Dietary fat quality and serum androgen concentrations in middle-aged men.

BACKGROUND/OBJECTIVES: Average testosterone concentrations in men have declined over the last few decades. The reasons for this are not fully known, but changes in dietary fat quality have been suggested to have a role. This study aimed to investigate the associations of different dietary fatty acids with serum androgen concentrations. SUBJECTS/METHODS: A total of 2546 men with a mean age of 53 from the Kuopio Ischaemic Heart Disease Risk Factor Study were included in this cross-sectional study. Associations between dietary saturated (SFA), monounsaturated (MUFA), polyunsaturated (PUFA) and trans (TFA) fatty acids and concentrations of serum total and free testosterone and steroid hormone binding globulin (SHBG) were analyzed with analysis of covariance and linear regression analysis. Associations of isocaloric replacement of nutrients and androgen concentrations were analyzed with multivariate nutrient-density models. RESULTS: After adjustment for age, examination year and energy intake, higher SFA intake was associated with higher serum total and free testosterone and SHBG concentrations, and higher PUFA intake with lower concentrations. However, the associations were attenuated and not statistically significant after further adjustments for potential confounders. MUFA and TFA intakes were not associated with androgen concentrations. In isocaloric substitution models, replacing dietary protein with SFA was associated with higher serum total testosterone and SHBG concentrations. After excluding men with history of CVD or diabetes (n = 1021), no statistically significant associations were found. CONCLUSIONS: Dietary fat quality was not independently associated with serum androgen concentrations in middle-aged men. However, replacing protein with SFA may be associated with higher serum androgen concentrations.

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.

Molecular evaluation of vitamin D responsiveness of healthy young adults.

Vitamin D3 has via its metabolites 25-hydroxyvitamin D3 (25(OH)D3) and 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) direct effects on the transcriptome and the epigenome of most human cells. In the VitDbol study we exposed 35 healthy young adults to an oral vitamin D3 dose (2000µg) or placebo and took blood samples directly before the supplementation as well as at days 1, 2 and 30. Within 24h the vitamin D3 intake raised the average serum levels of both 25(OH)D3 and 1,25(OH)2D3 by approximately 20%. However, we observed large inter-individual differences in these serum levels, reflected by the average ratios between 25(OH)D3 and 1,25(OH)2D3 concentrations ranging from 277 to 1365. Interestingly, average serum parathyroid hormone (PTH) levels increased at day 1 by some 10% but then decreased within the following four weeks to levels 5% below baseline. In peripheral blood mononuclear cells (PBMCs) that were isolated at the same time points we determined vitamin D-modulated chromatin accessibility by FAIRE-qPCR at selected genomic loci. This method is well suited to evaluate both short-term and long-term in vivo effects of vitamin D on the epigenome of human subjects. The differential vitamin D responsiveness of the VitDbol study participants was determined via individual changes in their PTH levels or chromatin accessibility in relation to alterations in 25(OH)D3 concentrations. This led to the segregation of the subjects into 14 high, 11 mid and 10 low responders. In summary, the vitamin D responsiveness classification provides additional information compared to a vitamin D status assessment based on single 25(OH)D3 serum measurements. The study was registered at Clinicaltrials.gov (NCT02063334).

Glucose Metabolism Effects of Vitamin D in Prediabetes: The VitDmet Randomized Placebo-Controlled Supplementation Study.

