The effect of a lignan complex isolated from flaxseed on inflammation markers in healthy postmenopausal women.

BACKGROUND AND AIM: Plant lignans are metabolised by the colonic micro-flora to the mammalian lignans enterodiol and enterolactone, which are hypothesized to be cardioprotective. The aim of this study was to investigate the effects of a plant lignan complex isolated from flaxseed, providing 500 mg/d of secoisolariciresinol diglucoside, on inflammatory markers. METHODS AND RESULTS: Healthy postmenopausal women (n=22) completed a randomised double-blind, placebo-controlled crossover study. Women consumed daily a low-fat muffin, with or without a lignan complex, for 6 weeks, separated by a 6-week washout period. A significant difference of approximately 15% (P=0.028) was observed for C-reactive protein (CRP) concentration between the lignan complex intervention period and placebo period. CRP concentrations (median; 25th, 75th percentiles) were 0.88 (0.63, 2.05) mg/L at baseline and 0.92 (0.59, 1.49) mg/L after the lignan complex intervention period compared with 0.80 (0.62, 1.62) mg/L at baseline and 1.10 (0.72, 1.62) mg/L after placebo. No significant differences in interleukin-6, tumor necrosis factor-alpha, soluble intracellular adhesion molecule-1, soluble vascular cell adhesion molecule-1, and monocyte chemoattractant protein-1 were found between the lignan complex intervention period and placebo period. CONCLUSION: Daily consumption for 6 week of a low-fat muffin enriched with a lignan complex may reduce CRP concentrations compared to a low-fat muffin with no lignans added.

Soya isoflavone-enriched cereal bars affect markers of endothelial function in postmenopausal women.

Soya isoflavones are thought to be cardioprotective due to their structural similarity to oestrogen. In order to investigate the effect of soya isoflavones on markers of endothelial function we conducted a randomised, double-blind, placebo-controlled, cross-over study with thirty healthy postmenopausal women. The women consumed cereal bars, with or without soya isoflavones (50 mg/d), for 8 weeks, separated by an 8-week washout period. Systemic arterial compliance (SAC), isobaric arterial compliance (IAC), flow-mediated endothelium-dependent vasodilation (FMD) and nitroglycerine-mediated endothelium-independent vasodilation (NMD) were measured at the beginning of the study and after each intervention period. Blood pressure (BP) and plasma concentrations of nitrite and nitrate (NOx) and endothelin-1 (ET-1) were measured at the beginning and end of each intervention period. NMD was 13.4 (SEM 2.0)% at baseline and 15.5 (SEM 1.1) % after isoflavone treatment compared with 12.4 (SEM 1.0)% after placebo treatment (P=0.03). NOx increased from 27.7 (SEM 2.7) to 31.1 (SEM 3.2) microM after isoflavones treatment compared with 25.4 (SEM 1.5) to 20.4 (SEM 1.1) microM after placebo treatment (P=0.003) and a significant increase in the NOx:ET-1 ratio (P=0.005) was observed after the isoflavone treatment compared with placebo. A significant difference in SAC after the isoflavone and placebo treatment was observed (P=0.04). No significant difference was found in FMD, IAC, BP and ET-1. In conclusion, 8 weeks' consumption of cereals bars enriched with 50 mg soya isoflavones/d increased plasma NOx concentrations and improved endothelium-independent vasodilation in healthy postmenopausal women.

The acceptability of isoflavones as a treatment of menopausal symptoms: a European survey among postmenopausal women.

OBJECTIVE: To investigate determinants of the acceptability of isoflavone products among postmenopausal women with regard to social and lifestyle factors, dietary habits, health concerns, food beliefs, menopausal symptoms and therapies, and to elucidate preferences for specific products. METHODS: A consumer survey was conducted among postmenopausal women in four European countries (Germany, Denmark, Italy and the UK), including a total of 465 respondents. RESULTS: The declared acceptability of isoflavones was highest in Germany (80%), followed by Italy (75%), the UK (59%) and Denmark (55%; p < 0.001). Among other factors, prior information about isoflavones (odds ratio (OR) 2.64, 95% confidence interval (CI) 1.54-4.51, p < 0.001) and belief that foods can be used to treat medical conditions (OR 2.18, 95% CI 1.17-4.05, p = 0.014) were the strongest predictors of potential acceptability. The preferred forms in which isoflavones might be taken differed markedly between countries. CONCLUSIONS: Information about the health effects of isoflavones and health-diet links should be considered the most important factors in attempts to influence the potential acceptability of isoflavone products. Foods enriched with isoflavones need to be developed with regard to specific cultural demands in order to assure consumer acceptance on the marketplace.

No effect of copper supplementation on biochemical markers of bone metabolism in healthy young adult females despite apparently improved copper status.

OBJECTIVE: To investigate the effects of increasing Cu intakes, above the usual dietary intake, on biomarkers of bone metabolism in healthy young adult females (aged 21-28 y) over a 4 week period. DESIGN: A double-blind, placebo-controlled randomised repeat crossover Cu supplementation trial. SETTING: The study was conducted at the Royal Veterinary and Agricultural University (RVAU), Copenhagen, Denmark. SUBJECTS: Sixteen healthy young adult females aged 20-28 y were recruited from among students at the RVAU. INTERVENTION: During the 4 week intervention periods in this randomised, crossover trial (3x4 weeks with a minimum 3 week wash-out period), each subject received, in addition to their usual diet, either 3 or 6 mg elemental Cu/day as CuSO4 or a matching placebo. On the last 3 days of each dietary period 24 h urines were collected. In addition, blood was collected on the last day of each dietary period. RESULTS: Serum Cu and erythrocyte superoxide dismutase (but not caeruloplasmin protein concentration or activity (putative indices of Cu status)) were significantly increased (P<0.05) after daily Cu supplementation with 3 and 6 mg/day for 4 weeks. Serum osteocalcin (biomarker of bone formation), urinary creatinine (Cr) concentration, urinary pyridinoline (Pyr)/Cr or deoxypyridinoline (Dpyr)/Cr excretion, or daily urinary Pyr or Dpyr excretion (biomarkers of bone resorption) were unaffected by Cu supplementation. CONCLUSION: Copper supplementation of the usual diet in healthy young adult females, while apparently improving Cu status, had no effect on biochemical markers of bone formation or bone resorption over 4 week periods. SPONSORSHIP: Funding from the European Commission.

