Search

ObjectiveTo examine (i) whether the consumption of fresh vegetables, fruit and berries is associated with plasma vitamin C concentration and (ii) educational differences in plasma vitamin C concentration in two neighbouring areas in Russia and Finland.DesignCross-sectional risk factor surveys in 1992, 1997 and 2002. Logistic regression analysis was applied to examine the associations of consumption of selected foods and education with plasma vitamin C concentration.SettingDistrict of Pitkäranta in the Republic of Karelia, Russia and North Karelia, Finland.SubjectsAdults aged 25–64 years: 579 men and 612 women in Pitkäranta; 974 men and 642 women in North Karelia.ResultsThe plasma vitamin C concentration was strikingly low in Pitkäranta, Russia across the study years. During the 10 years of monitoring, the mean plasma vitamin C concentration among men ranged from 2·5 to 8·0 μmol/l in Pitkäranta, Russia and from 27·1 to 53·9 μmol/l in North Karelia, Finland. In both areas, daily consumption of fruit was most strongly associated with plasma vitamin C, while the association of fresh vegetable consumption with plasma vitamin C was less consistent. Consumption of berries was less important in explaining plasma vitamin C. In Pitkäranta, the plasma vitamin C concentration was lower among respondents in the lowest education group.ConclusionsDifferences in the consumption of fresh vegetables and fruit resulted in notable differences in vitamin C status between Pitkäranta and North Karelia in spring. In comparative settings, knowledge of local food culture and validation pilots are important before conducting large population surveys.

Article, Background Vegetarian and vegan diets have become more popular among adolescents and young adults. However, few studies have investigated the nutritional status of vegans, who may be at risk of nutritional deficiencies. Objective To compare dietary intake and nutritional status of Finnish long-term vegans and non-vegetarians. Methods Dietary intake and supplement use were estimated using three-day dietary records. Nutritional status was assessed by measuring biomarkers in plasma, serum, and urine samples. Vegans’ (n = 22) data was compared with those of sex- and age-matched non-vegetarians (n = 19). Results All vegans adhered strictly to their diet; however, individual variability was marked in food consumption and supplementation habits. Dietary intakes of key nutrients, vitamins B12 and D, were lower (P < 0.001) in vegans than in non-vegetarians. Nutritional biomarker measurements showed lower concentrations of serum 25-hydroxyvitamin D3 (25(OH)D3), iodine and selenium (corrected for multiple comparisons, P < 0.001), Vegans showed more favorable fatty acid profiles (P < 0.001) as well as much higher concentrations of polyphenols such as genistein and daidzein (P < 0.001). Eicosapentaenoic acid proportions in vegans were higher than expected. The median concentration of iodine in urine was below the recommended levels in both groups. Conclusions Long-term consumption of a vegan diet was associated with some favorable laboratory measures but also with lowered concentrations of key nutrients compared to reference values. This study highlights the need for nutritional guidance to vegans., published version, http://purl.org/eprint/status/PeerReviewed

Fatty acid concentrations in blood are potential biomarkers of dietary fat intake, but methodological studies among children are scarce. The large number of fatty acids and their complex interrelationships pose a special challenge in research on fatty acids. Our target was to assess the interrelationships between the total fatty acid profiles in diet and serum of young children. The study subjects were healthy control children from the birth cohort of the Type 1 Diabetes Prediction and Prevention Study. A 3-day food record and a frozen serum sample were available from 135 children at the age of 1 year, from 133 at 2 years, and from 92 at 3 years. The relationship between dietary and serum fatty acid profiles was analysed using canonical correlation analysis. The consumption of fatty milk correlated positively with serum fatty acids, pentadecanoic acid, palmitic acid and conjugated linoleic acid (CLA) at all ages. Correlations between dietary and serum eicosapentaenoic and/or docosahexaenoic acid were observed at 2 and 3 years of age. Serum linoleic acid was positively associated with the consumption of infant formula at the age of 1 year, and with the consumption of vegetable margarine at 2 and 3 years. The results indicate a high quality of the 3-day food records kept by parents and other caretakers of the children, and suitability of non-fasting, un-fractioned serum samples for total fatty acid analyses. The correlation between intake of milk fat and serum proportion of CLA is a novel finding.

