Tarja Nurmi

Process-induced changes on bioactive compounds in whole grain rye.

Manufacturing of healthy wholegrain foods demands knowledge of process-induced changes in macro-, micro- and non-nutrients. The high content of dietary fibre is a challenge in relation to good product texture and sensory quality. The stability and bioavailability of bioactive compounds have a marked influence on the health effects of cereal foods. It was confirmed that sterols, folates, tocopherols and tocotrienols, alkylresorcinols, lignans, phenolic acids and total phenolics are concentrated in the bran layers of the rye grain, and are only present at low levels in the flour endosperm. The levels of folate and easily-extractable phenolic compounds increase in germination and sourdough baking, but there are negligible changes in the levels of sterols, lignans and alk(en)ylresorcinols. The levels of tocopherols and tocotrienols are reduced during the sourdough fermentation. In conclusion, many of the bioactive compounds in wholegrain rye are stable during food processing, and their levels can even be increased with suitable processing.

Flavonoid intake and the risk of ischaemic stroke and CVD mortality in middle-aged Finnish men: the Kuopio Ischaemic Heart Disease Risk Factor Study

The role of flavonoids in CVD, especially in strokes, is unclear. Our aim was to study the role of flavonoids in CVD. We studied the association between the intakes of five subclasses (flavonols, flavones, flavanones, flavan-3-ols and anthocyanidins), a total of twenty-six flavonoids, on the risk of ischaemic stroke and CVD mortality. The study population consisted of 1950 eastern Finnish men aged 42-60 years free of prior CHD or stroke as part of the prospective population-based Kuopio Ischaemic Heart Disease Risk Factor Study. During an average follow-up time of 15.2 years, 102 ischaemic strokes and 153 CVD deaths occurred. In the Cox proportional hazards model adjusted for age and examination years, BMI,systolic blood pressure, hypertension medication, serum HDL- and LDL-cholesterol, serum TAG, maximal oxygen uptake, smoking, family history of CVD, diabetes, alcohol intake, energy-adjusted intake of folate, vitamin E, total fat and saturated fat intake (percentage of energy), men in the highest quartile of flavonol and flavan-3-ol intakes had a relative risk of 0.55 (95% CI 0.31, 0.99) and 0.59 (95% CI 0.30, 1.14) for ischaemic stroke, respectively, as compared with the lowest quartile. After multivariate adjustment, the relative risk for CVD death in the highest quartile of flavanone and flavone intakes were 0.54 (95% CI 0.32, 0.92) and 0.65 (95% CI 0.40, 1.05), respectively. The present results suggest that high intakes of flavonoids may be associated with decreased risk of ischaemic stroke and possibly with reduced CVD mortality.

Phyto-oestrogen database of foods and average intake in Finland

Information on phyto-oestrogen intake in various populations has been scanty until now, primarily because data on the content of these compounds in foods were lacking. We report here on expansion of the Finnish National Food Composition Database (Fineli) with values for the plant lignans matairesinol and secoisolariciresinol and the isoflavones daidzein and genistein. The values, expressed as aglycones, were based on food analyses (mainly GC-MS) or imputed from analytical data for 180 foods for lignans and 160 foods for isoflavones; additionally, over 1000 values were derived from the recipe database of Fineli. Average intake of these phyto-oestrogens was calculated using food consumption data of the National Dietary Survey FINDIET 1997, which was carried out in a random sample of the adult population in five areas in Finland. The dietary data were collected by 24 h recall =2862). The mean lignan intake was 434 (standard deviation (SD) 1575) microg/d and the mean isoflavone intake was 788 (SD 673) microg/d. Women had a higher lignan density (microg lignans/MJ) in their diet than men (P<0.05). Men had a higher mean daily isoflavone intake, 902 (SD 368) microg, than women, 668 (SD 963) microg (P<0.05). The sources of lignans were many: seeds, cereals, fruit, berries and vegetables. The main sources of isoflavones appeared to be processed meat products/sausages containing soya as an ingredient, and legumes as such. The average intake of lignans and isoflavones in Finland seems to be low, but intake varies throughout the population.

Metabolism of berry anthocyanins to phenolic acids in humans.