Absorption and retention of selenium from shrimps in man.

This study was undertaken to evaluate the bioavailability of selenium in shrimps, a possible good source of selenium, by measurements of the absorption and retention of selenium and the effects on plasma selenium concentration and glutathione peroxidase activity. Twelve healthy young subjects (9F and 3M) received 100 g of shrimps each day for six weeks in addition to their habitual diet. In the third week of the study a balance period was inserted in which the subjects received all food from the department and collected faeces and urine over 5 days. Blood samples were collected at commencement of the study, after 2, 4, and 6 weeks. The selenium intake increased from 39.4 +/- 15.3 microg/d to 127 +/- 5.5 microg/d with the addition of shrimps. The apparent absorption of selenium from shrimps was 83 +/- 4%. Faecal and urinary selenium excretion was 32.5 +/- 17.0 microg/d and 21.2 +/- 9.0 microg/d, respectively and the total retention of selenium was 3.1 +/- 1.1 mg. Plasma selenium concentrations were 95.2 +/- 9.7 microg/L and 101.5 +/- 9.7 microg/L before and after six weeks of shrimp intake, respectively (p<0.05). Plasma and erythrocyte glutathione peroxidase activities were not influenced by shrimp intake. Thus, despite the high absorption and retention, plasma selenium concentrations were only moderately affected by an increase in selenium intake of about 100 microg/d in the chemical forms found in shrimp. Whether the accumulation of selenium from shrimps in tissues may represent a potential hazard is to be further investigated.

Copper supplementation in humans does not affect the susceptibility of low density lipoprotein to in vitro induced oxidation (FOODCUE project).

The oxidative modification of low-density lipoprotein cholesterol (LDL) has been implicated in the pathogenesis of atherosclerosis. Copper (Cu) is essential for antioxidant enzymes in vivo and animal studies show that Cu deficiency is accompanied by increased atherogenesis and LDL susceptibility to oxidation. Nevertheless, Cu has been proposed as a pro-oxidant in vivo and is routinely used to induce lipid peroxidation in vitro. Given the dual role of Cu as an in vivo antioxidant and an in vitro pro-oxidant, a multicenter European study (FOODCUE) was instigated to provide data on the biological effects of increased dietary Cu. Four centers, Northern Ireland (coordinator), England, Denmark, and France, using different experimental protocols, examined the effect of Cu supplementation (3 or 6 mg/d) on top of normal Cu dietary intakes or Cu-controlled diets (0.7/1.6/6.0 mg/d), on Cu-mediated and peroxynitrite-initiated LDL oxidation in apparently healthy volunteers. Each center coordinated its own supplementation regimen and all samples were subsequently transported to Northern Ireland where lipid peroxidation analysis was completed. The results from all centers showed that dietary Cu supplementation had no effect on Cu- or peroxynitrite-induced LDL susceptibility to oxidation. These data show that high intakes (up to 6 mg Cu) for extended periods do not promote LDL susceptibility to in vitro-induced oxidation.

Cholesterol-lowering potential in human subjects of fat from pigs fed rapeseed oil.

The possibility of achieving blood-lipid-lowering characteristics of pig fat by increasing the content of unsaturated fat in pig feed was evaluated. Three pig feeding regimens were applied: basal feed (no added fat or vitamin E), basal feed + rapeseed oil (60 g/kg feed), and basal feed + rapeseed oil (60 g/kg) + vitamin E (200 mg/kg). Meat and meat products from the three pig groups were incorporated into diets providing 86 g pig fat/10 MJ. The diets were served to twelve healthy human male subjects for 3 weeks each in a randomised crossover design. The diets prepared from pigs fed rapeseed oil had a lower content of saturated fatty acids (approximately 9 v. 11% of energy) and a higher content of polyunsaturated fatty acids (approximately 6 v. 4% of energy) than the diet prepared from pigs fed the basal feed. Diets based on fat from pigs fed the rapeseed oil resulted in significantly lower (approximately 4%, P = 0.019) total serum cholesterol concentration compared with the diet from pigs fed the basal feed. No differences were observed in LDL-, HDL- or VLDL-cholesterol, or in triacylglycerol or VLDL-triacylglycerol concentrations. Addition of vitamin E to the pig feed resulted in only a minor increase in vitamin E content in the human subjects' diet and the vitamin E content was low in all three pig diets. Plasma vitamin E concentration in the human subjects at the end of the period with diets from pigs fed rapeseed oil without vitamin E was significantly lower (P = 0.04) than in the other two diet periods. In conclusion, an increased content of rapeseed oil in pig feed changes the fatty acid composition of the pig fat in a way that has a potential to reduce blood cholesterol concentrations in human subjects. However, intake of pig fat with a higher content of unsaturated fatty acids needs to be matched by a higher dietary intake of vitamin E.