Epidemiological evidence suggests a role for vitamin D in type 2 diabetes prevention. We investigated the effects of vitamin D3 supplementation on glucose metabolism and inflammation in subjects with prediabetes. A 5-month randomized, double-blind, placebo-controlled intervention with three arms (placebo, 40 µg/d, or 80 µg/d vitamin D3) was carried out among sixty-eight overweight (BMI 25-35) and aging (≥60 years) subjects from Finland, with serum 25-hydroxyvitamin D3 [25(OH)D3] < 75 nmol/L and either impaired fasting glucose or impaired glucose tolerance. Analyses included 66 subjects who completed the trial. Glucose metabolism was evaluated by fasting and 2-hour oral glucose tolerance test-derived indices and glycated hemoglobin. Inflammation was evaluated by high-sensitive C-reactive protein and five cytokines. Although a dose-dependent increase in serum 25(OH)D3 over the supplementation period was observed (P trend < 0.001), there were no other statistically significant differences in changes in the 13 glucose homeostasis indicators between the study groups other than increase in the 120 min glucose concentration (P trend = 0.021) and a decreasing trend both in 30 min plasma insulin (P trend = 0.030) and glycated hemoglobin (P trend = 0.024) concentrations. A borderline statistically significant decreasing trend in interleukin-1 receptor antagonist concentration was observed (P = 0.070). Vitamin D3 supplementation does not improve glucose metabolism in ageing subjects with prediabetes but may have modest anti-inflammatory effects.

Dietary fatty acids and risk of coronary heart disease in men: the Kuopio Ischemic Heart Disease Risk Factor Study.

OBJECTIVE: The epidemiological evidence of the role of dietary saturated fatty acids (SFA) in the development of coronary heart disease (CHD) is inconsistent. We investigated the associations of dietary fatty acids with the risk of CHD and carotid atherosclerosis in men with high SFA intake and high rates of CHD. APPROACH AND RESULTS: In total, 1981 men from the population-based Kuopio Ischemic Heart Disease Risk Factor Study (KIHD), aged 42 to 60 years and free of CHD at baseline in 1984 to 1989, were investigated. Food consumption was assessed with 4-day food recording. Multivariate nutrient-density models were used to analyze isocaloric replacement of nutrients. CHD events were ascertained from national registries. Carotid atherosclerosis was assessed by ultrasonography of the common carotid artery intima-media thickness in 1015 men. During the average follow-up of 21.4 years, 183 fatal and 382 nonfatal CHD events occurred. SFA or trans fat intakes were not associated with CHD risk. In contrast, monounsaturated fat intake was associated with increased risk and polyunsaturated fat intake with decreased risk of fatal CHD, whether replacing SFA, trans fat, or carbohydrates. The associations with carotid atherosclerosis were broadly similar, whereas the associations with nonfatal CHD were weaker. CONCLUSIONS: Our results suggest that SFA intake is not an independent risk factor for CHD, even in a population with higher ranges of SFA intake. In contrast, polyunsaturated fat intake was associated with lower risk of fatal CHD, whether replacing SFA, trans fat, or carbohydrates. Further investigation on the effect of monounsaturated fat on the CHD risk is warranted.

Serum omega-3 polyunsaturated fatty acids and risk of incident type 2 diabetes in men: the Kuopio Ischemic Heart Disease Risk Factor study.

OBJECTIVE The relationship between fish or omega-3 polyunsaturated fatty acids (PUFAs) and type 2 diabetes is inconclusive. Even contaminants in fish, such as mercury, may modify the effects. We investigated the associations between serum omega-3 PUFAs eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), docosahexaenoic acid (DHA), α-linolenic acid (ALA), hair mercury, and risk of incident type 2 diabetes in middle-aged and older Finnish men. RESEARCH DESIGN AND METHODS A total of 2,212 men from the prospective, population-based Kuopio Ischemic Heart Disease Risk Factor study, aged 42-60 years and free of type 2 diabetes at baseline in 1984-1989, were investigated. Serum PUFA and hair mercury were used as biomarkers for exposure. Dietary intakes were assessed with 4-day food recording. Type 2 diabetes was assessed by self-administered questionnaires and fasting and 2-h oral glucose tolerance test blood glucose measurement at re-examination rounds 4, 11, and 20 years after the baseline and by record linkage to hospital discharge registry and reimbursement register on diabetes medication expenses. Cox proportional hazards models were used to analyze associations. RESULTS During the average follow-up of 19.3 years, 422 men developed type 2 diabetes. Men in the highest versus the lowest serum EPA + DPA + DHA quartile had 33% lower multivariate-adjusted risk for type 2 diabetes (95% CI 13-49; P trend 0.01). No statistically significant associations were observed with serum or dietary ALA, dietary fish or EPA + DHA, or hair mercury. CONCLUSIONS Serum long-chain omega-3 PUFA concentration, an objective biomarker for fish intake, was associated with long-term lower risk of type 2 diabetes.