We studied the metabolism of berry anthocyanins to phenolic acids in six human subjects by giving them bilberry-lingonberry puree with and without oat cereals. Puree + cereals contained 1435 micromol of anthocyanins and 339 micromol of phenolic acids. The urinary excretion of measured 18 phenolic acids increased 241 micromol during the 48 h follow-up after the puree + cereals supplementation. The excretion peak of dietary phenolic acids was observed at 4-6 h after the puree + cereals supplementation and 2 h earlier after the supplementation of the puree alone. Homovanillic and vanillic acids were the most abundant metabolites, and they were partly produced from anthocyanins. No gallic acid, a fragmentation product of delphinidin glycosides, was detected, and only a very low amount of malvidin glycosides was possibly metabolized to syringic acid. Although anthocyanins were partly fragmented to phenolic acids, still a large part of metabolites remained unknown.

Isoflavone content of the soy based supplements

A large number of soy isoflavone products with indications of possible health effects are available on the market. Fifteen different soy based products were analyzed using high performance liquid chromatography (HPLC) with coulometric electrode array detector to determine the total amount of isoflavones in aglycones after the hydrolysis and identify the different forms of the isoflavone conjugates. The aim of the study was to evaluate how well the isoflavone content data supplied by the producers correspond to our analysis results. Only one product contained isoflavones measured in aglycones the same amount as was the value given by the producer. The total amount of the isoflavones in aglycones ranged from 0.121 to 201 mg/g. Measured amounts of isoflavones in aglycones after the hydrolysis were in general lower than the values in the product labels. Product data were often confusing and the concrete amount of isoflavones was difficult to find out.

Elevated Circulating LDL Phenol Levels in Men Who Consumed Virgin Rather Than Refined Olive Oil Are Associated with Less Oxidation of Plasma LDL

In human LDL, the bioactivity of olive oil phenols is determined by the in vivo disposition of the biological metabolites of these compounds. Here, we examined how the ingestion of 2 similar olive oils affected the content of the metabolic forms of olive oil phenols in LDL in men. The oils differed in phenol concentrations as follows: high (629 mg/L) for virgin olive oil (VOO) and null (0 mg/L) for refined olive oil (ROO). The study population consisted of a subsample from the EUROLIVE study and a randomized controlled, crossover design was used. Intervention periods lasted 3 wk and were preceded by a 2-wk washout period. The levels of LDL hydroxytyrosol monosulfate and homovanillic acid sulfate, but not of tyrosol sulfate, increased after VOO ingestion (P < 0.05), whereas the concentrations of circulating oxidation markers, including oxidized LDL (oxLDL), conjugated dienes, and hydroxy fatty acids, decreased (P < 0.05). The levels of LDL phenols and oxidation markers were not affected by ROO consumption. The relative increase in the 3 LDL phenols was greater when men consumed VOO than when they consumed ROO (P < 0.05), as was the relative decrease in plasma oxLDL (P = 0.001) and hydroxy fatty acids (P < 0.001). Plasma oxLDL concentrations were negatively correlated with the LDL phenol levels (r = -0.296; P = 0.013). Phenols in LDL were not associated with other oxidation markers. In summary, the phenol concentration of olive oil modulates the phenolic metabolite content in LDL after sustained, daily consumption. The inverse relationship of these metabolites with the degree of LDL oxidation supports the in vivo antioxidant role of olive oil phenolics compounds.

Intake of flavonoids and risk of cancer in Finnish men: The Kuopio Ischaemic Heart Disease Risk Factor Study