Periodontitis and Chlamydia pneumoniae infection are independent risk factors for cardiovascular diseases. The aim of this study was to investigate the effect of C. pneumoniae and Aggregatibacter actinomycetemcomitans infection on hepatic inflammation and lipid homeostasis of apolipoprotein E-deficient mice. Mice were infected with viable C. pneumoniae intranasally three times for chronic infection or once for acute infection. Viable A. actinomycetemcomitans was administered 10 times intravenously alone or in concert with C. pneumoniae . Hepatic alterations were assessed by histochemistry, lipid quantification, and fatty acid profile analysis. The RNA expression levels and the presence of pathogens in the livers and lungs were detected by quantitative real-time PCR. Both pathogens were detected in the livers of the infected animals. Chronic C. pneumoniae infection induced marked changes in hepatic lipid homeostasis. A. actinomycetemcomitans infection resulted in inflammatory cell infiltration into the liver, accompanied by elevated hepatic RNA expression levels of inflammation-related genes and higher serum amyloid A and lipopolysaccharide concentrations. Our results indicate that proatherogenic pathogens infect the liver, causing proinflammatory alterations and lipid disturbances. This infection may maintain chronic systemic inflammation attributable to atherogenesis.

Objectives: To introduce a procedure to validate an ascorbic acid method using trichloroacetic acid (TCA) for plasma stabilization at different storage temperatures. Methods: EDTA and heparin plasma were precipitated with TCA (1:5) containing 0.54 mol/L EDTA, or without. Samples were stored at − 20 °C and − 70 °C and their stability was tested at room temperature for 24 h. Results: A significant 40% loss (p

Background/Objectives:Data on associations between marine n-3 fatty acids and glucose metabolism are inconsistent. Therefore, we explored effects of the Pro12Ala polymorphism in peroxisome proliferator-activated receptor (PPAR)-gamma2 gene on associations of fish intake and dietary and plasma eicosapentaenoic and docosahexaenoic acid with glucose metabolism. The design comprises of the cross-sectional analysis.Subjects/Methods:The Pro12Ala variant in the PPAR-gamma2 (PPARG) gene was genotyped in 571 non-diabetic relatives of subjects with type II diabetes. The dietary intake was measured by a 3-day food record, and the plasma cholesterol ester fatty acid composition was analysed with gas chromatography. Associations of dietary and plasma variables with insulin resistance and fasting and 2-h glucose and free fatty acid concentrations were analysed with multiple linear regression analysis.Results:In men, there was a significant interaction between PPARG polymorphism and plasma docosahexaenoic acid on fasting free fatty acid concentration (P=0.036), and genotype-stratified models showed an inverse association in Pro homozygotes only (P=0.028). In women, the proportion of plasma eicosapentaenoic acid was higher in Ala-allele carriers compared to Pro homozygotes (1.67 vs 1.44% respectively, P=0.006). A significant interaction between PPARG polymorphism and fish intake on 2-h glucose was found in women (P=0.021), and genotype-stratified models suggested an inverse association in Ala-allele carriers only (P=0.039).Conclusions:The findings suggest that PPARG polymorphism might affect the plasma proportion of eicosapentaenoic acid and modulate the associations of fish intake and marine n-3 fatty acids with glucose metabolism and fasting free fatty acids.European Journal of Clinical Nutrition advance online publication, 15 August 2007; doi:10.1038/sj.ejcn.1602882. (Less)

