL-cholesterol concentrations. The very recent interventional trials allowed for a comparison of TFAs from different sources suggest that the intake of natural TFA have no or neutral effects on plasma lipids and other cardiovascular risk factors. However, the mechanisms underlying the isomer-specific effects are not well understood and warrant further investigations.