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J C Seidell

Publications and source records attributed to J C Seidell.

At least 163 records · Page 9Linked to original sources
PubMed1992

Changes in fat-free mass in obese subjects after weight loss: a comparison of body composition measures.

Estimates of body composition by densitometry were made in 84 apparently healthy subjects (42 men, 42 women) with a mean age of 40 +/- 6 years (mean +/- s.d.), before and after weight loss. The initial body mass index (BMI) was 30.7 +/- 2.3 kg/m2 and the achieved weight loss on a 4.2 MJ/day energy deficit diet for 13 weeks was 12.2 +/- 3.7 kg. The results by densitometry were compared with estimates obtained by four other techniques: deuterium oxide dilution, skinfold thickness, bioelectrical impedance (three equations) and BMI (two equations). The fat-free mass (FFM) loss estimated by densitometry in men and women was 2.8 +/- 1.8 kg and 1.3 +/- 1.3 kg respectively. The dilution technique gave comparable results with densitometry. The losses of FFM assessed by skinfold thicknesses, BMI and impedance equations were almost similar, but significantly larger than the reduction in FFM measured by densitometry. These deviations were mainly the result of significantly larger differences from densitometry before compared to after weight loss. No correlation was found between change in FFM by densitometry and change in resistance measured by the bioelectrical impedance method in both sexes. It is concluded that application of published prediction formulae in weight loss studies are less appropriate and will lead to changes in FFM that are significantly different from the changes estimated by densitometry or deuterium oxide dilution.

Adult↗
PubMed1991

Polyunsaturated fatty acids in adipose tissue in European men aged 38 years in relation to serum lipids, smoking habits, and fat distribution.

Fat biopsies were taken from 327 men aged 38 years from five different European communities in 1988-1989. Linoleic acid content varied widely (F = 110.6, p less than 0.001) and was lowest in men from Poland (8.6%) and highest in men from Belgium (16.7%). Adipose tissue content of alpha-linolenic acid was subject to less variation (F = 13.9, p less than 0.001) and was lowest in men from Italy (0.5%) and highest in men from Sweden and the Netherlands (0.9%). In analysis combining information from all centers, linoleic acid was negatively correlated to low density lipoprotein cholesterol (r = -0.15, p less than 0.01) and total cholesterol (r = -0.17, p less than 0.01). alpha-Linolenic acid was negatively correlated to serum triglycerides only (r = -0.14, p less than 0.05). These fatty acids were not related to body mass index, waist/hip ratio, or smoking habits. The authors conclude that there are major differences in the fatty acid composition of adipose tissue in different European populations but that these do not explain the significant differences in serum high density lipoprotein cholesterol and serum triglycerides among the different populations.

Adipose Tissue↗
PubMed1991

Body fat distribution in relation to physical activity and smoking habits in 38-year-old European men. The European Fat Distribution Study.

The authors studied 512 European men all born in 1950 from six different towns in the period October 1988 to May 1989. Anthropometric measurements were taken, including weight, height, and circumferences (waist, hip, thigh). Educational level, activity scores and information on smoking habits were obtained from a questionnaire. Higher educational level was associated with lower body mass index, waist/hip ratio, and waist/thigh ratio. The sports activity score was negatively related to waist/hip ratio (beta +/- standard error of the mean (SEM): -0.009 +/- 0.003) and waist/thigh ratio (-0.041 +/- 0.007), and this could be attributed to a negative relation with waist circumference and a positive relation to thigh circumference. Smoking habits were not related to body mass index but heavy smokers had larger waist circumferences (difference +/- SEM: 1.4 +/- 0.5 cm) as well as higher waist/hip ratios (difference +/- SEM: 0.014 +/- 0.005) and waist/thigh ratios (0.043 +/- 0.013) compared with men who never smoked. These associations between activity scores and smoking habits and fat distribution remained after adjustment for each other and for body mass index and educational level. The authors conclude that physical activity and smoking are independently related to indicators of fat distribution and may be potential confounders in the relations between fat distribution, risk factors, and disease.

Adipose Tissue↗
PubMed1991

Fat distribution and gender differences in serum lipids in men and women from four European communities.