Flaxseed is a dietary source of possible chemopreventive compounds such as lignans and α-linolenic acid (ALA). To study the effects of a flaxseed mixture on adenoma formation in multiple intestinal neoplasia mice, the mice were fed a diet containing 2·7 % flaxseed, 4·5 % fibre and 3·7 % ALA. To elucidate the effect of oils of the mixture we also composed a diet without flaxseed but with the same oil composition. The median number of adenomas in the small intestine was fifty-four for the control group, and thirty-seven (P=0·023) and forty-two (P=0·095) for flaxseed and oil groups, respectively. Compared with controls (1·2 mm), the adenoma size was smaller in the flaxseed (0·9 mm; P=0·002) and oil (1·0 mm; P=0·012) groups. Both diets changed the proportions of n-3 and n-6 fatty acids in the colonic mucosa. Membrane β-catenin and protein kinase C (PKC)-ζ levels were reduced in the adenoma v. mucosa (Pr −0·460, P=0·008, n 32). Only the flaxseed diet increased lignan levels in the caecum (P=0·002) and in plasma (P=0·002) but they were not associated with tumour formation. The results suggest that the preventive effect of flaxseed on colon carcinogenesis may be due to the oil part of flaxseed, and the loss of β-catenin and PKC-ζ from the membranes of the mucosal tissue may play a permissive role in intestinal tumour development.

Background: Dietary fat has been reported to influence insulin sensitivity. Objective: The objective of the study was to determine how identical weight loss (target: loss of 8% of body weight over 3–6 mo) in women taking orlistat or placebo combined with a hypocaloric diet influences body composition and insulin sensitivity. Design: Forty-seven obese women [body mass index (in kg/m 2 ): 32.1 0.4] were randomly assigned to receive either orlistat (120 mg 3 times daily; n 23) or placebo (n 24) with a hypocaloric diet. Whole-body insulin sensitivity (insulin clamp technique), serum fatty acids, and body composition (magnetic resonance imaging) were measured before and after weight loss. Results: The groups did not differ significantly at baseline with respect to age, body weight, intraabdominal and subcutaneous fat volumes, or insulin sensitivity. Weight loss did not differ significantly between the orlistat (7.3 0.2 kg, or 8.3 0.1%) and placebo (7.4 0.2 kg, or 8.2 0.1%) groups. Insulin sensitivity improved significantly (P 0.001) and similarly after weight loss in the orlistat (from 4.0 0.3 to 5.1 0.3 mg kg fat-free mass 1 min 1 ) and placebo (from 4.4 0.4 to 5.4 0.4 mg kg fat-free mass 1 min 1 ) groups. Intraabdominal fat and subcutaneous fat decreased significantly in both groups, but the ratio of the 2 decreased significantly only in the orlistat group. The proportion of dihomo--linolenic acid (20:3n6) in serum phospholipids was inversely related to insulin sensitivity both before ( r 0.48, P 0.001) and after (r 0.46, P 0.001) weight loss, but it did not change significantly in either group. Conclusions: Weight loss rather than inhibition of fat absorption enhances insulin sensitivity. A decrease in fat absorption by orlistat appears to favorably influence the ratio between intraabdominal and subcutaneous fat, which suggests that exogenous fat or its composition influences fat distribution. Am J Clin Nutr 2004;79: 22–30.

Conjugated linoleic acid (CLA) is a term used to describe the different conjugated isomers of linoleic acid. CLA has been found to be anticarcinogenic in mammary cancer, but its effects on colon carcinogenesis are still inconclusive. In this study, the isomer-specific effects of the cis-9, trans-11 and trans-10, cis-12 CLA isomers were investigated in the Min mouse model for intestinal carcinogenesis. The Min mice (n = 10/group) were fed either an AIN-93G control diet or a diet containing 1 g/100 g cis-9, trans-11 or trans-10, cis-12 CLA for 8 wk. The number and size of adenomas were measured and the proteins from the small intestinal tissues extracted for immunoblotting analysis. The number of adenomas did not differ, but the size of the adenomas was greater in the distal part of the small intestine in mice fed the trans-10, cis-12 isomer than in controls (1.19 +/- 0.16 vs. 0.94 +/- 0.21 mm, mean +/- SD, P < 0.01). The same isomer caused an increase in lipid peroxidation, measured as urinary 8-iso-prostaglandin (PG)F(2alpha). Nuclear p65 protein of the mucosal tissue was not detectable in the trans-10, cis-12 group, which differed (P < 0.05) from the control group. Cyclin D1, a target for the nuclear factor (NF)-kappaB pathway, was elevated in the trans-10, cis-12 group compared with the control group (P < 0.01), but cyclooxygenase-2 levels were not higher. There was no difference in beta-catenin protein levels between the groups. The results indicate that the trans-10, cis-12 isomer of CLA can act as a cancer promoter in colon carcinogenesis possibly through pathways affecting NF-kappaB and cyclin D1.

