Biomedical subjects

Inge Tetens

Publications and source records attributed to Inge Tetens.

13 recordsLinked to original sources

PubMed2005

A statistical approach based on substitution of macronutrients provides additional information to models analyzing single dietary factors in relation to type 2 diabetes in danish adults: the Inter99 study.

Most studies analyzing diet-disease relations focus on single dietary factors rather than combining different nutrients into the same statistical model. The objective of this study was to identify dietary factors associated with the probability of having diabetes identified by screening (SDM) in Danish men and women aged 30-60 y. A specific objective was to examine whether an alternative statistical approach could provide additional information to already existing statistical approaches used in nutritional epidemiology. Baseline data from the Danish population-based Inter99 study were used. The dietary intake of 262 individuals with SDM was compared with that of 4627 individuals with normal glucose tolerance (NGT) using 2 different types of multiple logistic regression models adjusted for potential confounders. The first model included single dietary factors, whereas the second model was based on substitution of macronutrients. In the models with single dietary factors, high intakes of carbohydrates, dietary fiber, and coffee were inversely associated with SDM (P < 0.01), whereas high intakes of total fat and saturated fat were positively associated with SDM (P < 0.05). A modest U-shaped association was found between alcohol consumption and SDM (P = 0.10) [corrected] Results from the substitution model showed that when 3% of energy (En%) as carbohydrate replaced 3 En% fat or alcohol, the probability of having SDM decreased by 9 and 10%, respectively (P < 0.01) [corrected] No other macronutrient substitutions resulted in significant associations. Hence, the statistical approach based on substitution of macronutrients provided additional information to the model analyzing single dietary factors.

Adult↗

PubMed2005

Dietary glycemic index, glycemic load, fiber, simple sugars, and insulin resistance: the Inter99 study.

OBJECTIVE: To examine the relationship between daily glycemic index, daily glycemic load, simple sugars, dietary fiber, and the prevalence of a measure of insulin resistance in 30- to 60-year-old nondiabetic Danish men and women. RESEARCH DESIGN AND METHODS: The Inter99 study is a nonpharmacological intervention study. We used baseline data and examined cross-sectional associations between carbohydrate-related dietary factors and an estimate of insulin resistance in 5,675 subjects at 30-60 years. The dietary intake was estimated from a self-administered food frequency questionnaire, and insulin resistance was estimated using the homeostasis model assessment of insulin resistance (HOMA-IR). Multiple regressions were performed with HOMA-IR as the dependent variable and carbohydrate-related factors as explanatory variables. All models were adjusted for age, sex, smoking, physical activity, total energy intake, BMI, and waist circumference. RESULTS: Intake of lactose was positively associated with HOMA-IR (P < 0.0001), whereas daily glycemic load and intake of glucose, fructose, dietary fiber, total carbohydrate, fruit, and vegetables were inversely associated with HOMA-IR (P < 0.05). Intake of dietary fiber explained the associations with daily glycemic load and total carbohydrate and attenuated the association with fruit and vegetables. No significant associations were observed for daily glycemic index or sucrose. CONCLUSIONS: Habitual intake of diets with a high glycemic index and high glycemic load or diets with a high content of total carbohydrate including simple sugars was not associated with the probability of having insulin resistance. Furthermore, intake of dietary fiber was inversely associated with the probability of having insulin resistance.

Adult↗

PubMed2004

A decrease in iron status in young healthy women after long-term daily consumption of the recommended intake of fibre-rich wheat bread.

BACKGROUND: Fibrerich bread and cereals are included in the recommendations of a healthy diet. OBJECTIVE: To measure the effects of long-term consumption of the recommended intake of fibre-rich wheat bread on the iron status of young healthy women with adequate iron stores. DESIGN: Four-months intervention study including healthy female subjects assigned into two groups provided daily with 300 g of fibre-rich wheat bread, prepared with or without phytase as a supplement to their habitual diet. SUBJECTS: Forty-one women aged 24.8 +/- 3.8 years (mean +/- SD) and an average BMI of 22.0 +/- 2.9 kg/m2 participated. Baseline values for serum ferritin were 45 microg/L, 22-83 (geometric mean, range) and for haemoglobin 132 g/L, 119-148 (arithmetic mean, range), respectively. RESULTS: Distribution of energy intake from protein, fat and carbohydrate, and daily intake of dietary fibre and iron were similar in the two groups and within the recommended levels. There was no effect of the phytase added to the wheat bread on the iron status of the subjects, but an effect of the intervention period. Serum ferritin and haemoglobin levels were significantly reduced by 12 +/- 1.1 microg/L (27%) (P < 0.001) and 2 +/- 0.8 g/l (1.5%) (mean +/- SE) (P < 0.05) respectively, after four months of intervention. CONCLUSIONS: The present long-term study indicates that consumption of the recommended daily intake of fibre-rich wheat bread results in an impairment of iron status in women with initially sufficient iron stores. Reduction of the phytic acid concentration in the bread was not sufficient to maintain iron status.

Adult↗

PubMed2004

Rye bran bread intake elevates urinary excretion of ferulic acid in humans, but does not affect the susceptibility of LDL to oxidation ex vivo.

