Acyl pattern of adipose tissue triglycerides, plasma free fatty acids, and diet of a group of men participating in a primary coronary prevention program (the Oslo Study)

The acyl pattern of adipose tissue triglycerides and of plasma free fatty acids were determined after 7 yr of diet intervention on elevated plasma cholesterol in 42 men taking part in the smoking-lipid trial of the Oslo Study. Twenty-two of the men were advised to change dietary habits (mainly reduce saturated fat) whereas the remaining 20 were controls. The adipose tissue from men in the intervention group contained relatively more linoleic and linolenic acids and relatively less saturated and monounsaturated fatty acids compared to men in the control group. There were strong correlations between the relative content of several fatty acids in adipose tissue triglycerides and plasma free fatty acid. Furthermore, there was a close correlation between the intake of polyunsaturated fatty acids found in a dietary survey done 2 to 3 yr before this study and the relative content of polyunsaturated fatty acids in adipose tissue.     

Long-chain n-3-to-n-6 polyunsaturated fatty acid ratios in breast adipose tissue from women with and without breast cancer

Animal studies suggest that dietary polyunsaturated fatty acids (PUFAs) of the n-6 class, found in corn and safflower oils, may be precursors of intermediates involved in the development of mammary tumors, whereas long-chain (LC) n-3 PUFAs, found in fish oil, can inhibit these effects. This case-control study was designed to examine the relationship between the PUFA composition of breast adipose tissue and the risk of breast cancer. Using fatty acid levels in breast adipose tissue as a biomarker of past qualitative dietary intake of fatty acids, we examined the hypothesis that breast cancer risk is negatively associated with specific LC n-3 PUFAs (eicosapentaenoic acid and docosahexaenoic acid) and positively associated with n-6 PUFAs (linoleic acid and arachidonic acid). Breast adipose tissue was collected from 73 breast cancer patients and 74 controls with macromastia. The fatty acid levels were determined by gas-liquid chromatography. A logistic regression model was used to obtain odds ratio estimates while adjusting for age. The age-adjusted n-6 PUFA (linoleic acid and arachidonic acid) content was significantly higher in cases than in controls (P = 0.02). There was a trend in the age-adjusted data suggesting that, at a given level of n-6 PUFA, LC n-3 PUFAs (eicosapentaenoic acid and docosahexaenoic acid) may have a protective effect (P = 0.06). A similar inverse relationship was observed with LC n-3-to-n-6 ratio when the data were adjusted for age (P = 0.09). We conclude that total n-6 PUFAs may be contributing to the high risk of breast cancer in the United States and that LC n-3 PUFAs, derived from fish oils, may have a protective effect.     

Site-specific differences in the fatty acid composition of abdominal adipose tissue in an obese population from a Mediterranean area: relation with dietary fatty acids, plasma lipid profile, serum insulin, and central obesity.

BACKGROUND: Abdominal obesity is associated with coronary risk, although causality is not well established. OBJECTIVE: In an obese Mediterranean population, we measured the fatty acid composition of adipose tissue, its relation with dietary fatty acids and central fat deposition, and its influence on plasma lipids and insulin. DESIGN: Adipose tissue samples were obtained from 84 obese patients (29 men, 55 women) aged 30-70 y (body mass index, in kg/m(2): 27-35). We measured concentrations of insulin and lipids in plasma and fatty acids in subcutaneous, omental, and perivisceral fat. Dietary fatty acid intake was assessed with a 7-d diet record. RESULTS: The population studied was normolipidemic and normoinsulinemic. There were important differences in fatty acid composition between tissue sites: saturated fatty acids were higher and monounsaturated fatty acids were lower in perivisceral than in subcutaneous fat (P < 0.05). Significant correlations were found for oleic, linoleic, alpha-linolenic, and total n-6 polyunsaturated fatty acids between the subject's habitual diet and adipose tissue composition. Oleic and n-3 fatty acids from adipose regions were negatively correlated with apolipoprotein B and triacylglycerols; adipose tissue 22:1n-9, 20:2n-6, stearic acid, and eicosapentaenoic acid were positively correlated with HDL and apolipoprotein A; and adipose tissue myristic acid was negatively correlated with apolipoprotein A (P < 0.05). Central obesity was positively associated with n-6 polyunsaturated fatty acids and inversely associated with monounsaturated fatty acids and n-3 polyunsaturated fatty acids in adipose tissue (P < 0.05). CONCLUSION: The differences found in the composition and metabolism of perivisceral, omental, and subcutaneous fats may indicate that their atherogenic capacities also differ.     