Objective: The purpose was to study the effects of flaxseed supplementation as a part of daily diet on serum lipids, fatty acids and plasma enterolactone. Design: Eighty volunteers participated in this clinical nutrition study which was carried out in a controlled, double-blind and cross-over manner. The subjects were randomized to diet sequences AB or BA. Diet A meals contained 1.3 g/100 g ground flaxseed and 5 g/100 g flaxseed oil. Also 3–4 g/100 of inulin and wheat fiber was added. AB diet with non-supplemented foods served as control. Test subjects were on both diets for 4 weeks separated by a 4-week wash-out period. Fifteen test subjects continued an open part of the study for 4 additional months. Interventions: The dietary intake, basic blood values, serum lipids, fatty acids and enterolactone were measured at baseline, after both intervention periods and during the open study, at baseline and after 2 and 4 months. Serum thiocyanate and blood cadmium were controlled after both intervention periods. Results: The percentage of flaxseed supplemented test food out of total dietary intake was 20% of energy. The test food contained significantly higher amounts of fiber, polyunsaturated fatty acids (PUFAs) and especially α-linolenic acid than the control food. No significant changes were observed in the basic laboratory values or in blood lipids. There was a significant increase in serum α-linolenic acid, eicosapentaenoic acid and docosapentaenoic acid. Serum enterolactone concentration was doubled during flaxseed supplementation. Serum thiocyanate and blood cadmium values did not exceed reference values and there was no difference between the diets. Conclusions: In this study we were able to show that, by adding ground flaxseed and flaxseed oil to one or two daily meals, it is possible to obtain significant effects on serum levels of enterolactone and α-linolenic acid. Sponsorship: The study was sponsored by the National Technology Agency of Finland (Tekes).

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.

Conjugated linoleic acid (CLA), fatty acids with 18 carbon atoms and two conjugated cis/trans double bonds, have shown anticarcinogenic effects in experimental studies. We determined the proportion of CLA (the sum of cis-9, trans-11 and trans-9, cis-11 CLA) of total fatty acids in the diets and serum samples of healthy subjects who consumed for 5 weeks a diet high in saturated fatty acids mainly from dairy fat, followed by 5 weeks on a diet high (8.7% of energy, en%) in trans fatty acids from partially hydrogenated vegetable oil (40 subjects) or a similar diet high in stearic acid (9.3 en%, 40 subjects). All diets contained equal amounts of fat and cis-monounsaturated and cis-polyunsaturated fatty acids. The fatty acid compositions of the pooled diets and fasting serum samples drawn at the end of the diet periods were analyzed by gas chromatography, and CLA was identified by comparison with a standard of C18:2 conjugated dienes. The proportions of CLA in the dairy fat, trans fatty acid, and stearic acid diets were 0.37, 0.04, and 0.10% of total methylated fatty acids, respectively. The corresponding mean (SD) proportions in serum were 0.33 (0.07)% after the dairy fat diet, higher, 0.43 (0.12)%, P < 0.001, after the trans fatty acid diet, and lower, 0.17 (0.06)%, P < 0.001, after the stearic acid diet. The difference between dairy fat and stearic acid diets was explained by different dietary intakes but increased amounts of CLA not present in the diet were incorporated into serum lipids during the trans fatty acid diet. CLA in human tissues is partly derived from the diet but part of it may be formed by conversion from dietary trans fatty acids.