We studied male/female differences in serum lipids in randomly selected 38-year-old men (n = 337) and women (n = 342) from various cities in The Netherlands, Sweden, Italy, and Poland. Overall, men had higher triglycerides and total cholesterol levels and lower HDL-levels compared to women (P less than 0.001). Adjustment for smoking habits, city, and body mass index did not remove the gender difference. Further adjustments for waist circumference alone and waist/hip and waist/thigh circumference ratio removed the gender differences in serum triglycerides and total cholesterol. Only adjustment for waist/thigh ratio removed the gender difference in HDL-cholesterol but linear relationships were different in men and women. The average male/female difference in serum lipids, particularly for total and LDL-cholesterol varied considerably among centers. In analyses of the data from the separate centers we found that sex differences in serum triglycerides and HDL-cholesterol in all 4 centers disappeared when adjusted for waist circumference alone and for waist/hip and waist/thigh ratio. For total and LDL-cholesterol, however, adjustment for circumference ratios tended to increase the male/female difference in 2 of the 4 centers. It is concluded that, in European men and women, fat distribution may be responsible for male/female differences in serum triglycerides but that such conclusions are less clear for HDL-, total- and LDL-cholesterol.

Adipose Tissue↗
PubMed1991

Body fat distribution in relation to serum lipids and blood pressure in 38-year-old European men: the European fat distribution study.

A study on 512 38-year-old European men selected from 6 different towns was conducted. There were significant differences between the centers in averages of anthropometric variables (except for thigh circumference), serum lipids (except for LDL-cholesterol), and blood pressure. In the pooled material, body mass index (BMI) as well as waist circumference, waist/hip ratio and waist/thigh ratio and subscapular skinfold were positively correlated to serum triglycerides, total cholesterol, LDL-cholesterol, and blood pressure and negatively with HDL-cholesterol. After adjustment for BMI, waist, waist/hip, and waist/thigh were all still significantly correlated with serum triglycerides (P less than 0.001). In addition, waist/hip and waist/thigh ratio showed significant partial correlations with total cholesterol (r = 0.16, P less than 0.001, r = 0.10, P less than 0.05 respectively), and diastolic blood pressure (r = 0.10, P less than 0.05, r = 0.09, P less than 0.05 respectively). In addition, waist/hip was, independently of BMI, correlated to LDL-cholesterol (r = 0.12, P less than 0.01), and waist/thigh ratio with HDL-cholesterol (r = -0.12, P less than 0.01). The partial association between waist/thigh with HDL cholesterol became insignificant after adjustment for smoking habits and physical activity. Adjustment for differences in anthropometric measurements did not explain the differences in serum lipids and blood pressure between the centers. The authors conclude that indicators of body fat distribution are associated with unfavorable risk profiles for cardiovascular disease in European men covering a large geographical and cultural variety and a wide range of body measurements and cardiovascular risk factors.

Adipose Tissue↗
PubMed1991

Fasting serum insulin in relation to fat distribution, serum lipid profile, and blood pressure in European women: the European Fat Distribution Study.

Samples of 38-year-old women were randomly selected from five European centers: Ede (The Netherlands), Warsaw (Poland), Gothenburg (Sweden), Verona (northern Italy), and Afragola (Naples-southern Italy). In total, 452 healthy women were studied. Anthropometric measurements were taken by one operator in each country after common training of all operators and blood parameters of all women were determined in one laboratory. Body mass index (BMI) was different among centers, mainly due to the higher values in southern Italy. Women from southern Europe had more central fat distribution than women from north European centers. Fasting serum insulin was higher in women from Poland and The Netherlands than in the other three centers. After adjustment for BMI, fasting insulin was significantly related to subscapular skinfold, subscapular to triceps skinfold ratio, waist circumference, and waist to thigh circumference ratio, although the partial correlations varied somewhat between the centers. In the pooled data, waist circumference showed the highest correlations with fasting serum insulin when adjusted for BMI. Fasting serum insulin showed significant partial correlations, adjusted for BMI, with lipid profile and blood pressure only in women from the two Italian centers. In the pooled data, fasting serum insulin was significantly positively correlated with serum triglycerides and total cholesterol and negatively to high-density lipoprotein (HDL) cholesterol and HDL/total cholesterol, independently of BMI and waist circumference. While blood pressure was not related to insulin in the pooled women, when adjusted for BMI and waist circumference; here as well, there were some differences in relationships between the centers.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗
PubMed1991

Body mass index as a measure of body fatness: age- and sex-specific prediction formulas.