Relationship of diet to the fatty acid composition of human adipose tissue structural and stored lipids

The habitual intake of 20 healthy free-living subjects was determined by two 7-day food records. Documented fatty acid intakes were utilized to examine the influence of fatty acid intake on fatty acid composition of stored and structural lipids in subcutaneous adipose tissue. Subjects with higher intakes of saturated fatty acids exhibited increased levels of total saturated fatty acids and decreased polyunsaturated fatty acids in adipose tissue triglycerides (p less than 0.01). The dietary P/S ratio was significantly related to the saturated and polyunsaturated content of stored lipids. In the phospholipid fraction, relationships were found between dietary C18:2(6) and the P/S ratio of phosphatidylcholine (p less than 0.05). The essential fatty acid content of the two phospholipids studied was related to the dietary fats consumed. Relationships were identified between major fatty acids in the triglyceride and phospholipid fraction. Although diet was found to relate to fatty acid composition, the structural lipids in human adipose tissue appear more resistant to compositional change than stored triglycerides.     

Adipose Fat Quality vs Quantity: Relationships with Children''s Serum Lipid Levels

BACKGROUND: There is a controversy as to the relative importance of obesity vs quality of dietary fat in the prediction of serum lipoproteins in children. A reason for this is an apparent lack of studies implementing biomarkers of long-term dietary fat intake among children. The objective of the present study was to assess the relative contribution of degree of obesity, fat centrality, and quality of adipose tissue fat in the prediction of serum lipids in 12-year-old children. METHODS: Pupils came from 40 schools randomly selected among 541 primary schools in three different provinces of the island of Crete. One thousand forty-six pupils were examined at age 6. At age 9, a representative sample from the original cohort (n = 579) was randomly selected for reevaluation. At the age of 12, a representative sample of 831 pupils was reexamined. At ages 6, 9, and 12, serum lipid measures were obtained from 941, 458, and 791 children, respectively. At age 12, data were obtained on pupils' anthropometry, serum lipids, dietary intake, physical fitness, and physical activity. Adipose tissue fatty acid data were obtained from a subsample of 194 children at age 12. RESULTS: Regression analyses indicated that children's serum triglycerides related positively to body mass index and waist-hip ratio (WHR). Serum HDL-C related negatively to WHR and positively to endurance run test, an index of physical fitness. Dietary fatty acids, assessed by a single administration of 3-day weighed-food records, did not relate to serum lipids. However, serum HDL-C related negatively to sum of adipose polyunsaturated fatty acids, a measure of long-term polyunsaturated fat intake. CONCLUSIONS: It appears that obesity and fat centrality are stronger predictors of children's serum lipids than the quality of long-term dietary fat intake or adipose tissue fatty acid composition. It is possible that this finding may relate to the particular subcutaneous depot studied. It is suggested that future studies study abdominal rather than buttock adipose tissue fatty acid composition in relation to children's serum lipid levels.     

Comparison between habitual intake of polyunsaturated fatty acids and their concentrations in serum lipid fractions