A low serum tocopherol concentration and a low proportion of linoleic acid in plasma cholesterol esters have been reported to be associated with coronary heart disease. This study was undertaken to evaluate the predictive importance of the serum cholesterol ester fatty acid composition and serum tocopherol concentration in addition to established risk factors for myocardial infarction. The study comprised 2322 fifty-year-old men who participated in a health survey in 1970–1973 regarding risk factors for coronary heart disease. The proportions of myristic, palmitic, palmitoleic, and dihomogammalinolenic acid were significantly higher in 1970–1973 in subjects who suffered myocardial infarction during the following 19 years, while the proportion of linoleic acid was lower, than in those who remained healthy. Serum tocopherol did not differ significantly between the groups. LDL HDL ratio, systolic blood pressure, and arachidonic acid/dihomogammalinolenic acid ratio were significant independent discriminators between cases and controls in a stepwise logistic regression analysis. This study suggests that middle-aged men who later develop a myocardial infarction are characterized not only by conventional risk factors but also by an altered fatty acid composition of serum cholesterol esters, with a low arachidonic to dihomogammalinolenic acid ratio, indicating reduced Δ 5 desaturase activity. This may imply that changes in the quality of dietary fat intake, or an altered capacity to metabolize fatty acids in the body, could precede the development of coronary heart disease.

In the 1990s, extremely low plasma vitamin C concentrations were reported in the district of Pitkaranta, Northwestern Russia, during springtime in connection to population-risk factor surveys.1, 2 The surveys were conducted in springtime, when the supply of fresh vegetables and fruit in the area was remarkably poor. As the consumption of vitamin C-rich foods like vegetables, fruit and berries varies across seasons,3 it can be assumed that levels of plasma vitamin C vary as well.

SummaryThe effect of dietary linoleic/α-linolenic acid ratio on human platelet aggregation in vitro was investigated using low-erucic acid rapeseed oil and high-oleic acid sunflower oil as the major fat sources. In a cross-over study 20 healthy male subjects, average age 29 year (range 20–46 yr), followed experimental rapeseed oil (RO) and Trisun-sunflower oil (TSO) diets after their habitual diet for six weeks. Subjects were provided most of the fat containing foods but were allowed to eat other foods almost freely. Fatty acid compositions of the diets calculated from dietary records were as follows (saturated/monounsaturated/polyunsaturated fatty acids): RO diet 12.4/18.6/8.9% of total energy (en%) (linoleic/α-linolenic acid ratio 2.8) and TSO diet 11.8/17.8/8.3 en% (linoleic/α-linolenic acid ratio 28), respectively. Plasma cholesterol ester fatty acid composition proved compliance to the experimental diets. Platelet aggregations induced by ADP (1,2 and 3 μM) or thrombin (0.12, 0.15 and 0.18 NIH/ml) were significantly enhanced and collagen- (1.5, 2.5 and 5.0 μg/ml) induced aggregation tended to be enhanced after the TSO diet compared with the RO diet. After the TSO diet platelet aggregation was enhanced from the level of the habitual diets by one thrombin (0.18 NIH/ml), one collagen (1.5 μg/ml) and all three ADP concentrations. The diets had no effect on antithrombin III activity. Results show that platelet aggregation in vitro decreases as the ratio of linoleic acid to a-linolenic acid decreases in diets rich in monounsaturated fatty acids.

N-3 (omega-3) fatty acids have been reported to decrease the risk for development of beta-cell autoimmunity and clinical type I diabetes. We set out to examine whether different serum fatty acids are associated with the development of advanced beta-cell autoimmunity in children carrying human leukocyte antigen DQ beta-1 (HLA-DQB1)-conferred susceptibility to type I diabetes.Within a cohort, serum total fatty acid composition of 108 children with advanced beta-cell autoimmunity and of 216 matched persistently autoantibody-negative controls was analyzed using gas chromatography. Non-fasting serum samples were obtained annually at the ages of 1-6 years. Conditional logistic regression was applied to analyze the associations between advanced beta-cell autoimmunity and serum fatty acids.The serum fatty acid profile of myristic acid (odds ratio (OR) 1.48, 95% confidence interval (CI) 1.09-2.00, P=0.011), pentadecanoic acid (OR 1.65, 95% CI 1.19-2.28, P=0.003), palmitoleic acid isomers 16:1 n-7 (omega-7) (OR 1.41, 95% CI 1.03-1.92, P=0.030) and 16:1 n-9 (omega-9) (OR 1.45, 95% CI 1.05-2.01, P=0.026) and conjugated linoleic acid (OR 1.67, 95% CI 1.16-2.41, P=0.006) closest to the time of the appearance of multiple autoantibodies were positively associated with the risk of advanced beta-cell autoimmunity after adjustment for potential confounding factors. Serum linoleic acid showed inverse, marginal association with the end point.Serum biomarkers of milk and ruminant meat fat consumption are directly associated and linoleic acid is inversely associated with advanced beta-cell autoimmunity in children with HLA-conferred susceptibility to type I diabetes.

