Dietary sources and sociodemographic and economic factors affecting vitamin D and calcium intakes in Flemish preschoolers.

BACKGROUND/OBJECTIVES: Low calcium and vitamin D intakes have been associated with health risks in childhood and adulthood. This study aims to investigate dietary sources of calcium and vitamin D intake, and its associated sociodemographic, economic and lifestyle factors among preschoolers. SUBJECTS/METHODS: Three-day estimated diet records from 696 Flemish preschoolers 2.5-6.5 years old (51% boys) were used (66% of 1052 collected diaries). Contribution of 58 food groups to calcium and vitamin D intake were computed. Multiple linear regression was used to examine associations of intakes with sociodemographic, economic and lifestyle factors. RESULTS: Mean calcium intake (844 mg per day) was above, and mean vitamin D intake (2.0 µg per day) largely below the Belgian recommendations. Milk, sweetened milk drinks and cheese were the main sources of calcium intakes (26, 25 and 11%, respectively). Butter and margarine were the main vitamin D sources (26%), followed by growth milk (=fortified milk) (20%) and fish (15%). Calcium and vitamin D intake were negatively associated with participants' age, and calcium positively with parental education and family size. The child's gender, supplement use and physical activity level, and the employment status and smoking behaviour of the parents were not associated with calcium or vitamin D intake. CONCLUSIONS: Flemish preschoolers had too low vitamin D intakes while most had adequate calcium intakes. Milk (including sweetened, fortified/growth milk) was the main food source of calcium intake and the second important source of vitamin D intake after butter and margarine. Calcium intake was positively associated with parental education, while vitamin D intake was not.

Variation in intakes of calcium, phosphorus, magnesium, iron and potassium in 10 countries in the European Prospective Investigation into Cancer and Nutrition study.

BACKGROUND/OBJECTIVES: Adequate mineral intake is important for the maintenance of bone health, cellular function and general metabolism, and possibly in the aetiology of cancer and other chronic diseases. This study aimed at investigating variation in intakes of selected minerals across 10 European countries participating in the EPIC (European Prospective Investigation into Cancer and Nutrition) study. METHODS: Nutrient intakes for 36 034 subjects, aged between 35 and 74 years, in 27 centres were obtained using standardized 24-h dietary recall software (EPIC-SOFT). Mean intakes of calcium, phosphorus, magnesium, iron and potassium were calculated by centre and weighted by season and day of the week and were also stratified by age group. The contribution of food groups to total nutrient intake was calculated. RESULTS: There was clear geographical variability in intakes, with differences ranging from 35% for magnesium to 90% for iron in men and 36% for potassium to 75% for calcium in women, and a twofold difference in sources of haem iron (meat and fish). There was a geographical gradient in iron intake, with higher intakes in Southern than in Northern Europe and also around a twofold north-south gradient in the contribution of fruits and vegetables to potassium intake. Compared with reference intakes, the majority of age groups and centres had intakes above the recommended levels. Dairy foods and products contributed the most to calcium and phosphorus intake in almost all centres. Cereals and cereal products contributed the most to magnesium and iron intakes, except in Greece and Germany. CONCLUSIONS: Intakes of minerals vary substantially throughout Europe, with some geographical variability in their food sources.

Plasma phyto-oestrogens and prostate cancer in the European Prospective Investigation into Cancer and Nutrition.

We examined plasma concentrations of phyto-oestrogens in relation to risk for subsequent prostate cancer in a case-control study nested in the European Prospective Investigation into Cancer and Nutrition. Concentrations of isoflavones genistein, daidzein and equol, and that of lignans enterolactone and enterodiol, were measured in plasma samples for 950 prostate cancer cases and 1042 matched control participants. Relative risks (RRs) for prostate cancer in relation to plasma concentrations of these phyto-oestrogens were estimated by conditional logistic regression. Higher plasma concentrations of genistein were associated with lower risk of prostate cancer: RR among men in the highest vs the lowest fifth, 0.71 (95% confidence interval (CI) 0.53-0.96, P trend=0.03). After adjustment for potential confounders this RR was 0.74 (95% CI 0.54-1.00, P trend=0.05). No statistically significant associations were observed for circulating concentrations of daidzein, equol, enterolactone or enterodiol in relation to overall risk for prostate cancer. There was no evidence of heterogeneity in these results by age at blood collection or country of recruitment, nor by cancer stage or grade. These results suggest that higher concentrations of circulating genistein may reduce the risk of prostate cancer but do not support an association with plasma lignans.

Phytic acid in wheat bran affects colon morphology, cell differentiation and apoptosis.