To evaluate the validity of the cross-check dietary history method for the assessment of the habitual intake of polyunsaturated fatty acids, the relationship was investigated between the estimated intake of these fatty acids and their relative amounts in the various serum lipid fractions. Food intake data were obtained from a group of volunteers participating in a long-term epidemiological study in the Dutch town of Zutphen. The fatty acid composition of total lipids, phospholipids, triglycerides and cholesterol esters was determined in fasting serum samples from these volunteers. Although correlations between the calculated dietary intake of timnodonic acid (20:5(n-3), TA) and cervonic acid (22:6(n-3), CA), on the one hand, and the relative amounts of these fatty acids in the various serum lipid fractions, on the other, appeared to be statistically significant, no more than about 20 per cent of the variance in the serum values could be explained on the basis of dietary intake. For linoleic acid (18:2(n-6), LA) this was 55 per cent. It is concluded that the cross-check dietary history method is an acceptable technique for estimating the habitual intake of linoleic acid of a given individual. For the fish-related fatty acids, however, this method is less reliable. This discrepancy most probably results from the large differences in TA and CA contents in the same foods. In addition, a negative association with the calculated LA intake on the proportional amount of TA for most of the serum lipid fractions was demonstrated. This indicates an interference of dietary LA on the metabolism of TA.     

Adipose tissue n-6 fatty acids and acute myocardial infarction in a population consuming a diet high in polyunsaturated fatty acids

BACKGROUND: The Jewish population of Israel consumes a diet rich in n-6 polyunsaturated fatty acids (PUFAs), principally linoleic acid. The consequences of this diet for ischemic heart disease (IHD) remain unclear. OBJECTIVE: We assessed the association of adipose tissue n-6 fatty acids, which are derived entirely from the diet, with acute myocardial infarction (AMI). DESIGN: A total of 180 cases and 492 IHD-free controls aged 25-64 were included in a population-based case-control study of Jerusalem residents hospitalized with a first AMI. Diet was assessed by the use of a food-frequency questionnaire and adipose tissue fatty acids by gas chromatography of biopsy samples taken from subcutaneous gluteal tissue. The data were analyzed by multivariate logistic regression. RESULTS: Dietary PUFAs (: 10.1% of energy) correlated (r = 0.43, P < 0.001) with adipose tissue linoleic acid, which constituted 25.6% of storage fatty acids. High intakes of linoleic acid were not associated with excess risk of AMI (age- and sex-adjusted odds ratio for the third versus the first tertile: 0.96; 95% CI: 0.62, 1.48; NS). In contrast, arachidonic acid, the long chain n-6 derivative of linoleic acid, was positively associated with AMI (age- and sex-adjusted odds ratio: 2.12; 95% CI: 1.33, 3.36; P = 0.004). With multivariate adjustment, there was no evidence for an adverse association of linoleic acid with AMI, whereas the risk associated with arachidonic acid persisted, albeit attenuated. CONCLUSIONS: A very high linoleic acid intake does not appear to confer increased risk of nonfatal AMI. Nonetheless, the increased risk associated with arachidonic acid, a finding that requires confirmation, tempers an inference that diets rich in n-6 fatty acids are safe vis-à-vis coronary health.     

Assessment of individual fatty acid intake

Dietary assessment of individual fatty acid intake is difficult due to a number of limitations. Information regarding the type, quantity and brand-name of fat used in cooking and at the table is required. In addition, margarine manufacturers may change the component oils used for reasons of cost, which changes the fatty acid composition of their products from season-to-season. Independent markers of fatty acid intake are required, therefore, to compensate for these limitations. Adipose tissue concentrations have been used as a measure of habitual intake of fatty acid groups and individual fatty acids in numerous studies. Saturated (SFA) and monounsaturated fatty acids (MUFA) are generally poorly correlated with adipose tissue concentrations, which can be explained partly by endogenous synthesis. In general, adipose tissue concentrations of exogenously-produced fatty acids (n-3 and n-6 polyunsaturated fatty acids (PUFA)) are well correlated with estimates of habitual intake. Correlations between dietary trans unsaturated fatty acids (TUFA) and adipose tissue concentrations vary between countries, which may be due to differences in dietary sources. Correlations may be affected by differences in bioavailability or selective retention of fatty acids in certain tissue lipids.     

Type A behavior and adipose tissue linoleic acid: implications for stress management.

The purpose of the present study was to investigate the relation between Type A behavior and adipose tissue linoleic acid composition.

The sample consisted of 73 male and female Cretan adults, 23-64 years of age. Anthropometric and arterial blood pressure measurements were taken. Adipose tissue samples were collected by aspiration and data concerning general health habits were obtained. Food intake was estimated by a 24-hour dietary recall, while Type A profile was assessed with a Greek translation of the Bortner scale.

