The Impact of the Essential Fatty Acids (EFA) in Human Health

Linoleic (LA) and α-linolenic acids (ALA) are considered essential fatty acids (EFA) because they are not produced by the human body. This way, EFAs sources must come from the diet. The primary dietary source of n-3 fatty acids is ALA, found in seeds and seed oils. Other important sources are fish oils such as tuna, salmon and herring. Currently, numerous studies suggest possible benefits of essential fatty acids in human health, such as in cardiovascular, cognitive and eye health, and also during pregnancy and childhood. This paper also discusses the impact of fatty acids in human metabolism, and the available evidence regarding its risks. It addresses the relevant debate regarding a general ban of trans fatty acids (TFA) from the world food market, because of the cardiovascular risks associated with its consumption.

Fatty Acids and Triglycerides Composition in Uruguayan Cow, Sheep and Goat Cheeses

Adverse health consequences are associated with consumption of so-called trans fatty acids （FAs） generated during chemical hydrogenation processes. Naturally-occurring trans fats, including trans vaccenic acid （TVA） derived from a conjugated isomer of linoleic acid （18：2 cis-9, trans-11）, （CLA） in contrast, are recognized as having potentially beneficial effects on human health. These natural trans FAs are found in fat from dairy products and meat of ruminants, and have distinct effects compared with trans FAs industrially produced. The lipid composition of cheeses depends on the milk used. In this work was determined CLA and TVA content in milk fat of sheep and cow to be 1.4% and 3.2%, respectively, and from goat, 0.7% and 1.8%. Also, differences in CLA and TVA content were found in fat extracted from samples of the same cheese type made from cow＇s milk from the same company but with different production dates during a year. The levels of CLA and TVA found in Uruguayan cheeses were generally higher than levels reported in previous studies with comparable cheeses produced in other countries. Milk fat is well-known to confer specific properties to foods. This in turn will affect the rheology and sensory attributes as food. For this reason, it is of interest to determine the triglyceride （TAG） composition in milk-derived foods. Results show that there are characteristic differences in the TAG composition of the different cheeses. We found minimal differences between cheeses from goat and sheep but found distinct characteristics for TAGs from cow milk-derived cheese.

Trans Fatty Acid Levels in Foods and Intakes among Population Aged 3 Years and above in Beijing and Guangzhou Cities,China

Objective To understand the dietary intake levels of trans fatty acids （TFA） in a Chinese population and establish a basis for health risk assessment of trans fatty acids. Methods The TFA contents data of 2613 food items and food consumption data of 10,533 people aged 3 years and above in two large cities in China were matched and a simple assessment method was used to estimate the distribution of dietary TFA intake. Results The mean content of TFA was highest in margarine （1.68±0.83 g/100g）, followed by chocolate and candy （0.89±2.68 g/100g）, edible vegetable oils （0.86±0.82 g/100g）, milk （0.83±1.56 g/100g）, and bakery foods （0.41±0.91 g/100g）. TFA intake accounted for 0.34%, 0.30%, 0.32%, and 0.29% of the total energy intake in the 3-6, 7-12, 13-17, and 〉18 year age groups, respectively. Of the populations studied, 0.42% demonstrated TFA intakes （as percentage of energy intake） greater than 1%. The main sources of dietary TFA intake were edible vegetable oils, milk, mutton, and beef, and baked foods, which accounted for 49.8%, 16.56%, 12.21%, and 8.87%, respectively. Conclusion The current intake of TFA among concern regarding the threshold of TFA intake people in two cities did not appear to be of major health as the percentage of total energy recommended by the World Health Organization. Because most TFA were derived from industrially processed foods, the government should reinforce nutrition labeling and regulate food producers to further reduce TFA in food and to provide scientific instruction for consumers to make sound choices.

Mechanisms of Steatosis-Derived Hepatocarcinogenesis:Lessons from HCV Core Gene Transgenic Mice

Hepatitis C virus(HCV)is a major cause of chronic hepatitis,liver cirrhosis,and hepatocellular carcinoma(HCC)worldwide.Among the structural proteins of HCV,the HCV core protein has the ability to regulate gene transcription,lipid metabolism,cell proliferation,apoptosis,and autophagy,all of which are closely related to the development of HCC.Transgenic mice carrying the HCV core gene exhibited age-dependent insulin resistance,hepatic steatosis,and HCC that resembled the clinical characteristics of chronic hepatitis C patients.Several dietary modifications,including calorie restriction and diets rich in saturated fatty acids,trans fatty acids,or cholesterol,were found to influence hepatic steatogenesis and tumorigenesis in HCV core gene transgenic mice.These strategies modulated hepatocellular stress and proliferation,in addition to hepatic fibrotic processes and the microenvironment,thereby corroborating a close interconnection between dietary habits and steatosis-related hepatocarcinogenesis.In this review,we summarize the findings obtained from mouse models transgenic for the HCV genome,with a special focus on HCV core gene transgenic mice,and discuss the mechanisms of steatogenesis and hepatocarcinogenesis induced by the HCV core protein and the impact of dietary habits on steatosis-derived HCC development.

Fatty acid intake in relation to reproductive hormones and testicular volume among young healthy men

Emerging evidence suggests that dietary fats may influence testicular function. However, most of the published literature on this field has used semen quality parameters as the only proxy for testicular function. We examined the association of fat intake with circulating reproductive hormone levels and testicular volume among healthy young Spanish men. This is a cross-sectional study among 209 healthy male volunteers conducted between October 2010 and November 2011 in Murcia Region of Spain. Participants completed questionnaires on lifestyle, diet, and smoking, and each underwent a physical examination, and provided a blood sample. Linear regression was used to examine the association between each fatty acid type and reproductive hormone levels and testicular volumes. Monounsaturated fatty acids intake was inversely associated with serum blood levels of calculated free testosterone, total testosterone, and inhibin B. A positive association was observed between the intake of polyunsaturated fatty acids, particularly of omega-6 polyunsaturated fatty acids, and luteinizing hormone concentrations. In addition, the intake of trans fatty acids was associated with lower total testosterone and calculated free testosterone concentrations （Ptrend = 0.01 and 0.02, respectively）. The intake of omega-3 polyunsaturated fatty acids was positively related to testicular volume while the intake of omega-6 polyunsaturated fatty acids and trans fatty acids was inversely related to testicular volume. These data suggest that fat intake, and particularly intake of omega 3, omega 6, and trans fatty acids, may influence testicular function.

Effect of temperature on milk fats of cow,buffalo,and goat used for frying local food products

Objectives:Thermal processes,such as refining and frying,result in the formation of trans fatty acids(TFAs)in edible oils or fats.Concerning the detrimental effect of TFAs on human health,milk fat samples of cow,buffalo,and goat are collected in order to elucidate TFAs accumulation during thermal processing.Methods:The increased amount of TFAs due to heating is analyzed by attenuated total reflection-Fourier transform infrared(ATR-FTIR)spectroscopy in conjunction with second-derivative treatment and gas chromatographic(GC)analysis.Results:The total amount of TFAs has been increased from 7.71 to 8.25 per cent for cow milk fat,7.12 to 7.82 per cent for buffalo milk fat,and from 6.82 to 7.61 per cent for goat milk fat on heating the samples to 125°C-175°C as predicted by GC.Conclusions:Local food products fried in these milk fats are hence very harmful to human health.These results demonstrate that thermally induced TFAs in milk fats are closely related to the process temperature and time,which should be considered to reduce the formation of TFAs during thermal treatment.