Vitamin D supplementation and prevention of cardiovascular disease and cancer in the Finnish Vitamin D Trial: a randomized controlled trial.

BACKGROUND: Vitamin D insufficiency is associated with risks of cardiovascular diseases (CVD) and cancer in observational studies, but evidence for benefits with vitamin D supplementation is limited. OBJECTIVES: To investigate the effects of vitamin D3 supplementation on CVD and cancer incidences. METHODS: The study was a 5-year, randomized, placebo-controlled trial among 2495 male participants ≥60 years and post-menopausal female participants ≥65 years from a general Finnish population who were free of prior CVD or cancer. The study had 3 arms: placebo, 1600 IU/day, or 3200 IU/day vitamin D3. Follow-up was by annual study questionnaires and national registry data. A representative subcohort of 551 participants had more detailed in-person investigations. The primary endpoints were incident major CVD and invasive cancer. Secondary endpoints included the individual components of the primary CVD endpoint (myocardial infarction, stroke, and CVD mortality), site-specific cancers, and cancer death. RESULTS: During the follow-up, there were 41 (4.9%), 42 (5.0%), and 36 (4.3%) major CVD events in the placebo, 1600 IU/d (compared with placebo: HR: 0.97; 95% CI: 0.63-1.49; P = 0.89), and 3200 IU/d (HR: 0.84; 95% CI: 0.54-1.31; P = 0.44) arms, respectively. Invasive cancer was diagnosed in 41 (4.9%), 48 (5.8%), and 40 (4.8%) participants in the placebo, 1600 IU/d (HR: 1.14; 95% CI: 0.75-1.72; P = 0.55), and 3200 IU/d (HR: 0.95; 95% CI: 0.61-1.47; P = 0.81) arms, respectively. There were no significant differences in the secondary endpoints or total mortality. In the subcohort, the mean baseline serum 25-hydroxyvitamin D concentration was 75 nmol/L (SD, 18 nmol/L). After 12 months, the concentrations were 73 nmol/L (SD, 18 nmol/L), 100 nmol/L (SD, 21 nmol/L), and 120 nmol/L (SD, 22 nmol/L) in the placebo, 1600 IU/d, and 3200 IU/d arms, respectively. CONCLUSIONS: Vitamin D3 supplementation did not lower the incidences of major CVD events or invasive cancer among older adults, possibly due to sufficient vitamin D status in most participants at baseline.

Vitamin D status and the risk of cardiovascular disease death.

Accumulating evidence suggests that inadequate vitamin D levels may predispose people to chronic diseases. The authors aimed to investigate whether serum 25-hydroxyvitamin D (25(OH)D) level predicts mortality from cardiovascular disease (CVD). The study was based on the Mini-Finland Health Survey and included 6,219 men and women aged > or =30 years who were free from CVD at baseline (1978-1980). During follow-up through 2006, 640 coronary disease deaths and 293 cerebrovascular disease deaths were identified. Levels of 25(OH)D were determined from serum collected at baseline. Cox's proportional hazards model was used to assess the association between 25(OH)D and risk of CVD death. After adjustment for potential confounders, the hazard ratio for total CVD death was 0.76 (95% confidence interval (95% CI): 0.60, 0.95) for the highest quintile of 25(OH)D level versus the lowest. The association was evident for cerebrovascular death (hazard ratio = 0.48, 95% CI: 0.31, 0.75) but not coronary death (hazard ratio = 0.91, 95% CI: 0.70, 1.18). A low vitamin D level may be associated with higher risk of a fatal CVD event, particularly cerebrovascular death. These findings need to be replicated in other populations. To demonstrate a causal link between vitamin D and CVD, randomized controlled trials are required.

Immunological and metabolic effects of cis-9, trans-11-conjugated linoleic acid in subjects with birch pollen allergy.