NMR protocol for determination of oxidation susceptibility of serum lipids and application of the protocol to a chocolate study.

A protocol for determination of oxidation susceptibility of serum lipids based on proton nuclear magnetic resonance ((1)H NMR) spectroscopy is presented and compared to the commonly used spectrophotometric method. Even though there are methodological differences between these two methods, the NMR-based oxidation susceptibility correlates well (r(2) = 0.73) with the lag time determined spectrophotometrically. In addition to the oxidizability of serum lipids, the NMR method provides also information about the lipid profile. The NMR oxidation assay was applied to the chocolate study including fasting serum samples (n = 45) from subjects who had consumed white (WC), dark (DC) or high-polyphenol chocolate (HPC) daily for 3 weeks. The oxidation susceptibility of serum lipids decreased in the HPC group, and there was a significant difference between the WC and HPC groups (P = 0.031). According to the random forest analysis, the consumption of the HPC chocolate induced changes to the amounts of HDL, phosphatidylcholine, sphingomyelin, and nervonic, docosahexaenoic and myristic acids. Furthermore, arachidonic, docosahexaenoic, docosapentaenoic and palmitic acids, gamma-glutamyl transferase, hemoglobin, HDL, phosphatidylcholine and choline containing phospholipids explained about 60% of the oxidation susceptibility values. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11306-011-0323-2) contains supplementary material, which is available to authorized users.

Dietary supplements and mortality rate in older women: the Iowa Women's Health Study.

BACKGROUND: Although dietary supplements are commonly taken to prevent chronic disease, the long-term health consequences of many compounds are unknown. METHODS: We assessed the use of vitamin and mineral supplements in relation to total mortality in 38,772 older women in the Iowa Women's Health Study; mean age was 61.6 years at baseline in 1986. Supplement use was self-reported in 1986, 1997, and 2004. Through December 31, 2008, a total of 15,594 deaths (40.2%) were identified through the State Health Registry of Iowa and the National Death Index. RESULTS: In multivariable adjusted proportional hazards regression models, the use of multivitamins (hazard ratio, 1.06; 95% CI, 1.02-1.10; absolute risk increase, 2.4%), vitamin B(6) (1.10; 1.01-1.21; 4.1%), folic acid (1.15; 1.00-1.32; 5.9%), iron (1.10; 1.03-1.17; 3.9%), magnesium (1.08; 1.01-1.15; 3.6%), zinc (1.08; 1.01-1.15; 3.0%), and copper (1.45; 1.20-1.75; 18.0%) were associated with increased risk of total mortality when compared with corresponding nonuse. Use of calcium was inversely related (hazard ratio, 0.91; 95% confidence interval, 0.88-0.94; absolute risk reduction, 3.8%). Findings for iron and calcium were replicated in separate, shorter-term analyses (10-year, 6-year, and 4-year follow-up), each with approximately 15% of the original participants having died, starting in 1986, 1997, and 2004. CONCLUSIONS: In older women, several commonly used dietary vitamin and mineral supplements may be associated with increased total mortality risk; this association is strongest with supplemental iron. In contrast to the findings of many studies, calcium is associated with decreased risk.

Association of serum 25-hydroxyvitamin D with the risk of death in a general older population in Finland.