There is some evidence that alpha-linolenic acid might be positively related to prostate cancer risk. Associations between serum fatty acid composition as well as fatty acid intakes and prostate cancer risk were examined in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study. The cohort included 29,133 male smokers aged 50-69 years. During 5-8 years of follow-up, 246 prostate cancer cases were diagnosed. One control was selected and matched by age (+/- 1 month) for each case from the cohort subjects alive and free of prostate cancer at the time the case was diagnosed. This study included 198 case-control pairs with baseline serum sample available for both. Fatty acids of serum cholesterol esters were measured as a percentage of total fatty acids, using capillary gas chromatography. Intakes of fatty acids were assessed from a validated self-administered dietary questionnaire. Serum and dietary fatty acids had no consistent association with prostate cancer risk. Serum alpha-linolenic acid was not related to prostate cancer risk. Twofold risk was found in the highest quartile of serum myristic acid compared with the lowest quartile (odds ratio, 1.93; 95% confidence interval, 1.02-3.64). alpha-Tocopherol supplementation modified the association between serum linoleic acid and prostate cancer risk (P for interaction 0.03); odds ratio was 0.17 (95% confidence interval, 0.04-0.68) in the highest quartile of serum linoleic acid compared with the lowest quartile in men who received alpha-tocopherol, whereas no association was found in men who did not receive alpha-tocopherol. In conclusion, we found no overall association between serum or dietary alpha-linolenic acid or any other unsaturated fatty acid and prostate cancer risk, but high serum linoleic acid was associated with lower risk in men supplemented with alpha-tocopherol. High serum myristic acid associated with an increased risk of prostate cancer.

Camelina sativa-derived oil (camelina oil) is a good source of alpha-linolenic acid. The proportion of alpha-linolenic acid in serum fatty acids is associated with the risk of cardiovascular diseases. We studied the effects of camelina oil on serum lipids and on the fatty acid composition of total lipids in comparison to rapeseed and olive oils in a parallel, double-blind setting. Sixty-eight hypercholesterolemic subjects aged 28 to 65 years were randomly assigned after a 2-week pretrial period to 1 of 3 oil groups: camelina oil, olive oil, and rapeseed oil. Subjects consumed daily 30 g (actual intake, approximately 33 mL) of test oils for 6 weeks. In the camelina group, the proportion of alpha-linolenic acid in fatty acids of serum lipids was significantly higher (P

Background Vaccenic acid (11-trans octadecenoic acid; VA), a major trans fatty acid in the fat of ruminants, is produced in the rumen and converted in tissues to rumenic acid (9-cis, 11-trans octadecenoic acid; RA), an isomer of conjugated linoleic acid, by Delta(9)-desaturase. There are indications that this conversion also occurs in humans. Objective The aim of this controlled intervention was to study the conversion of VA to RA in humans after consumption of diets with increasing amounts of VA. Design Thirty healthy subjects consumed a baseline diet rich in oleic acid for 2 wk. The subjects were then divided into 3 groups (n = 10 per group) and provided a diet containing 1.5, 3.0, or 4.5 g VA/d for 9 d. All diets contained equal amounts of macronutrients and differed only in their fatty acid compositions. The fats were mixed into conventional foods, and nearly all food was provided during the study. Results The proportion of VA in serum total fatty acids increased 94%, 307%, and 620% above baseline with the 1.5-, 3.0-, and 4.5-g diets, respectively. This was associated with a linear increase in the proportion of RA. The conversion rate was 19% on average, with significant interindividual differences with all 3 intakes of VA. The urinary excretion of 8-iso-prostaglandin F(2alpha) increased in all groups (P Conclusions The results quantify the desaturation of VA to RA in humans. Conversion is likely to contribute significantly to the amount of RA available to the body, and dietary intakes of VA should thus be taken into account when predicting RA status.