Factors associated with Type A profile are adipose tissue linoleic acid (p < 0.0004), annual income (p < 0.001), total serum cholesterol (p < 0.009), and adipose fat myristoleic acid (p < 0.02). Negative correlations were observed between adipose linoleic and myristoleic acids and the dependent variable.

It appears that adipose tissue linoleic acid may be one of the etiological factors for Type A behavior in adults.     

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.     

Validity of the fatty acid composition of subcutaneous fat tissue microbiopsies as an estimate of the long-term average fatty acid composition of the diet of separate individuals

The relationship between the fatty acid composition of subcutaneous adipose tissue and diet was estimated in 59 Dutch women aged 32-35 years. Food consumption was estimated by taking the means of nineteen 24-hour recalls administered over a period of two and a half years, August 1981-December 1983. Highly significant correlations were found between linoleic acid content of fat tissue and diet (r = 0.70) and also between the linoleic acid-to-saturated fatty acid (linoleic/S) ratio of fat tissue and diet (r = 0.62). This confirms the hypothesis that on an individual level the fatty acid composition of the adipose tissue is a valid index for the habitual dietary fatty acid composition of free-living adults. When using one 24-hour recall instead of the average of 19 recalls, the correlation coefficient between the linoleic/S ratio of the diet and that of the adipose tissue was substantially decreased. This demonstrates the weakening effect of the large day-to-day variation in within-person intake on the correlation between a short-term assessment of the nutrient intake of an individual and a biochemical indicator of long-term nutritional status.     

Adipose tissue fatty acids and risk of myocardial infarction--a case-control study

OBJECTIVES: To study the association between content in adipose tissue of very long-chain n-3 fatty acids, trans fatty acids, linoleic acid and alpha-linolenic acid and risk of a first myocardial infarction. DESIGN AND SUBJECTS: A case-control design among 100 patients and 98 population controls both men and postmenopausal women, age 45-75 y. Adipose tissue fatty acids were determined by gas-liquid chromatography. Intake data were obtained through interview using a validated food frequency questionnaire. RESULTS: Dietary intake and adipose tissue content of the fatty acids studied correlated significantly. Adipose tissue contents of eicosapentaenoic acid (20:5n-3), docosapentaenoic acid (22:5n-3) and docosahexaenoic acid (22:6n-3) were significantly lower while those of trans fatty acids, linoleic and alpha-linolenic acid were significantly higher in patients than in controls. Age and sex adjusted odds ratios (OR) were significantly reduced with increasing quintiles of very long-chain n-3 fatty acids, thus the OR in the fifth compared to the first quintile was 0.23 (95% CI 0.08-0.70). After further adjustment for waist-to-hip ratio, smoking, family history of CHD and content of trans fatty acids, the OR in the highest quintile was 0.17 (95% CI 0.04-0.76) and the P for trend 0. 016. Age and sex adjusted OR was increased in the fifth compared to the first quintile of trans fatty acids (OR 2.81, 95% CI 1.16-6.84), linoleic acid (OR 2.10, 95% CI 0.87-5.07) and alpha-linolenic acid (OR 1.96, 95% CI 0.83-4.61), and P for trend was 0.002, 0.005 and 0. 020, respectively. The trends remained significant after adjustment for waist-to-hip ratio, smoking, and family history of coronary heart disease. Trans fatty acids, linoleic acid and alpha-linolenic acid in adipose tissue were strongly correlated, indicating a common source, most likely margarine. When each of these fatty acid species were adjusted for the two others the trends were no longer significant. CONCLUSION: Intake of very long-chain n-3 fatty acids as reflected in adipose tissue content is inversely associated with risk of myocardial infarction. Trans fatty acids, linoleic and alpha-linolenic acid were intercorrelated and associated with increased risk. It is suggested that the increased risk may be connected to trans fatty acids or to some other factor associated with margarine consumption. European Journal of Clinical Nutrition 54, 618-625.     

Evaluation of a food frequency questionnaire with weighed records, fatty acids, and alpha-tocopherol in adipose tissue and serum.