Wheat bran (WB) and its component phytic acid (PA) have both been shown to decrease early biomarkers of colon carcinogenesis, i.e. the PCNA labeling index of cell proliferation and certain aberrant crypt foci parameters. However, it is not known how WB and PA alter other biomarkers of colon cancer risk, such as rate of apoptosis and degree of differentiation, or how they affect colon morphology. Thus, the objectives of this study were to determine the effects of WB on these parameters, to see if PA contributes to these effects and whether there is a difference between endogenous and exogenously added PA. Five groups of azoxymethane-treated male Fischer 344 rats were fed a basal control diet (BD) or BD supplemented with either 25% wheat bran, 25% dephytinized wheat bran (DWB), 25% DWB plus 1.0% PA or 1.0% PA for 100 days. The WB, DWB and PA diets significantly increased the rate of apoptosis and cell differentiation in the whole crypt and the top 40% of the crypt. The WB, DWB and PA diets also significantly increased cell apoptosis in the bottom 60% of the crypt, while all the treatment groups significantly increased cell differentiation versus the BD group in the bottom 60% of the crypt. In addition, the WB, DWB and PA diets decreased the number of crypts per millimeter of colon, while the DWB and PA diets also decreased crypt height measured as number of cells. It is concluded that WB, partly due to its dietary fiber and endogenous PA, and exogenous PA when added to a low fiber diet can increase cell apoptosis and differentiation and favorably affect colon morphology.

The influence of phytic acid in wheat bran on early biomarkers of colon carcinogenesis.

A colon cancer protective effect of wheat bran has been observed in animal studies, but it is unclear whether the effect is due to fiber or other components, such as phytic acid (PA). Thus the objectives of this study were to determine if wheat bran alters early biomarkers of colon cancer risk, e.g. aberrant crypt foci (ACF) characteristics and indices of colonic cell proliferation, whether PA is the component responsible and whether there is a difference between endogenous and exogenously added PA. Five groups of azoxymethane-treated male Fischer 344 rats were fed for 100 days on a basal control diet (BD) or BD supplemented with either 25% wheat bran (WB), 25% dephytinized WB (DWB), 25% DWB plus 1.0% PA or 1.0% PA. All the WB-containing diets reduced the number of sialomucin-producing ACF and the degree of aberrant crypt luminal alterations in the whole colon. The WB and PA diets lowered the labeling index (LI) and the position of the uppermost labeled cell in the distal colon. Dephytinization caused an increase in the overall LI, LI in the top 40% and the position of the topmost labeled cell. Exogenous PA also reduced the number and size of ACF, the number of ACF per unit length colon as well as the number of sialomucin-producing ACF in various colon sections. It is concluded that WB, partly due to its endogenous PA, and exogenous PA when added to a low fiber diet can reduce early biomarkers of colon cancer risk.

The influence of flaxseed and lignans on colon carcinogenesis and beta-glucuronidase activity.

Flaxseed, the richest source of mammalian lignan precursors, such as secoisolariciresinol diglycoside (SD), has been shown over the short term to decrease some early markers of colon cancer risk. This study determined whether over the long term flaxseed still exerts a colon cancer protective effect, whether its effect may, in part, be due to its high content of SD and whether any change in beta-glucuronidase activity plays a role in the protective effect. Six groups of male Sprague-Dawley rats were fed for 100 days either a basal high fat (20%) diet (BD), BD supplemented with 2.5 or 5% flaxseed or 2.5 or 5% defatted flaxseed (equivalent to the respective flaxseed diets) or BD with a daily gavage of 1.5 mg SD. All rats were injected with a single dose of azoxymethane (15 mg/kg body wt) 1 week prior to commencing the dietary treatments. Urinary lignan excretion, which is an indicator of mammalian lignan production, was significantly increased in the flaxseed and defatted flaxseed groups. The total activity of cecal beta-glucuronidase was significantly increased in a dose-dependent manner by the flaxseed and defatted flaxseed diet groups. Compared with the control the number of aberrant crypts per focus was significantly reduced in the distal colon of the treated rats. Four microadenomas and two polyps were observed in the control group, but not in the treated groups. The total activity of beta-glucuronidase was positively correlated with total urinary lignan excretion and negatively with the total number of aberrant crypts and the total number of aberrant crypt foci in the distal colon. There were no significant differences between the flaxseed and the corresponding defatted flaxseed groups. It is concluded that flaxseed has a colon cancer protective effect, that it is due, in part, to SD and that the protective effect of flaxseed is associated with increased beta-glucuronidase activity.