Biomedical subjects

Inge Tetens

Publications and source records attributed to Inge Tetens.

25 records · Page 2Linked to original sources

PubMed2004

Intake of whole grains and vegetables determines the plasma enterolactone concentration of Danish women.

The mammalian lignan enterolactone (ENL), which is produced from dietary plant-lignan precursors by the intestinal microflora, may protect against breast cancer and other hormone-dependent cancers. This cross-sectional study examined which variables related to diet and lifestyle were associated with high plasma concentrations of ENL in Danish postmenopausal women. Plasma ENL was measured by time-resolved fluoroimmunoassay in 857 Danish women aged 50-64 y who participated in a prospective cohort study. Diet was assessed using a semiquantitative FFQ, and background information on lifestyle was collected using a self-administered questionnaire. Multiple analyses of covariance were completed in two steps. The median plasma ENL concentration was 27 nmol/L (range 0-455 nmol/L). In covariance analyses, positive associations were found between consumption of cereals, vegetables, and beverages and plasma ENL concentration. When analyzing subgroups of these food groups, the associations were confined to whole-grain products, cabbage, leafy vegetables, and coffee. For fat and the nondietary variables, negative associations between BMI, smoking, and frequency of bowel movements and plasma ENL concentration were observed. These data show that foods high in ENL precursors are associated with high concentrations of ENL. Furthermore, smoking, frequent bowel movements, and consumption of fat seems to have a negative affect on the ENL concentration. In conclusion, whole grains and vegetables are the most important dietary providers of plant lignans for the concentration of ENL in Danish postmenopausal women, and if ENL is found to protect against cancer or heart disease, the intake of whole grains and vegetables should be increased.

4-Butyrolactone↗

PubMed2004

A single measurement is inadequate to estimate enterolactone levels in danish postmenopausal women due to large intraindividual variation.

Single measurements of enterolactone (ENL) used in epidemiologic studies are influenced by intraindividual variation. The objective of this controlled study was to investigate short-term intraindividual variations in serum and urine ENL. Based on these variations, the number of samples required to describe the basal ENL level was estimated. Healthy Danish postmenopausal women (n = 6) aged 54-67 y completed 3 study periods of 24 h within 2 mo. Blood samples were collected at 0, 4, 6, 8, 12, and 24 h and 24-h urine samples were collected. A low-lignan, standardized diet of 3 meals was served. ENL was measured by time-resolved fluoroimmunoassay. Intraindividual and interindividual variations were estimated using a mixed model with repeated measurements. Significant and systematic intraindividual within-day variations (CV) of 31% were observed in serum. Intraindividual day-to-day variations were 56% and overall intraindividual variation of samples collected at random times and on different days was estimated to be 64%. Describing this overall variation required 7 blood samples when estimated with a precision of 50% and 95% confidence. Day-to-day variations in 24-h urine samples were 49%. Large within-day and day-to-day variations suggest that a single measurement of ENL is inadequate to estimate the basal ENL level.

4-Butyrolactone↗

PubMed2003

The leafy vegetable amaranth (Amaranthus gangeticus) is a potent inhibitor of calcium availability and retention in rice-based diets.

Improvement in the nutritional quality of Bangladeshi rice-based diets is sought through increasing the amounts of vegetables, fish and legumes consumed. The aim of the present study was to compare the effects of rice-based diets on selected parameters of Ca and P availability and retention in young, growing rats. The study was designed as a randomised balance trial with five diets, eight animals per diet, and two balance periods of 1 week each. Apart from diet 1, which was a pure rice diet, the other four diets were composite diets and included the leafy vegetable, amaranth leaves (Amaranthus gangeticus), the small fish, mola (Amblypharyngodon mola), and lentils (Lens culinaris) in different amounts to simulate the average rural rice-based diet, the recommended diet, the recommended diet diluted with starch, and the recommended diet excluding amaranth leaves. The inclusion of amaranth leaves, mola and lentils significantly improved N and growth retention in the rats compared with the pure rice diet. However, a minor addition of amaranth (0.66 g/100 g DM) significantly reduced the fractional Ca absorption and retention. Femur bone mass and Ca and P densities were significantly lower in the rats fed the diets that included amaranth leaves. The observed inhibitory effect of the amaranth leaves on Ca absorption and utilisation was probably due to the oxalate content. It is concluded that the formulation of a recommended diet cannot be based only on nutrient content values of individual food components due to interactions between nutrients and anti-nutrients in the diet.

Alkaline Phosphatase↗

PubMed2003

Estimated nutrient intakes and adequacies in Bangladesh change when newer values for vitamin A, iron and calcium in commonly consumed foods are applied.

A food consumption survey was conducted in rural Bangladesh in January-March 1996 using a 24-h food weighing method. Intakes and adequacies of energy, vitamin A, vitamin C, iron and calcium were estimated for 81 children (aged 24-71 months) and 182 women (aged 18-45 years) using three sets of food composition tables. The local food composition table was modified with newer values for nutrient contents of foods identified as important for the contribution of vitamin A and iron. Significant differences in estimated dietary intakes and adequacies were found for vitamin A and iron when different sets of food composition values were used. This study shows that up-to-date chemical analyses of foods selected on the basis of a high frequency of consumption and a large contribution of the nutrients in focus is a useful approach in improving the quality of food composition tables, resulting in greater accuracy of estimates of nutrient intakes and adequacies.