Animal studies suggest that conjugated linoleic acid (CLA) may modulate the immune response, while studies in healthy human subjects have shown little effect and results are controversial. However, the effects of CLA may be more prominent in situations of immune imbalance, such as allergy. We studied the effects of the natural CLA isomer, cis-9, trans-11-CLA, on allergy symptoms and immunological parameters in subjects with birch pollen allergy. In a randomised, placebo-controlled study, forty subjects (20-46 years) with diagnosed birch pollen allergy received 2 g CLA/d in capsules, which contained 65.3 % cis-9, trans-11-CLA and 8.5 % trans-10, cis-12-CLA (n 20), or placebo (high-oleic acid sunflower-seed oil) (n 20) for 12 weeks. The supplementation began 8 weeks before the birch pollen season and continued throughout the season. Allergy symptoms and use of medication were recorded daily. Lymphocyte subsets, cytokine production, immunoglobulins, C-reactive protein, lipid and glucose metabolism and lipid peroxidation were assessed before and after supplementation. The CLA group reported a better overall feeling of wellbeing (P < 0.05) and less sneezing (P < 0.05) during the pollen season. CLA supplementation decreased the in vitro production of TNF-alpha (P < 0.01), interferon-gamma (P < 0.05) and IL-5 (P < 0.05). Total plasma IgE and birch-specific IgE concentrations did not differ between groups, whereas plasma IgA (P < 0.05), granulocyte macrophage colony-stimulating factor (P < 0.05) and eosinophil-derived neurotoxin (P < 0.05) concentrations were lower after CLA supplementation. Urinary excretion of 8-iso-PGF2alpha, a major F2-isoprostane (P < 0.01), and 15-keto-dihydro-PGF2alpha, a primary PGF2alpha metabolite (P < 0.05), increased in the CLA group. The results suggest that cis-9, trans-11-CLA has modest anti-inflammatory effects in allergic subjects.

Mercury, fish oils, and the risk of myocardial infarction.

BACKGROUND: It has been suggested that mercury, a highly reactive heavy metal with no known physiologic activity, increases the risk of cardiovascular disease. Because fish intake is a major source of exposure to mercury, the mercury content of fish may counteract the beneficial effects of its n-3 fatty acids. METHODS: In a case-control study conducted in eight European countries and Israel, we evaluated the joint association of mercury levels in toenail clippings and docosahexaenoic acid (C22:6n-3, or DHA) levels in adipose tissue with the risk of a first myocardial infarction among men. The patients were 684 men with a first diagnosis of myocardial infarction. The controls were 724 men selected to be representative of the same populations. RESULTS: The average toenail mercury level in controls was 0.25 microg per gram. After adjustment for the DHA level and coronary risk factors, the mercury levels in the patients were 15 percent higher than those in controls (95 percent confidence interval, 5 to 25 percent). The risk-factor-adjusted odds ratio for myocardial infarction associated with the highest as compared with the lowest quintile of mercury was 2.16 (95 percent confidence interval, 1.09 to 4.29; P for trend=0.006). After adjustment for the mercury level, the DHA level was inversely associated with the risk of myocardial infarction (odds ratio for the highest vs. the lowest quintile, 0.59; 95 percent confidence interval, 0.30 to 1.19; P for trend=0.02). CONCLUSIONS: The toenail mercury level was directly associated with the risk of myocardial infarction, and the adipose-tissue DHA level was inversely associated with the risk. High mercury content may diminish the cardioprotective effect of fish intake.

Intake and adipose tissue composition of fatty acids and risk of myocardial infarction in a male Portuguese community sample.

OBJECTIVE: To evaluate the relation between intake and adipose tissue composition of fatty acids and acute myocardial infarction in Portuguese men. DESIGN: Case-control study. Diet was assessed using a semiquantitative food frequency questionnaire. In 49 case and 49 control subjects, adipose tissue composition was assessed by gas-liquid chromatography. SUBJECTS/SETTING: Population-based; subjects were 297 consecutively admitted cases of first acute myocardial infarction in a tertiary care hospital who were aged>or=40 years. Three hundred ten community controls were selected by random-digit dialing. MAIN OUTCOME MEASURE: Odds ratio (OR). STATISTICAL ANALYSIS PERFORMED: Logistic regression, adjusting for age, education, family history of acute myocardial infarction, smoking, physical activity, body mass index, and energy intake. RESULTS: Total fat intake (OR 0.45, fourth quartile, P=0.02), lauric acid (OR 0.44, fourth quartile, P=0.02), palmitic acid (OR 0.58, fourth quartile, P=0.03), and oleic acid (OR 0.42, fourth quartile, P=0.03) were inversely associated with acute myocardial infarction. No significant effects were found for the remaining fatty acids. In the adipose tissue composition data, the adjusted risk estimates of acute myocardial infarction for the highest vs the lowest tertile were 0.16, 0.14, and 0.04 for lauric, oleic, and trans-fatty acids, respectively. A significant direct association was found for palmitic and linoleic acids (adjusted ORs for the highest tertile were 9.02 and 3.63, respectively). CONCLUSIONS: Low intake of total fat and lauric acid from dairy products was associated with acute myocardial infarction. The association of polyunsaturated fatty acids with risk of acute myocardial infarction was nonsignificant after adjustment for energy intake and confounders. Recommendations on fatty acid intake should aim for both an upper and lower limit.