PURPOSE: To investigate the association between serum 25-hydroxyvitamin D [25(OH)D] concentration, a marker of vitamin D status, and risk of all-cause and cardiovascular mortality in a general older population with relatively low average serum 25(OH)D concentrations. METHODS: The study population included 552 men and 584 women aged 53-73 years who were free of CVD and cancer at baseline in 1998-2001 from the prospective, population-based Kuopio Ischaemic Heart Disease Risk Factor (KIHD) Study. Deaths were ascertained by a computer linkage to the national cause of death register. All deaths that occurred from the study entry to December 31, 2008, were included. Cox proportional hazards regression models were used to analyze the association between serum 25(OH)D and risk of death. RESULTS: The mean serum 25(OH)D concentration was 43.7 nmol/L (SD 17.8), with a strong seasonal variation. During the average follow-up of 9.1 years, 87 participants died, 35 from cardiovascular disease (CVD). After multivariable-adjustments, the hazard ratios (HR) for all cause death in the tertiles of serum 25(OH)D were 1, 1.68 (95% CI: 0.92, 3.07) and 2.06 (95% CI: 1.12, 3.80), p for trend = 0.02. CONCLUSIONS: Our study supports the accumulating evidence from epidemiological studies that vitamin D deficiency is associated with increased risk of death. Large-scale primary prevention trials with vitamin D supplementation are warranted.

Coffee, tea and caffeine intake and the risk of severe depression in middle-aged Finnish men: the Kuopio Ischaemic Heart Disease Risk Factor Study.

OBJECTIVE: Only a few cross-sectional studies have assessed the association between coffee, tea and caffeine and the risk of depression. Our aim was to determine the association in a population-based cohort study. DESIGN: The population-based Kuopio Ischaemic Heart Disease Risk Factor Study cohort was recruited between 1984 and 1989 and followed until the end of 2006. We investigated the association between the intake of coffee, tea and caffeine and depression. SETTING: Eastern Finland. SUBJECTS: Middle-aged men (n 2232). RESULTS: Altogether, forty-nine men received a discharge diagnosis of depression. We classified subjects into quartiles according to their mean daily coffee intake: non-drinkers (n 82), light drinkers (<375 ml/d, n 517), moderate drinkers (375-813 ml/d, n 1243) and heavy drinkers (>813 ml/d, n 390). Heavy drinkers had a decreased risk (RR = 0.28, 95 % CI 0.08, 0.98) for depression when compared with non-drinkers, after adjustment for age and examination years. Further adjustment for socio-economic status, alcohol consumption, smoking, maximal oxygen uptake, BMI and the energy-adjusted daily intakes of folate and PUFA did not attenuate this association (relative risk (RR) = 0.23, 95 % CI 0.06, 0.83). No associations were observed between depression and intake of tea (drinkers v. non-drinkers; RR = 1.19, 95 % CI 0.54, 2.23) or caffeine (highest quartile v. lowest quartile; RR = 0.99, 95 % CI 0.40, 2.45). CONCLUSIONS: Coffee consumption may decrease the risk of depression, whereas no association was found for tea and caffeine intake.

Dietary intake and urinary excretion of lignans in Finnish men.

Intake of lignans has been assessed in different study populations, but so far none of the studies has compared the daily intake of lignans and the urinary excretion of plant and enterolignans. We assessed the intake of lariciresinol, pinoresinol, secoisolariciresinol and matairesinol in 100 Finnish men consuming their habitual omnivorous diet, and measured the 24 h urinary excretion of plant and enterolignans to compare the intake and metabolism. Dietary determinants of lignan intake and their urinary excretion were also determined. The mean intake of lignans was 1224 (sd 539) mug/d, of which lariciresinol and pinoresinol covered 78 %. Almost half (47 %) of the intake of lignans was explained by the intake of rye products, berries, coffee, tea and roots. The urinary excretion of plant lignans corresponded to 17 % and enterolignans to 92 % of the intake of lignans. The urinary excretion of plant lignans was explained 14 % by the intake of rye products and intake of coffee, and consequently 3-7 % by the intake of water-insoluble fibre. The urinary excretion of enterolactone was explained 11 % by the intake of vegetables and rye products, 14 % by the intake of water-soluble fibre and only 4 % by the intake of lariciresinol. Although the assessed intake of lignans corresponded well with the urinary excretion of lignans, the enterolactone production in the human body depended more on the dietary sources of lignans than the absolute intake of lignans.

Serum long-chain n-3 polyunsaturated fatty acids and risk of hospital diagnosis of atrial fibrillation in men.