In 1229 subjects, 521 males and 708 females, with a wide range in body mass index (BMI; 13.9-40.9 kg/m2), and an age range of 7-83 years, body composition was determined by densitometry and anthropometry. The relationship between densitometrically-determined body fat percentage (BF%) and BMI, taking age and sex (males = 1, females = 0) into account, was analysed. For children aged 15 years and younger, the relationship differed from that in adults, due to the height-related increase in BMI in children. In children the BF% could be predicted by the formula BF% = 1.51 x BMI-0.70 x age - 3.6 x sex + 1.4 (R2 0.38, SE of estimate (SEE) 4.4% BF%). In adults the prediction formula was: BF% = 1.20 x BMI + 0.23 x age - 10.8 x sex - 5.4 (R2 0.79, SEE = 4.1% BF%). Internal and external cross-validation of the prediction formulas showed that they gave valid estimates of body fat in males and females at all ages. In obese subjects however, the prediction formulas slightly overestimated the BF%. The prediction error is comparable to the prediction error obtained with other methods of estimating BF%, such as skinfold thickness measurements or bioelectrical impedance.

Adipose Tissue↗
PubMed1991

Sex and age specific prediction formulas for estimating body composition from bioelectrical impedance: a cross-validation study.

In 827 male and female subjects, with a large variation in body composition and an age range of 7-83 years, body composition was measured by densitometry, anthropometry and bioelectrical impedance. The relationship between densitometrically determined fat free mass (FFM) with body impedance (R), body weight (W) and body height (H) was analysed, taking age and sex into account. The intercept of the regression equation FFM = a x H2/R + b was found to be age, and (at older ages) sex dependent, increasing from age 7 to age 15, and slowly decreasing after age 16. Therefore the population was subdivided into two age categories, the one 15 years and younger, and the other 16 years and older. Each age category was randomly divided into two groups, A and B. In each age category the developed prediction formula for group A was cross-validated in group B, and vice versa. No statistically and biologically meaningful differences between predicted and measured FFM were observed in either group. Therefore the data of group A and B in each age category were combined. The best fitted prediction formula at ages less than or equal to 15 was: FFM = 0.406 x 10(4) x H2/R + 0.360 W + 5.58 H + 0.56 Sex - 6.48: n = 166, R2 = 0.97, SEE = 1.68 kg (cv% = 4.9 percent); and at ages greater than or equal to 16: FFM = 0.340 x 10(4) x H2/R + 15.34 H + 0.273 W - 0.127 age + 4.56 sex - 12.44: n = 661, R2 = 0.93, SEE = 2.63 kg (cv% = 5.0 percent).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

Abdominal fat predominance in women is associated with a decreased prevalence of the high risk P2, DY mammographic breast patterns.

Body fat distribution was studied in relation to mammographic breast morphology in a cross-sectional sample of 583 women aged 41-75 years participating in the DOM project, a regional breast cancer detection project in Utrecht, the Netherlands. The waist/hip ratio (WHR) was used as an indicator of body fat topography. Mammographic breast morphology was categorized according to the parenchymal breast patterns (N1, P1, P2, DY) as defined by Wolfe. Multivariate associations between the waist/hip ratio, Quetelet's index, age and parity and mammographic parenchymal patterns were tested by multiple linear logistic regression. Independently of age, parity and the degree of obesity, women with a high WHR ratio, i.e. with a predominant fat accumulation in the abdominal region, were significantly less likely to have the high risk P2, DY mammographic parenchymal pattern than women with a low WHR, i.e. with a preferential gluteal-femoral fat accumulation.

Abdomen↗
PubMed1990

[Waist-to-hip ratio in Dutch women and its relationship with self-reported diabetes mellitus, hypertension and cholecystectomy].

The waist-to-hip circumference ratio is recognized as a measure of body fat distribution and as a risk indicator of premature mortality. The distribution of waist-to-hip ratio values in 12,000 Dutch women aged between 40 and 75 years is presented. In addition, the statistical associations between the waist-to-hip ratio and the degree of overweight as well as the prevalence of self-reported diabetes mellitus, hypertension, and cholecystectomy are described. The odds ratios for the prevalence of these disorders increased progressively with increasing waist-to-hip ratio. The age-adjusted odds ratios for women with a waist-to-hip ratio greater than 0.85 in comparison to those with a waist-to-hip ratio less than 0.70 were 4.8, 4.6 and 5.8 for diabetes mellitus, hypertension, and cholecystectomy respectively. The presented data on waist-to-hip ratio can, in combination with Quetelet's index, serve as a guide in the interpretation of measured waist-to-hip ratios in women between 40 and 75 years of age.

Adult↗
PubMed1990

Visceral fat accumulation in men is positively associated with insulin, glucose, and C-peptide levels, but negatively with testosterone levels.