The scientific basis for trans fatty acid regulations-is it sufficient? A European perspective.

The C18:1 trans fatty acids (TFA) comprise a variety of positional isomers, but no definite differences have been documented so far between the metabolic and health effects of industrial and ruminant TFA. In Europe the intake of industrially produced TFA (IP-TFA) has declined, and the majority of TFA are of ruminant origin. TFA have been replaced with cis-unsaturates in soft margarines and they have been reduced also in industrial fats, but often by using palm kernel oils. When modifying the dietary fat composition the proportion of saturated plus TFA should be kept to one-third of total dietary fatty acid intake.

Dietary fat content modifies liver fat in overweight nondiabetic subjects.

BACKGROUND: Fat accumulation in the liver has been shown to be closely correlated with hepatic insulin resistance and features of insulin resistance, even independent of body weight. The reason for interindividual variation in liver fat content is unknown. Cross-sectional data suggest that dietary fat content may influence liver fat, but this possibility has not been directly tested in humans. DESIGN AND METHODS: Liver fat (proton spectroscopy), intraabdominal and sc fat (magnetic resonance imaging), and markers of insulin sensitivity (insulin, free fatty acids, and lipids) were determined in 10 normal, obese women (age, 43 +/- 5 yr, mean +/- sd; body mass index, 33 +/- 4 kg/m2; range, 27-38 kg/m2) at baseline and after two 2-wk isocaloric periods containing either 16% (low-fat diet) or 56% (high-fat diet) of total energy as fat. RESULTS: Liver fat at baseline averaged 10 +/- 7%. It decreased by 20 +/- 9% during the low-fat diet and increased by 35 +/- 21% during the high-fat diet (P = 0.014 for liver fat after low- vs. high-fat diets; P = 0.042 for change in liver fat by the low- vs. high-fat diet). Fasting serum insulin averaged 70 +/- 41 pmol/liter at baseline. It decreased to 60 +/- 24 pmol/liter during the low-fat diet (P = 0.007 vs. before low-fat diet) and increased to 81 +/- 44 pmol/liter during the high-fat diet (P = 0.040 vs. before high-fat diet; P = 0.005 for change in serum insulin during low- vs. high-fat diet). Serum lipids, free fatty acids, and intraabdominal and sc fat masses were unchanged. CONCLUSION: These data suggest that the amount of dietary fat influences liver fat content.

Changes in dietary fat intake alter plasma levels of oxidized low-density lipoprotein and lipoprotein(a).

OBJECTIVE: To assess the effects of dietary modifications on oxidized low-density lipoprotein (LDL). METHODS AND RESULTS: Thirty-seven healthy women were fed two diets. Both diets contained a reduced amount of total and saturated fat. In addition, one diet was low in vegetables and the other was high in vegetables, berries, and fruit. The dietary intake of total fat was 70 g per day at baseline and decreased to 56 g (low-fat, low-vegetable diet) and to 59 g (low-fat, high-vegetable diet). The saturated fat intake decreased from 28 g to 20 g and to 19 g, and the amount of polyunsaturated fat intake increased from 11 g to 13 g and to 19 g (baseline; low-fat, low-vegetable; low-fat, high-vegetable; respectively). The amount of oxidized LDL in plasma was determined as the content of oxidized phospholipid per ApoB-100 using a monoclonal antibody EO6 (OxLDL-EO6). The median plasma OxLDL-EO6 increased by 27% (P<0.01) in response to the low-fat, low-vegetable diet and 19% (P<0.01) in response to the low-fat, high-vegetable diet. Also, the Lp(a) concentration was increased by 7% (P<0.01) and 9% (P=0.01), respectively. CONCLUSIONS: Alterations in the dietary fat intake resulted in increased plasma concentrations of lipoprotein(a) and OxLDL-EO6.