BACKGROUND: Atrial fibrillation (AF) is a common cardiac arrhythmia. Regular fish consumption has been shown to reduce the risk of AF in some but not all studies. Long-chain n-3 polyunsaturated fatty acids (PUFAs) from fish have been suggested to account for these beneficial effects. We tested this hypothesis by studying the association between the serum long-chain n-3 PUFAs eicosapentaenoic acid, docosapentaenoic acid, and docosahexaenoic acid and risk of AF in men. METHODS AND RESULTS: A total of 2174 men from the prospective population-based Kuopio Ischemic Heart Disease Risk Factor Study, 42 to 60 years old and free of AF at baseline in 1984 to 1989, were studied. During the average follow-up time of 17.7 years, 240 AF events occurred. In the Cox proportional hazards model, the multivariable-adjusted hazard ratio in the highest (>5.33%) versus the lowest (<3.61%) quartile of eicosapentaenoic acid plus docosapentaenoic acid plus docosahexaenoic acid was 0.65 (95% confidence interval 0.44 to 0.96, P for trend=0.07). Evaluated individually, only serum docosahexaenoic acid was associated with the risk of AF (hazard ratio in the highest versus the lowest quartile 0.62, 95% confidence interval 0.42 to 0.92, P for trend=0.02). Exclusion of subjects (n=233) with myocardial infarction or congestive heart failure either at baseline or that preceded the AF event during follow-up slightly strengthened the associations. Serum intermediate chain-length n-3 PUFA, alpha-linolenic acid, or hair methylmercury concentration were not associated with the risk. CONCLUSIONS: An increased concentration of long-chain n-3 PUFAs in serum, a marker of fish or fish oil consumption, may protect against AF. Serum docosahexaenoic acid concentration had the greatest impact.

Changes in LDL fatty acid composition as a response to olive oil treatment are inversely related to lipid oxidative damage: The EUROLIVE study.

OBJECTIVE: The aim of our study was to assess the changes in the fatty acid composition of low density lipoproteins (LDL) after sustained consumption of olive oil at real-life doses (25 mL/day) and their relationship with lipid oxidative damage. METHODS: A multi-center randomized, cross-over, clinical trial with 3 similar types of olive oils, but with differences in the phenolic content, was conducted on 200 healthy European subjects. Intervention periods were of 3 weeks separated by 2-week washout periods. The LDL fatty acid content was measured in samples drawn at baseline and after the last intervention period. RESULTS: After olive oil ingestion oleic acid concentration in LDL increased (1.9%; p < 0.001) and those of linoleic (1.1%; p < 0.002) and arachidonic acid (0.5%; p < 0.001) decreased. Monounsaturated/polyunsaturated fatty acid and oleic/linoleic acid ratios in LDL increased after olive oil consumption. An inverse relationship between the oleic/linoleic acid ratio and biomarkers of oxidative stress was observed. One unit increase in the oleic/linoleic acid ratio was associated with a decrease of 4.2 microg/L in plasma isoprostanes. CONCLUSION: Consumption of olive oil at real-life doses improved the fatty acid profile in LDL, the changes being associated with a reduction of the oxidative damage to lipids.

Effect of olive oils on biomarkers of oxidative DNA stress in Northern and Southern Europeans.