Twenty-three healthy men (age 25 to 50 years), covering a wide range of fatness and body fat distribution, were studied. An oral glucose tolerance test was performed and adipose tissue areas were calculated from computed tomography (CT) scans made at the level of L4/L5. Visceral fat area was associated with elevated concentrations of insulin and C-peptide and with glucose intolerance before and after the oral glucose load. Concentrations of sex-hormone-binding globulin (SHBG), as well as total and free testosterone, were negatively correlated with waist/hip circumference ratio and visceral fat area and also negatively associated with increased glucose, insulin, and C-peptide concentrations. In multiple linear regression, adjusting for age, body mass index, and visceral fat area, serum concentrations of free testosterone were still negatively correlated with glucose, insulin, and C-peptide levels. Without claiming any causality in the observed associations, we conclude that, unlike in women, abdominal fat distribution, insulin, glucose, and C-peptide levels are negatively associated with serum testosterone levels in men.

Adipose Tissue↗
PubMed1990

Androgenicity in relation to body fat distribution and metabolism in 38-year-old women--the European Fat Distribution Study.

We studied fat distribution and metabolic risk factors in 434 38-year old women selected from population registrars in 5 cities in different parts of Europe. In the present study we focussed on the geographical variation in serum concentrations of free testosterone and its relation to measures of obesity, fat distribution and indicators of cardiovascular risk (serum lipids, insulin, and blood pressure). There were significant differences in free testosterone levels (F = 5.4, p less than 0.001) with lowest levels in Polish women (mean +/- SEM: 1.56 +/- 0.08 pg/ml) and highest in women from Italy (2.07 +/- 0.12 pg/ml). In the pooled data, free testosterone levels were correlated with several anthropometric variables (strongest with subscapular/triceps ratio r = 0.27, with subscapular skinfold and waist/thigh circumference ratio r = 0.25 p-values less than 0.001). In addition, free testosterone was positively correlated with serum total cholesterol (r = 0.11), HDL/total cholesterol fraction (r = 0.12), serum insulin (r = 0.20) and diastolic blood pressure (r = 0.15). These associations remained significant after adjustment for body mass index and waist/thigh ratio (not for diastolic blood pressure) but were no longer significant after further adjustment for insulin levels. There were considerable differences in strength of the associations mentioned between the 5 centers. We conclude that degree of obesity, fat distribution and serum levels of free testosterone all, to a limited degree, contribute to the metabolic profile of randomly selected 38-year old women but that adjustment for such variables increases the differences in metabolic profiles between women from different centers of Europe.

Adipose Tissue↗
PubMed1990

Imaging techniques for measuring adipose-tissue distribution--a comparison between computed tomography and 1.5-T magnetic resonance.

We developed a method for calculating adipose-tissue areas from transverse body scans by magnetic-resonance imaging (MRI). The method is based on an inversion recovery experiment (repetition time 820 ms, inversion delay time 300 ms, and echo time 20 ms). Total-fat areas and subcutaneous-fat areas were calculated by this method and by computed tomography (CT) from abdominal scans taken in seven male volunteers. The SEE ranged from 4.4 cm2 (CV 4.4%) for subcutaneous-fat areas to 8.3 cm2 (CV 12.8%) for visceral-fat areas. The reproducibility of measuring fat areas with MRI was assessed in seven other volunteers (four males, three females). The average errors of the method for different fat areas were 5.4%, 10.6%, and 10.1% for total-, visceral-, and subcutaneous-fat areas, respectively. We conclude that CT and MRI may yield different absolute values of fat areas (especially visceral fat) but that the ranking of individuals on the basis of their fat areas will be similar by both methods.

Adipose Tissue↗
PubMed1990

Fat distribution in European women: a comparison of anthropometric measurements in relation to cardiovascular risk factors.

In this study in 437 women born in 1948 selected from five European towns we show that several anthropometric measurements are consistently and significantly associated with a metabolic risk profile in premenopausal women of 38 years of age. Among the circumferences, breast and waist circumference were, after adjustment for body mass index positively correlated with diastolic blood pressure, serum total cholesterol, HDL-cholesterol (negative associations), serum triglycerides, and serum insulin. The optimal level for measuring waist circumference was determined as being midway between the lower rib margin and the superior anterior iliac crest. Circumference ratios generally did show less consistent and similar or lower correlations with diastolic blood pressure, serum cholesterol and serum insulin. Waist/thigh circumference ratio showed the strongest partial associations with HDL-cholesterol and serum triglycerides among all anthropometric variables studied. The authors conclude that, independently of the degree of fatness, indicators of truncal fat distribution (in the region of the breast as well as the abdomen) are related to an unfavourable risk profile in European premenopausal women. The study gives a rationale for selecting the most informative anthropometric measurements to be added to height and weight in epidemiological studies.

Abdomen↗