BACKGROUND: Rye bread contributes an important part of the whole grain intake in the Scandinavian diet. Ferulic acid is the major phenolic compound in rye bran and is an antioxidant in vitro and may, therefore, contribute to cardioprotective effects of whole grain consumption. AIM OF THE STUDY: Firstly, to evaluate the bioavailability and potential antioxidative effects in humans of ferulic acid from rye. Secondly, to evaluate urine levels of ferulic acid as a possible biomarker of the ordinary dietary intake of ferulic acid. METHODS: We determined the urinary excretion of ferulic acid in 18 postmenopausal women after a dietary intake of rye bran or an inert wheat bran (control) in a crossover study (2 x 6 weeks with 4 weeks washout). The potential antioxidative effect of the rye bran intervention was investigated by measuring low-density lipoprotein (LDL) susceptibility to copper oxidation ex vivo. The subjects ingested rye bran enriched breads equivalent to approximately 10.2 mg ferulic acid per day. RESULTS: The urinary excretion of ferulic acid averaged approximately 4.8 mg per day during intervention with rye bran breads and approximately 1.9 mg per day on the control breads (P = 0.002). Rye bran intervention had no influence on lag time or propagation rate of the LDL oxidation ex vivo. CONCLUSIONS: The present study demonstrated that ferulic acid from rye bran is bioavailable and that the urinary concentration of ferulic acid reflects the dietary intake of this hydroxycinnamic acid. Within the period of intervention, the elevated ferulic acid did not produce a measurable antioxidative effect on the subjects' LDL. It is suggested that the determination of ferulic acid in urine is a useful biomarker to assess the intake of ferulic acid from a regular diet.

Aged↗

PubMed2004

The use of glycaemic index tables to predict glycaemic index of composite breakfast meals.

The applicability of the glycaemic index (GI) in the context of mixed meals and diets is still debatable. The objective of the present study was to investigate the predictability of measured GI in composite breakfast meals when calculated from table values, and to develop prediction equations using meal components. Furthermore, we aimed to study the relationship between GI and insulinaemic index (II). The study was a randomised cross-over meal test including twenty-eight healthy young men. Thirteen breakfast meals and a reference meal were tested. All meals contained 50 g available carbohydrate, but differed considerably in energy and macronutrient composition. Venous blood was sampled for 2 h and analysed for glucose and insulin. Prediction equations were made by regression analysis. No association was found between predicted and measured GI. The meal content of energy and fat was inversely associated with GI (R(2) 0.93 and 0.88, respectively; P<0.001). Carbohydrate content (expressed as percentage of energy) was positively related to GI (R(2) 0.80; P<0.001). Using multivariate analysis the GI of meals was best predicted by fat and protein contents (R(2) 0.93; P<0.001). There was no association between GI and II. In conclusion, the present results show that the GI of mixed meals calculated by table values does not predict the measured GI and furthermore that carbohydrates do not play the most important role for GI in mixed breakfast meals. Our prediction models show that the GI of mixed meals is more strongly correlated either with fat and protein content, or with energy content, than with carbohydrate content alone. Furthermore, GI was not correlated with II.

Adult↗

PubMed2004

No difference in body weight decrease between a low-glycemic-index and a high-glycemic-index diet but reduced LDL cholesterol after 10-wk ad libitum intake of the low-glycemic-index diet.

BACKGROUND: The role of glycemic index (GI) in appetite and body-weight regulation is still not clear. OBJECTIVE: The objective of the study was to investigate the long-term effects of a low-fat, high-carbohydrate diet with either low glycemic index (LGI) or high glycemic index (HGI) on ad libitum energy intake, body weight, and composition, as well as on risk factors for type 2 diabetes and ischemic heart disease in overweight healthy subjects. DESIGN: The study was a 10-wk parallel, randomized, intervention trial with 2 matched groups. The LGI or HGI test foods, given as replacements for the subjects' usual carbohydrate-rich foods, were equal in total energy, energy density, dietary fiber, and macronutrient composition. Subjects were 45 (LGI diet: n = 23; HGI diet: n = 22) healthy overweight [body mass index (in kg/m(2)): 27.6 +/- 0.2] women aged 20-40 y. RESULTS: Energy intake, mean (+/- SEM) body weight (LGI diet: -1.9 +/- 0.5 kg; HGI diet: -1.3 +/- 0.3 kg), and fat mass (LGI diet: -1.0 +/- 0.4 kg; HGI diet: -0.4 +/- 0.3 kg) decreased over time, but the differences between groups were not significant. No significant differences were observed between groups in fasting serum insulin, homeostasis model assessment for relative insulin resistance, homeostasis model assessment for beta cell function, triacylglycerol, nonesterified fatty acids, or HDL cholesterol. However, a 10% decrease in LDL cholesterol (P < 0.05) and a tendency to a larger decrease in total cholesterol (P = 0.06) were observed with consumption of the LGI diet as compared with the HGI diet. CONCLUSIONS: This study does not support the contention that low-fat LGI diets are more beneficial than HGI diets with regard to appetite or body-weight regulation as evaluated over 10 wk. However, it confirms previous findings of a beneficial effect of LGI diets on risk factors for ischemic heart disease.

Adult↗

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↗