High consumption of olive oil in the Mediterranean diet has been suggested to protect DNA against oxidative damage and to reduce cancer incidence. We investigated the impact of the phenolic compounds in olive oil, and the oil proper, on DNA and RNA oxidation in North, Central, and South European populations. In a multicenter, double-blind, randomized, controlled crossover intervention trial, the effect of olive oil phenolic content on urinary oxidation products of guanine (8-oxo-guanine, 8-oxo-guanosine and 8-oxo-deoxyguanosine) was investigated. Twenty-five milliliters of three olive oils with low, medium, and high phenolic content were administered to healthy males (n=182) daily for 3 wk. At study baseline the urinary excretion of 8-oxo-guanosine (RNA oxidation) and 8-oxo-deoxyguanosine (DNA oxidation) was higher in the Northern regions of Europe compared with Central and Southern European regions (P=0.035). Urinary excretion of the 8 hydroxylated forms of guanine, guanosine, deoxyguanosine and their nonoxidized forms were not different when comparing olive oils with low, medium, and high phenolic content given for 2 wk. Testing the effect of oil from urinary 8-oxo-deoxyguanosine changes from baseline to post-treatment showed a reduction of DNA oxidation by 13% (P=0.008). These findings support the idea that ingestion of olive oil is beneficial and can reduce the rate of oxidation of DNA. This effect is not due to the phenolic content in the olive oil. The higher DNA and RNA oxidation in Northern European regions compared with that in Central and Southern regions supports the contention that olive oil consumption may explain some of the North-South differences in cancer incidences in Europe.

The effect of polyphenols in olive oil on heart disease risk factors: a randomized trial.

BACKGROUND: Virgin olive oils are richer in phenolic content than refined olive oil. Small, randomized, crossover, controlled trials on the antioxidant effect of phenolic compounds from real-life daily doses of olive oil in humans have yielded conflicting results. Little information is available on the effect of the phenolic compounds of olive oil on plasma lipid levels. No international study with a large sample size has been done. OBJECTIVE: To evaluate whether the phenolic content of olive oil further benefits plasma lipid levels and lipid oxidative damage compared with monounsaturated acid content. DESIGN: Randomized, crossover, controlled trial. SETTING: 6 research centers from 5 European countries. PARTICIPANTS: 200 healthy male volunteers. MEASUREMENTS: Glucose levels, plasma lipid levels, oxidative damage to lipid levels, and endogenous and exogenous antioxidants at baseline and before and after each intervention. INTERVENTION: In a crossover study, participants were randomly assigned to 3 sequences of daily administration of 25 mL of 3 olive oils. Olive oils had low (2.7 mg/kg of olive oil), medium (164 mg/kg), or high (366 mg/kg) phenolic content but were otherwise similar. Intervention periods were 3 weeks preceded by 2-week washout periods. RESULTS: A linear increase in high-density lipoprotein (HDL) cholesterol levels was observed for low-, medium-, and high-polyphenol olive oil: mean change, 0.025 mmol/L (95% CI, 0.003 to 0.05 mmol/L), 0.032 mmol/L (CI, 0.005 to 0.05 mmol/L), and 0.045 mmol/L (CI, 0.02 to 0.06 mmol/L), respectively. Total cholesterol-HDL cholesterol ratio decreased linearly with the phenolic content of the olive oil. Triglyceride levels decreased by an average of 0.05 mmol/L for all olive oils. Oxidative stress markers decreased linearly with increasing phenolic content. Mean changes for oxidized low-density lipoprotein levels were 1.21 U/L (CI, -0.8 to 3.6 U/L), -1.48 U/L (-3.6 to 0.6 U/L), and -3.21 U/L (-5.1 to -0.8 U/L) for the low-, medium-, and high-polyphenol olive oil, respectively. LIMITATIONS: The olive oil may have interacted with other dietary components, participants' dietary intake was self-reported, and the intervention periods were short. CONCLUSIONS: Olive oil is more than a monounsaturated fat. Its phenolic content can also provide benefits for plasma lipid levels and oxidative damage. International Standard Randomised Controlled Trial number: ISRCTN09220811.

Ingestion of oregano extract increases excretion of urinary phenolic metabolites in humans.

Despite the promising antioxidant action of Lamiaceae herbs in vitro, human studies on these potential sources of dietary antioxidants have remained scarce. In this work, the phenolic acids recovered in human urine after single ingestion of Origanum onites extract were analyzed. The excretion was increased 4- and 2-fold during 0-24 and 24-48 h of the follow-up, respectively. The mean increase in the excretion of phenolic compounds exceeded the ingested amount of identified phenolic acids. The result can be partly explained by rosmarinic acid, the main identified phenolic constituent in the extract, as well as flavonoids present in minor amounts, presumably being metabolized into a double amount of simple phenolic metabolites. Furthermore, unidentified phenolic constituents in the extract partly contribute to the excretory increase. The main metabolite, p-hydroxybenzoic acid, was excreted rapidly. The results show that constituents of oregano extract and, in particular, their metabolites may contribute to the dietary intake of phenolic antioxidants.