The authors examined the validity of a self-administered 180-item food frequency questionnaire in 125 Norwegian men aged 20-55 years who filled in the questionnaire and completed 14-day weighed records in fall 1995 to winter 1995/6. Spearman correlation coefficients between the two measurements ranged from 0.42 for percent of energy from fat to 0.66 for sugar intake (median r = 0.51). On average, 39% of the men were classified in the same quartile with the two methods, and 3% in the opposite quartile. Correlation coefficients between intake of fatty acids estimated from the questionnaire and the relative amounts of fatty acids in adipose tissue were: linoleic acid (18:2, n-6), r = 0.38; alpha-linolenic acid (18:3, n-3), r = 0.42; eicosapentaenoic acid (20:5, n-3), r = 0.52; and docosahexaenoic acid (22:6, n-3), r = 0.49. The correlations for these fatty acids between the total serum lipids and the diet were 0.16, 0.28, 0.51 and 0.52, respectively. The data suggest that very-long-chain n-3 fatty acids in adipose tissue and total serum lipids reflect the dietary intake of very-long-chain n-3 fatty acids to the same degree. No associations were observed between intake of alpha-tocopherol and concentration in adipose tissue and serum.     

Tocopherols and polyunsaturated fatty acids in human tissues.

Five tissues from three adults who died suddenly and three adult cancer victims were analyzed for alpha- and gamma-tocopherols and fatty acids. When compared with two reports in 1949 and 1958, the three presumably normal subjects had alpha-tocopherol concentrations in liver, muscle and adipose tissue in about the same range as earlier, but heart was twice as high and lung was three times higher than earlier. The content of gamma-tocopherol in all tissues was considerably higher than in 1949 or 1958. Tissues from cancer patients were no lower in alpha-tocopherol than tissues from normal subjects. Adipose tissue from three of the six subjects contained linoleic acid exceeding 15 per cent of total fatty acids. Tocopherols in these subjects, expressed on a tissue weight or tissue lipid basis, were not remarkable. The molar ratio of polyunsaturated fatty acids to alpha-tocopherol in heart and lung was calculated and its possible use in evaluating vitamin E status is discussed.     

Dietary intake of fatty acids and serum C-reactive protein in Japanese

BACKGROUND: Inflammation has been established as a risk factor for cardiovascular diseases. The relationships of polyunsaturated fatty acids (PUFAs) and monounsaturated fatty acids to inflammation are still controversial in Western populations. The relationships are not clear in Japanese whose intake of seafood-based long-chain n-3 PUFAs is high. METHODS: We conducted a cross-sectional epidemiologic study in the Japanese population (1,556 men and 1,461 women aged 35-60). Serum high sensitivity C-reactive protein (CRP) was measured, and intakes of 7 specific fatty acids (% of energy) were evaluated by a validated self-administered dietary history questionnaire. RESULTS: CRP was significantly and inversely related to the intakes of oleic acid (p=0.008) and alpha-linolenic acid (p=0.026) in women after adjustment for confounding factors. A multiple regression analysis showed that, especially in the middle tertile of long-chain n-3 PUFAs (eicosapentaenoic acid and docosahexaenoic acid) intake, CRP was inversely related to the intake of oleic acid and linoleic acid in both sexes and to the intake of alpha-linolenic acid in women. CONCLUSION: Intakes of oleic acid, linoleic acid, and alpha-linolenic acid would reduce serum CRP, especially when the intake of long-chain n-3 PUFAs is at a moderate level in Japanese.     

Polyunsaturated fatty acid intake is adversely related to liver function in HIV-infected subjects: the THUSA study