Conjugated linoleic acid (CLA) is anticarcinogenic in experimental animal studies. We studied dietary and serum CLA in Finnish patients with breast cancer in 1992-1995. Participants were consecutive women with breast cancer (68 premenopausal and 127 postmenopausal) and population-based control women (75 premenopausal and 133 postmenopausal), matched for age and area of residence. Diet was assessed by a validated food frequency questionnaire and the fatty acid composition of serum by gas-liquid chromatography. In postmenopausal women, dietary CLA, serum CLA, myristic acid, and trans-vaccenic acid were significantly lower in cases than in controls. The odds ratio for breast cancer in the highest quintile vs. the lowest was 0.4 [95% confidence interval (CI) = 0.2-0.9]for CLA, 0.3 (95% CI = 0.1-0.7) for myristic acid, and 0.3 (95% CI = 0.1-0.7) for trans-vaccenic acid in serum. The odds ratios remained similar after adjustment for known risk factors of breast cancer. A diet composed of CLA-rich foods, particularly cheese, may protect against breast cancer in postmenopausal women, but it is impossible to assess the independent effects of CLA in this study. The findings may be of relevance for food production, inasmuch as it is possible to increase CLA and its precursor trans-vaccenic acid in foods by modifying the feeding of ruminants.

To compare the effects on serum lipoproteins of stearic acid, trans fatty acids, and dairy fat, 80 healthy subjects consumed a dairy fat-based (baseline) diet for 5 wk, then an experimental diet high in either trans fatty acids (8.7% of energy; n = 40) or stearic acid (9.3% of energy; n = 40) for another 5 wk. All diets provided 32.2-33.9% of energy as fat, 14.6-15.8% as saturated plus trans fatty acids, 11.4-12.5% as cis-monounsaturated fatty acids, 2.9-3.5% as polyunsaturated fatty acids, and 200-221 mg cholesterol/10 MJ. Compared with the dairy fat diet, stearic acid and trans fatty acids decreased serum total cholesterol concentrations similarly (by 13% and 12%, respectively, P < 0.001) but the trans fatty acid diet decreased HDL cholesterol (17%) and apolipoprotein (apo) A-I (15%) significantly more than did the stearic acid diet (11% and 12%, respectively). Stearic acid but not trans fatty acids reduced concentrations of LDL cholesterol and apo B significantly (P < 0.001). The trans fatty acid diet increased the ratio of LDL to HDL cholesterol (19%) and of apo B to apo A-I (16%) more than did the dairy fat diet (P < 0.001) but the stearic acid diet had no effect. Lipoprotein(a) concentrations increased with both experimental diets, significantly more with trans fatty acids (30%) than with stearic acid (10%). In conclusion, high amounts of trans fatty acids had more adverse effects on lipoproteins than did equal amounts of stearic acid and dairy fat. Stearic acid reduced LDL cholesterol, did not affect the ratio of LDL to HDL cholesterol, and increased lipoprotein(a), although to a lesser extent than did trans fatty acids. Dietary fats low in both saturated fatty acids and trans fatty acids should be favored.

Abstract It has been suggested that the fatty acid composition of serum phospholipids is an independent risk factor for cardiovascular disease. We examined the association of the fatty acid composition of serum phospholipids with fibrinogen, factor VII antigen (FVII:Ag), factor VII coagulant activity (FVII:C), plasminogen, and lipoprotein(a) [Lp(a)] in 338 men and 363 women 45 to 64 years old. Palmitic acid, the most abundant saturated fatty acid, was positively associated in univariate analyses with plasminogen, which explained 5.2% of its variance among men ( P P P =.04) and 3.2% among women ( P =.0006) and 4.1% of the variance in plasminogen in both sexes ( P P =.0003) and 4.6% among women ( P