Consumption of juice fortified with oregano extract markedly increases excretion of phenolic acids but lacks short- and long-term effects on lipid peroxidation in healthy nonsmoking men.

Oregano has been shown to possess antioxidant capacity in various in vitro models and has thus been suggested to be potentially beneficial to human health, but studies in humans are lacking. The aim of this study was to investigate the bioavailability and the effects of Origanum vulgare extract supplementation on serum lipids and lipid peroxidation in healthy nonsmoking men. A four-week double-blinded supplementation trial was concluded in which volunteers (n = 45) were randomized to consume daily mango-orange juice (placebo), mango-orange juice enriched with 300 mg/d total phenolic compounds from oregano extract, or mango-orange juice enriched with 600 mg/d total phenolic compounds from oregano extract. The excretion of phenolic compounds was markedly increased in the higher phenolic group as compared to the placebo group, but no significant changes were observed in the safety parameters, serum lipids, or biomarkers of lipid peroxidation.

Carotenoids and cardiovascular health.

Cardiovascular disease (CVD) is the main cause of death in Western countries. Nutrition has a significant role in the prevention of many chronic diseases such as CVD, cancers, and degenerative brain diseases. The major risk and protective factors in the diet are well recognized, but interesting new candidates continue to appear. It is well known that a greater intake of fruit and vegetables can help prevent heart diseases and mortality. Because fruit, berries, and vegetables are chemically complex foods, it is difficult to pinpoint any single nutrient that contributes the most to the cardioprotective effects. Several potential components that are found in fruit, berries, and vegetables are probably involved in the protective effects against CVD. Potential beneficial substances include antioxidant vitamins, folate, fiber, and potassium. Antioxidant compounds found in fruit and vegetables, such as vitamin C, carotenoids, and flavonoids, may influence the risk of CVD by preventing the oxidation of cholesterol in arteries. In this review, the role of main dietary carotenoids, ie, lycopene, beta-carotene, alpha-carotene, beta-cryptoxanthin, lutein, and zeaxanthin, in the prevention of heart diseases is discussed. Although it is clear that a higher intake of fruit and vegetables can help prevent the morbidity and mortality associated with heart diseases, more information is needed to ascertain the association between the intake of single nutrients, such as carotenoids, and the risk of CVD. Currently, the consumption of carotenoids in pharmaceutical forms for the treatment or prevention of heart diseases cannot be recommended.

Polyphenol-rich phloem enhances the resistance of total serum lipids to oxidation in men.

In humans, polyphenol supplementation studies have resulted in inconsistent findings in lipid peroxidation. Our aim was to investigate the effects of a 4-week consumption of polyphenol-rich phloem on serum lipids and lipid peroxidation in the hydrophilic fraction of serum and on isolated lipoproteins. We conducted a randomized double-blind supplementation study consisting of 75 nonsmoking hypercholesterolemic men. Participants consumed 70 g daily of either rye bread (placebo) or phloem-fortified rye bread containing 31 mg (low polyphenol, LP) or 62 mg (high polyphenol, HP) of catechins. The ex vivo susceptibility of total serum lipids and VLDL and LDL to oxidation after copper induction was measured as a lag time to the maximal oxidation rate at the baseline and after the supplementation. In the HP group, an increase in the oxidation resistance of total serum lipids was observed (11.4%), while no effect was seen in the LP group (-0.8%) or in the placebo group (-1.0%) (p = 0.007). No differences were observed in the oxidation resistance of VLDL and LDL between the study groups. The phloem also increased in vitro oxidation resistance of serum lipids and radical scavenging activity (DPPH.) in a dose-dependent manner. Our results suggest that polyphenols may inhibit lipid peroxidation in the hydrophilic fraction of serum.