Serum alpha-tocopherol concentrations and risk of type 1 diabetes mellitus: a cohort study in siblings of affected children.

Animal models have indicated that alpha-tocopherol may protect against type 1 diabetes mellitus (DM1). Epidemiological data on the subject are scarce. The objective of this study was to evaluate the association of serum alpha-tocopherol concentration and risk of DM1 in a cohort of initially non-diabetic siblings of children affected by DM1 (n = 722). We used two study designs: 1) Siblings who progressed to DM1 were compared with control siblings who remained negative for DM1-associated autoantibodies in a nested case-control study design. 2) All siblings with DM1-associated autoantibodies were prospectively followed for DM1. In both designs, high concentrations of serum alpha-tocopherol tended to be associated with a lower risk of DM1 (p = 0.08 and 0.09, respectively). Although the results did not reach statistical significance, they support the hypothesis that high alpha-tocopherol levels may protect against DM1.

Associations of dietary fiber with glucose metabolism in nondiabetic relatives of subjects with type 2 diabetes: the Botnia Dietary Study.

OBJECTIVE: To study cross-sectional associations of dietary fiber intake with insulin resistance, insulin secretion, and glucose tolerance in a population at high risk for type 2 diabetes. RESEARCH DESIGN AND METHODS: The subjects consisted of 248 male and 304 female adult nondiabetic relatives of patients with type 2 diabetes. Dietary intake was measured by means of two 3-day food records. Associations of total, water-insoluble, and water-soluble fiber with measures of glucose metabolism based on an oral glucose tolerance test, were analyzed by multiple linear regression analysis adjusting for sex, age, length of education, physical activity, BMI, waist-to-hip ratio, systolic blood pressure, and serum triglyceride and HDL cholesterol concentrations. The homeostasis model assessment insulin resistance index, the incremental 30-min serum insulin concentration divided by the incremental 30-min glucose concentration, and fasting and 2-h glucose concentrations were the outcome variables. RESULTS: The dietary intake of total as well as water-insoluble and water-soluble fiber was inversely associated with insulin resistance: -0.17 (0.07), P = 0.012; -0.15 (0.07), P = 0.024; and -0.14 (0.07), P = 0.049 [regression coefficients (SE)]. Fiber variables were unrelated to insulin secretion and plasma glucose concentrations. CONCLUSIONS: The results support evidence that a high intake of dietary fiber is associated with enhanced insulin sensitivity and therefore may have a role in the prevention of type 2 diabetes.

Effects of nationwide addition of selenium to fertilizers on foods, and animal and human health in Finland: From deficiency to optimal selenium status of the population.

Despite different geological features the Nordic countries are generally selenium-poor areas. In each country various factors such as food importation and life-style determine the selenium (Se) intake. Due to an extremely low Se intake in the 1970s in Finland, 0.025 mg/day, an official decision was made in 1984 to supplement multinutrient fertilizers with Se in the chemical form of sodium selenate. Almost all fertilizers used in Finland since 1985 have contained Se. Currently all crop fertilizers contain 15 mg Se/kg. Finland is still the only country to take this country-wide measure. In a national monitoring programme, sampling of cereals, basic foodstuffs, feeds, fertilizers, soils, and human tissues has been carried out annually since 1985 by four governmental research organizations. Sampling of foods has been done four times per year and human blood has been obtained annually from the same (n=60) adults. The accuracy of analyses has been verified by annual interlaboratory quality control. During this programme the selenium concentration of spring cereals has increased on average 15-fold compared with the level before the Se fertilization. The mean increase in the Se concentration in beef, pork and milk was 6-, 2- and 3-fold. In terms of Se, organically grown foods of plant origin are generally comparable to products produced before the Se supplementation of fertilizers. Milk from organically fed cows is 50% lower in Se than the usual milk. The average dietary human intake increased from 0.04 mg Se/day/10 MJ in 1985 to a present plateau of 0.08 mg Se/day/10 MJ, which is well above the current nutrition recommendations. Foods of animal origin contribute over 70% of the total daily Se intake. The mean human plasma Se concentration increased from 0.89 µmol/L to a general level of 1.40 µmol/L that can be considered to be an optimal status. The absence of Se deficiency diseases and a reference population have made conclusions on the impact on human health difficult. However, the rates of cardiovascular diseases and cancers have remained similar during the pre- and post-supplementation indicating medical and life-style factors to be much stronger determinants than Se. The nationwide supplementation of fertilizers with sodium selenate is shown to be effective and safe in increasing the Se intake of the whole population. Also, the health of animals has improved.