Background Chronic infections have been demonstrated to maintain low-grade systemic inflammation and associate with atherosclerosis. We studied the inflammation- and lipid homeostasis-related effects of Aggregatibacter actinomycetemcomitans (Aa) and Chlamydia pneumoniae (Cpn) infections on the epididymal and inguinal adipose tissue (AT) transcriptomes and fatty acid distribution in apolipoprotein (apo) E-deficient mice. Chow-fed apoE-deficient mice were exposed to 1) chronic intranasal infection with C. pneumoniae (Cpn group), 2) recurrent intravenous infection with A. actinomycetemcomitans (Aa group), 3) a combination of both types of infection (Cpn + Aa group), or 4) infection with the vehicle (control group). Epididymal and inguinal AT gene expression was analyzed using an Illumina Mouse WG-6 v2.0 platform and quantitative PCR (QPCR). Microarray data were analyzed using Gene Ontology enrichment analysis. AT fatty acid analysis was performed using gas–liquid chromatography. Results The transcriptomics data revealed significant enrichment in inflammation-associated biological pathways in both AT depots derived from the Aa and Cpn + Aa treated mice compared with the control group. The proportion of saturated fatty acids was higher in the inguinal AT in Aa (p = 0.027) and Cpn + Aa (p = 0.009) groups and in the epididymal AT in Aa group (p = 0.003). The proportion of polyunsaturated fatty acids was significantly lower among all Aa-infected groups in both depots. Chronic Cpn infection displayed only minor effects on transcriptomics and fatty acids of the AT depots. Conclusions Systemic infection with A. actinomycetemcomitans activates inflammation-related biological pathways and modulates cellular lipid homeostasis. The adverse changes in adipose tissues during chronic infection may promote atherosclerosis.

This investigation was undertaken to study whether the risk to develop non-insulin-dependent diabetes mellitus (NIDDM) among 50-year-old men during a 10-year follow-up period was related to the fatty acid composition of their serum cholesterol esters. There were highly significant differences in the initial health survey between the fatty acid composition in serum in subjects who remained normoglycemic (n = 1,753) and in those who later developed NIDDM (n = 75). The main differences were that the latter had higher proportions of saturated fatty acids and palmitoleic acid (16:1 omega-7), a low proportion of linoleic acid (18:2 omega-6), and a relatively high content of gamma-linolenic (18:3 omega-6) and dihomo-gamma-linolenic (20:3 omega-6) acids in the serum cholesterol esters. The picture was similar also after adjusting for differences in body mass index. In a logistic model, a high proportion of dihomo-gamma-linolenic acid remained a significant contributor to the development of diabetes, along with the height of the insulin index, the blood glucose concentration at 60 min, and the fasting insulin concentration. The increased risk to develop NIDDM related to the serum cholesterol ester fatty acid composition may be mediated by diet and/or genetic factors.

CLA intake in exclusively breast-fed infants is close to levels found to have physiological effects in animals. However, in the majority of studies mixtures of CLA isomers have been used and the independent effects of the major CLA isomer in human milk, cis-9,trans-11 CLA, at the intake level in exclusively breast-fed infants have hardly been studied. We therefore studied the effects of cis-9,trans-11 CLA on plasma lipids and glucose, immune function, and bone metabolism in growing rats. Thirty male Sprague-Dawley rats (n = 10/group) were fed either 20 mg/kg/d cis-9,trans-11 CLA and 20 mg/kg/d sunflower oil (CLA20), 40 mg/kg/d cis-9,trans-11 CLA (CLA40), or 40 mg/kg/d sunflower oil (placebo) for 8 wk. No significant differences between groups were found in plasma lipids, glucose, insulin, C-reactive protein, or lipid peroxidation. Liver fat content was lowest in the CLA20 group. In vitro interleukin 2 (IL-2) production increased, and tumor necrosis factor alpha, IL-1beta, prostaglandin E2, and leukotriene B4 production decreased in the CLA20 group. No differences between groups were detected in IL-4, IL-6, or interferon gamma production, plasma osteocalcin, insulin-like growth factor, or urinary deoxypyridinoline crosslinks. Plasma tartrate-resistant acid phosphatase 5b activity was significantly increased in the CLA40 group. The results indicate anti-inflammatory effects and enhanced T-cell function for the CLA20 group. No adverse effects were seen in the CLA20 group, whereas indications of increased bone resorption rate were observed in the CLA40 group.