BACKGROUND: Dietary fat intake in the South African population is increasing. This population also has a high prevalence of HIV infection. However, information about metabolic effects of dietary fatty acids on HIV-infected subjects is lacking. OBJECTIVE: Our objective was to investigate the relation between dietary fatty acid intake and liver function in HIV-infected compared with HIV-uninfected subjects. DESIGN: This cross-sectional epidemiologic survey included a representative sample of 1854 apparently healthy black volunteers aged > or =15 y, who were recruited from 37 randomly selected sites throughout the North West province of South Africa. Data from 216 asymptomatic HIV-infected and 1604 HIV-uninfected subjects were used. RESULTS: Intakes of polyunsaturated fatty acids (PUFAs), linoleic acid (n-6), and the ratio of PUFAs to saturated fatty acids (SFAs) were positively associated with all the liver enzymes measured in HIV-infected subjects (R = 0.16-0.65). Most of these R values differed significantly from the R values for HIV-uninfected subjects. No associations were seen between liver enzymes and intakes of SFAs and monounsaturated fatty acids. Vitamin E intake was positively associated with serum gamma-glutamyl transpeptidase (R = 0.23), alanine aminotransferase (R = 0.37), and aspartate aminotransferase (R = 0.58) in HIV-infected subjects; these correlations differed significantly from those of the HIV-uninfected subjects because PUFA sources are the main carriers of vitamin E. CONCLUSIONS: The results suggest that n-6 PUFA intakes may be related to liver damage in these HIV-infected asymptomatic subjects. The reasons or mechanisms responsible are not clear, and further research is necessary to determine the optimal safe amounts for intake of n-6 PUFAs by HIV-infected subjects, especially in countries with traditionally high intakes of n-6 PUFA-rich vegetable oils.     

Fasting whole blood as a biomarker of essential fatty acid intake in epidemiologic studies: comparison with adipose tissue and plasma

Biomarkers could provide a more accurate measure of long-term intake than questionnaires. Adipose tissue is considered the best indicator of long-term essential fatty acid intake, but other tissues may prove equally valid. The authors evaluated the ability of fasting whole blood, relative to fasting plasma and adipose tissue, to reflect fatty acid intake. Costa Rican men (n = 99) and women (n = 101) completed a 135-item food frequency questionnaire and provided adipose tissue and blood samples from 1999 to 2001. Fatty acids were identified by using capillary gas chromatography. Correlation coefficients adjusted for age, sex, and body mass index were calculated. Diet-tissue correlation coefficients for alpha-linolenic acid and linoleic acid, respectively, were 0.38 and 0.43 in whole blood, 0.51 and 0.52 in adipose tissue, and 0.39 and 0.41 in plasma. High correlations were observed between whole-blood alpha-linolenic and linoleic acid and adipose tissue (r = 0.59 and r = 0.67) and plasma (r = 0.96 and r = 0.88), respectively. Results show that fasting whole blood is a suitable biomarker of long-term essential fatty acid intake, and its performance is comparable to that of fasting plasma. Thus, fasting whole blood could be the sample of choice in epidemiologic studies because of its ability to predict intake, its accessibility, and minimum sample processing.     

Abdominal vs buttock adipose fat: relationships with children's serum lipid levels

OBJECTIVE: To explore the extent to which the reported unfavorable fatty acid content of abdominal depots in adults is also true for children. In addition, the present study aims to assess the relative importance of abdominal vs buttock adipose tissue fat in the prediction of serum lipid levels in children. DESIGN: A cross-sectional study of children from the island of Crete. SETTING: The study was conducted between October 1999 and January 2000 in the Municipality of St Nikolas, Crete. SUBJECTS: A total of 475 children (aged 11-18) participated in the study. Data were obtained on children's anthropometry, serum lipids, physical activity and abdominal and buttock adipose tissue fatty acids. In total 138 children (aged 11-16) had complete data in all of the variables studied. RESULTS: Abdominal depots have elevated proportions of saturated fatty acids (P<0.001) and trans fatty acids (P<0.001), and reduced proportions of monounsaturated (P<0.001) and polyunsaturated fatty acids (P<0.001) in comparison to buttock depots. Buttock adipose tissue monounsaturated fat correlated negatively to serum LDL-C (P<0.05). Abdominal adipose tissue polyunsaturated fat had negative correlations with serum total cholesterol (P<0.05) and LDL-C (P<0.05). Regression analyses indicated that children's serum total cholesterol (P<0.05) and LDL-C (P<0.05) were inversely related to abdominal adipose tissue polyunsaturated fat. Body mass index was positively related to serum triglycerides (P<0.01) and LDL-C (P<0.01), and negatively to serum HDL-C (P<0.05). Age was negatively related to serum HDL-C (P<0.05). CONCLUSIONS: It appears that, similar to adults, children's fatty acid composition of abdominal adipose tissue is less favorable than that of the buttock. Abdominal depots have elevated proportions of saturated fatty acids and reduced proportions of monounsaturated and polyunsaturated fat in comparison to buttock depots. Moreover, children's abdominal depots appear to have higher trans fatty acid contents than buttock depots. Children's adipose polyunsaturated fat, a biomarker of long-term polyunsaturated fatty acid intake, is inversely related to serum total cholesterol and LDL-C. It appears that abdominal adipose tissue fatty acids are more strongly related to serum lipids than buttock adipose tissue fatty acids. This may be attributed to the reported higher lipolysis rates in abdominal as opposed to buttock depots. SPONSORSHIP: Funding was provided by the Municipality of St Nikolas, Crete, Greece.     