Adolescent↗

PubMed2003

Rice-based diets in rural Bangladesh: how do different age and sex groups adapt to seasonal changes in energy intake?

BACKGROUND: Seasonality has been recognized as a key determinant of human energy balance, especially in low-income countries. OBJECTIVE: The objective was to test the hypothesis that, in rural Bangladesh, different age and sex groups adapt similarly to seasonal changes in energy intake (EI). DESIGN: A prospective study was carried out in 2 rural Bangladeshi villages in the lean and peak seasons. Data on anthropometric measures (weight, height, and midupper arm circumference) and dietary food intake (collected with the use of a 24-h food weighing method) were obtained from all subjects from 304 households. RESULTS: The average EI increased from a least-squares mean (+/- SE) of 7.87 +/- 0.10 MJ x person(-1) x d(-1) in the lean season to 9.47 +/- 0.13 MJ x person(-1) x d(-1) in the peak season. In children and adolescents aged < 18 y of age, the prevalence of underweight (weight-for-age) was not significantly different (56%) in the 2 seasons. Among adults, a significantly higher prevalence of chronic energy deficiency [body mass index (in kg/m(2)) < 18.5] was observed in the peak season (67%) than in the lean season (61%), despite a higher EI in the peak season. Other determinants of seasonal nutritional status are presented. CONCLUSIONS: Seasonal fluctuations in EI were substantial in all age and sex groups. Children and adolescents showed no significant seasonal changes in the prevalence of underweight, which indicated that they adapted to changes in EI. In adults, the season in which EI was high coincided with average weight loss, which indicated that adults did not adapt fully to seasonal fluctuations in EI and that seasonal energy expenditure is probably a major determinant of nutritional status.

Adaptation, Physiological↗

PubMed2003

Rye bread in the diet of pigs enhances the formation of enterolactone and increases its levels in plasma, urine and feces.

To obtain new insight into the quantitative and qualitative metabolism of rye and wheat lignans, we performed three series of experiments with catheterized pigs. Two diets with similar levels of dietary fiber and macronutrients but with contrasting levels of plant lignans (isolariciresinol, lariciresinol, matairesinol, pinoresinol, secoisolariciresinol and syringaresinol) were prepared from rye (high in lignans) and wheat (low in lignans) soft and crisp breads. In two series of experiments we quantified the uptake from the gut of enterolactone in four pigs fitted with catheters in the portal vein and mesenteric artery and with an ultrasonic flow probe attached to the portal vein to monitor the blood flow. In a third study with six pigs, we quantified the bioavailability of the plant lignans that can be converted to enterolactone (lariciresinol, matairesinol, pinoresinol, secoisolariciresinol and syringaresinol) and the concentration in the peripheral blood. Plant and mammalian lignans in diets and stool were analyzed by isotope dilution gas chromatography-mass spectrometry and enterolactone in plasma and urine determined by time-resolved fluoroimmunoassay. There was a significantly higher formation of enterolactone in pigs fed the rye diet, and higher fecal and urinary excretion and circulating levels of mammalian lignans than in pigs fed the wheat diet. The conversion of mammalian lignan precursors to enterolactone was 48% with the wheat diet and 60% with the rye diet. Mammalian lignans are absorbed by passive diffusion from the large intestine and a substantial fraction of the absorbed mammalian lignans undergoes enterohepatic circulation, resulting in low diurnal variation in plasma levels of enterolactone.

4-Butyrolactone↗

PubMed2003

Leptin and bone mineral density: a cross-sectional study in obese and nonobese men.

Leptin has been suggested to decrease bone mineral density (BMD). This observational analysis explored the relationship between serum leptin and BMD in 327 nonobese men (controls) (body mass index 26.1 +/- 3.7 kg/m(2), age 49.9 +/- 6.0 yr) and 285 juvenile obese men (body mass index 35.9 +/- 5.9 kg/m(2), age 47.5 +/- 5.1 yr). Whole-body dual-energy x-ray absorptiometry scan measured BMD, fat mass, and lean mass. Fasting serum leptin (nanograms per milliliter) was strongly associated with fat mass (kilograms) in both controls (r = 0.876; P < 0.01) and juvenile obese (r = 0.838; P < 0.001). An inverse relation between BMD adjusted for body weight and serum leptin emerged in both the control group (r = -0.186; P < 0.01) and the juvenile obese group (r = -0.135; P < 0.05). In a multiple linear regression, fat mass, lean body mass, and occupational physical activity were positively associated with BMD in the control group, whereas in the juvenile obese, only lean body mass was positively associated with BMD and smoking negatively associated with BMD. Our study supports that leptin is inversely associated with BMD and may play a direct role in the bone metabolism in nonobese and obese Danish males, but it also stresses the fact that the strong covariation between the examined variables is a shortcoming of the cross-sectional design.

Adult↗