High intakes of vegetables, berries, and apples combined with a high intake of linoleic or oleic acid only slightly affect markers of lipid peroxidation and lipoprotein metabolism in healthy subjects.

BACKGROUND: A high consumption of vegetables and fruit is associated with decreased risk of ischemic heart disease and several cancers. The pathophysiology of these diseases involves free radical mechanisms. Diet may either enhance or diminish oxidative stress in the body. OBJECTIVE: We studied the effects of high and low intakes of vegetables, berries, and apples on markers of lipid peroxidation and lipoprotein metabolism in subjects consuming diets high in linoleic or oleic acid. DESIGN: For 6 wk, healthy men and women (n = 77; aged 19-52 y) consumed 1 of 4 controlled isoenergetic diets rich in either linoleic acid (11% of energy) or oleic acid (12% of energy) and containing either 815 or 170 g vegetables, berries, and apples/10 MJ. Nineteen healthy volunteers served as control subjects. Several markers of dietary compliance (plasma fatty acids, vitamin C, carotenoids, and quercetin), lipid peroxidation [ex vivo LDL oxidation, plasma and LDL thiobarbituric acid-reactive substances, paraoxonase (EC 3.1.8.1), and urinary 8-iso-prostaglandin F(2)(alpha)], and lipoprotein metabolism (plasma lipids, apolipoproteins, and lipid transfer protein activities) were measured from samples collected before and at the end of the experimental period. RESULTS: Plasma fatty acid composition and antioxidant concentrations showed that compliance with the diets was good. However, there were no significant differences between the diets in the markers of lipid peroxidation and lipoprotein metabolism. CONCLUSIONS: In healthy volunteers with adequate vitamin intakes, 6-wk diets differing markedly in the amounts of linoleic and oleic acid and vegetables, berries, and apples did not differ in their effects on lipid peroxidation or lipoprotein metabolism.

Betaine supplementation decreases plasma homocysteine concentrations but does not affect body weight, body composition, or resting energy expenditure in human subjects.

BACKGROUND: Betaine (trimethylglycine) is found in several tissues in humans. It is involved in homocysteine metabolism as an alternative methyl donor and is used in the treatment of homocystinuria in humans. In pigs, betaine decreases the amount of adipose tissue. OBJECTIVE: The aim of the study was to examine the effect of betaine supplementation on body weight, body composition, plasma homocysteine concentrations, blood pressure, and serum total and lipoprotein lipids. DESIGN: Forty-two obese, white subjects (14 men, 28 women) treated with a hypoenergetic diet were randomly assigned to a betaine-supplemented group (6 g/d) or a control group given placebo for 12 wk. The intervention period was preceded by a 4-wk run-in period with a euenergetic diet. RESULTS: Body weight, resting energy expenditure, and fat mass decreased significantly in both groups with no significant difference between the groups. Plasma homocysteine concentrations decreased in the betaine group ( +/- SD: 8.76 +/- 1.63 micro mol/L at 4 wk, 7.93 +/- 1.52 micro mol/L at 16 wk; P = 0.030 for the interaction of time and treatment). Diastolic blood pressure decreased without a significant difference between the groups. Serum total and LDL-cholesterol concentrations were higher in the betaine group than in the control group (P < 0.05). CONCLUSION: A hypoenergetic diet with betaine supplementation (6 g daily for 12 wk) decreased the plasma homocysteine concentration but did not affect body composition more than a hypoenergetic diet without betaine supplementation did.