Limited amount of evidence suggests that high intake of flavonoids could be associated with decreased risk of lung and colorectal cancer, but more studies are needed. In this prospective cohort study, we assessed the relation between the intakes of 26 flavonoids from 5 subclasses; flavonols, flavones, flavanones, flavan‐3‐ols and anthocyanidins, and the risk of lung, prostate and colorectal cancer. The study population consisted of 2,590 middle‐aged eastern Finnish men of the prospective population‐based Kuopio Ischaemic Heart Disease Risk Factor (KIHD) Study. The mean intake of flavonoids was 131.0 ± 214.7 mg/day. During the mean follow‐up time of 16.2 years, 62 lung, 138 prostate, and 55 colorectal cancers occurred. All lung cancer cases occurred among either current smokers (n = 50) or previous smokers (n = 12). After adjustment for age, examination years, body mass index, smoking status, pack‐years of smoking, physical activity and intakes of alcohol, total fat, saturated fat, fiber, vitamin C and E, relative risk (RR) for lung cancer was 0.27 (95% CI: 0.11–0.66) for the highest quarter of total flavonoid intake as compared with the lowest quarter. Out of 5 flavonoid subclasses, flavonols and flavan‐3‐ols were associated with lung cancer, for the highest quarter of intake the RR were 0.29 (95% CI: 0.11–0.78) and 0.24 (95% CI: 0.09–0.64), respectively. No association between flavonoid intake and risk of prostate or colorectal cancer were found. We conclude that high intake of flavonoids is associated with decreased risk of lung cancer in middle‐aged Finnish smoking men.

Intake of fruit, berries, and vegetables and risk of type 2 diabetes in Finnish men: the Kuopio Ischaemic Heart Disease Risk Factor Study

BACKGROUND Although higher intakes of fruit, berries, and vegetables (FBV) have been associated with reduced risk of type 2 diabetes (T2D) in some observational studies, the evidence is limited and inconclusive. OBJECTIVE We assessed the relation of FBV intake and T2D incidence in Finnish men. DESIGN We studied 2332 men from the prospective, population-based Kuopio Ischaemic Heart Disease Risk Factor Study who were aged 42-60 y and free of T2D or impaired fasting glucose at baseline in 1984-1989. Food intake was assessed with 4-d food recording. T2D was assessed by using self-administered questionnaires, a fasting blood glucose measurement, a 2-h oral-glucose-tolerance test, and record linkage to a reimbursement register on diabetes medication expenses. In the Cox proportional hazards model, HRs for T2D were computed for the highest compared with lowest quartiles of FBV intake adjusted for age, examination year, body mass index, waist-to-hip ratio, smoking, education, physical activity, family history of diabetes, and energy and alcohol intakes. RESULTS During the mean follow-up time of 19.3 y, 432 new cases of T2D occurred. For the total FBV intake (with the exclusion of potatoes and fruit and berry juices), the extreme-quartile multivariable-adjusted HR for T2D was 0.76 (95% CI: 0.57, 1.02; P-trend = 0.15). In the analysis for FBV components, berries had a corresponding HR of 0.65 (95% CI: 0.49, 0.88; P-trend = 0.003), whereas no significant associations were shown for fruit, fruit and berry juices, and vegetables. CONCLUSION Fruit and vegetables, particularly berries, may reduce risk of T2D in men.

Simultaneous measurement of retinol, α-tocopherol and six carotenoids in human plasma by using an isocratic reversed-phase HPLC method

A simple and sensitive isocratic reversed-phase high-performance liquid chromatography (HPLC) method for simultaneous determination of retinol, alpha-tocopherol and six carotenoids in human plasma was described. Sample preparation of the earlier published method was further developed by addition of ultrapure water, which enabled aqueous layer to freeze facilitating phase separation without pipetting thus also improving precision of the method. Developed method appeared to be less laborious and time consuming compared to the traditional extraction methods, which require removal of organic layer by pipetting. The recoveries (absolute and relative) were between 80% and 103%. The intra-assay CVs were 1.1-4.0% (normal level) and 3.3-9.0% (low level). Inter-assay CVs were 5.3-8.8%. Reference method for all these analytes was not available, but a comparison with another published method was carried out. The results of the comparison matched satisfactorily. The method is used routinely in our laboratory in a large population-based study.

Lignans in selected wines

Wines have been studied a lot and several different groups of phenolic compounds have been analysed in wine samples, but lignans in wines have been only preliminary studied. In this study, we analysed 10 different wines of which eight were red wines and two white wines. Samples were selected among the most consumed wines in Finland in year 1999. Eight different lignans were analysed with HPLC using coulometric electrode array detector. The amount of lignans in red wines ranged from 0.812 to 1.406 mg/l. The main lignan in all studied wines was isolariciresinol and percentage amount of mammalian lignan precursors varied from 34 to 43% in the red wines. The amount of lignans was much lower in the studied white wines compared with the red wines.