Elevated concentrations of linoleic acid in erythrocyte membrane phospholipids in patients with inflammatory bowel disease

Inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn disease (CD), is a disorder characterized by diffuse inflammation of the gastrointestinal tract. The immune response and inflammation are mediated by polyunsaturated fatty acids and influenced by dietary fats and lipid metabolism. This study examined the qualitative and quantitative fat intake of IBD patients and healthy controls on plasma phospholipid and erythrocyte membrane phospholipid (EMP) fatty acid content. Measurement of the fatty acid composition of plasma phospholipid and EMP were performed in 29 UC patients, 20 CD patients, and 31 healthy controls. Anthropometric characteristics and data on dietary intake were also collected. We observed significantly lower lipid intake in UC and CD patients vs controls. The UC and CD patients had significantly higher levels of linoleic acid in their EMP than did controls. There were no significant differences in the levels of n-3 polyunsaturated fatty acids, but there were significantly higher levels of the n-6 in the EMP of UC and CD patients compared with controls. The significant differences persisted after the data were adjusted for potential confounders and lipid intake. Higher levels of linoleic acids and n-6 fatty acids, which are involved in production of proinflammatory mediators, were found in IBD patients compared with controls, thereby implicating n-6 fatty acids in the pathophysiology of the disease.     

Serum fatty acid, lipid profile and dietary intake of Hong Kong Chinese omnivores and vegetarians

OBJECTIVE: To examine the serum fatty acid and lipid profiles and dietary intake of Hong Kong Chinese omnivores and vegetarians with respect to cardiovascular health. DESIGN: Random population survey stratified by age and sex. SUBJECTS: One-hundred and ninety-four omnivore subjects (81 men, 113 women) age 25-70 y, and 60 ovo-lacto-vegetarian adults (15 men, 45 women) age 30-55 y. MEASUREMENTS: Nutrient quantitation was by a food frequency method. Serum fatty acids were analysed by gas chromatography, and serum lipid by standard laboratory methods. RESULTS: Compared with omnivores, vegetarians had higher serum concentrations of polyunsaturated (PUFA) and monosaturated fatty acids (MUFA), and lower saturated fatty acids (SFA), long chain omega-3 and trans fatty acids (TFA). They also had lower serum cholesterol and higher apoA-1 concentrations, but the LDL/HDL ratio was not different. The ratio of polyunsaturated to saturated fatty acids intake was higher in vegetarians. Compared with results from populations with higher incidences of coronary heart disease, while lower myristic and palmitic acid concentrations and higher eicosapentaneoic (EPA) and docosahexanoic acid (DHA) may partly account for the difference in incidence, linoleic acid concentration was higher. Although the Chinese vegetarian diet may be beneficial for heart health in that antioxidant and fibre intakes are higher and saturated fat lower, the low EPA and DHA due to omission from dietary source and suppressed formation by high linoleic acid level, and the presence of TFA in the diet, may exert an opposite effect. CONCLUSION: There are some favourable features in the serum fatty acid profile in the Hong Kong Chinese population with respect to cardiovascular health, but the consumption of TFA is of concern. The Chinese vegetarian diet also contains some adverse features.