Dietary intakes and plasma concentrations of carotenoids and tocopherols in relation to glucose metabolism in subjects at high risk of type 2 diabetes: the Botnia Dietary Study.

BACKGROUND: The role of antioxidants in the pathogenesis of type 2 diabetes is uncertain. OBJECTIVE: We evaluated cross-sectional relations of dietary intakes and plasma concentrations of antioxidants with glucose metabolism in a high-risk population. DESIGN: The subjects were 81 male and 101 female first- and second-degree, nondiabetic relatives of patients with type 2 diabetes. Antioxidant intake data were based on 3-d food records. Subjects taking supplements containing beta-carotene or alpha-tocopherol were excluded. Plasma antioxidant concentrations were measured by HPLC. By using multiple linear regression analysis and adjusting for demographic, anthropometric, and lifestyle covariates, we studied whether dietary and plasma alpha- and beta-carotene, lycopene, and alpha- and gamma-tocopherol were related to fasting and 2-h concentrations of glucose and nonesterified fatty acids during an oral-glucose-tolerance test, to the homeostasis model assessment index of insulin resistance, and to measures of beta cell function (incremental 30-min serum insulin concentration during an oral-glucose-tolerance test and first-phase insulin secretion during an intravenous-glucose-tolerance test). RESULTS: In men, dietary carotenoids were inversely associated with fasting plasma glucose concentrations (P < 0.05), plasma beta-carotene concentrations were inversely associated with insulin resistance (P = 0.003), and dietary lycopene was directly related to baseline serum concentrations of nonesterified fatty acids (P = 0.034). In women, dietary alpha-tocopherol and plasma beta-carotene concentrations were inversely and directly associated, respectively, with fasting plasma glucose concentrations (P < 0.05). In both sexes, cholesterol-adjusted alpha-tocopherol concentrations were directly associated with 2-h plasma glucose concentrations (P < 0.05). CONCLUSION: The data suggest an advantageous association of carotenoids, which are markers of fruit and vegetable intake, with glucose metabolism in men at high risk of type 2 diabetes.

Effects of equal weight loss with orlistat and placebo on body fat and serum fatty acid composition and insulin resistance in obese women.

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 x kg fat-free mass(-1) x min(-1)) and placebo (from 4.4 +/- 0.4 to 5.4 +/- 0.4 mg x kg fat-free mass(-1) x 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-gamma-linolenic acid (20:3n-6) 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.

Bioconversion of vaccenic acid to conjugated linoleic acid in humans.

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 < 0.001). 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.

Effect of alpha-linolenic acid-rich Camelina sativa oil on serum fatty acid composition and serum lipids in hypercholesterolemic subjects.

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 <.001) compared to the 2 other oil groups at the end of the study: 2.5 times higher compared to the rapeseed oil group and 4 times higher compared to the olive oil group. Respectively the proportions of 2 metabolites of alpha-linolenic acid (eicosapentaenoic and docosapentaenoic acids) increased and differed significantly in the camelina group from those in other groups. During the intervention, the serum low-density lipoprotein (LDL) cholesterol concentration decreased significantly by 12.2% in the camelina oil group, 5.4% in the rapeseed oil group, and 7.7% in the olive oil group. In conclusion, camelina oil significantly elevated the proportions of alpha-linolenic acid and its metabolites in serum of mildly or moderately hypercholesterolemic subjects. Camelina oil's serum cholesterol-lowering effect was comparable to that of rapeseed and olive oils.

Burnout patterns in rehabilitation: short-term changes in job conditions, personal resources, and health.

This longitudinal study reports the patterning of the burnout symptoms and the changes in employees' job conditions, personal resources, and psychological health 4 months after a rehabilitation intervention. The data were gathered by means of questionnaires before and after a rehabilitation period. Four patterns were identified: not burned out (n = 55), exhausted and cynical (n = 36), burned out (n = 26), and low professional efficacy (n = 18). These patterns differed in terms of job resources, personal resources, and depression. There were both positive and negative changes detected in participants' psychological health and job resources at the follow-up. The study shows the importance of identifying different burnout patterns in order to focus rehabilitation activities more effectively.