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J A Weststrate

Publications and source records attributed to J A Weststrate.

At least 55 records · Page 3Linked to original sources
PubMed1995

Short-term effects of high-fat and low-fat/high-SPE croissants on appetite and energy intake at three deprivation periods.

The short-term satiating effects of croissants with different amounts of fat and sucrose polyester (SPE) followed by three lengths of deprivation were investigated. Sixteen male and 18 female normal-weight subjects each received six different experimental conditions in a two x three factorial design. Energy content was the first factor with two levels: 1.80 MJ and 3.45 MJ. The second factor was the deprivation period after the lunch preload with three levels: 0.25, 2.25, and 4.75 h. Subjects ate ad lib after the deprivation period. The effects of the croissants were determined by motivational ratings and reported food consumption on the study day and the day after the study day. The SPE croissants (1.80 MJ) and the high-fat croissants (3.45 MJ) did not result in different subsequent energy intakes. Differences in energy intake were found between the three deprivation conditions, with the lowest intake with the 4.75-h deprivation condition. This was due to differences in the energy intake during the afternoon. The two energy levels of the preloads had similar effects on the motivational ratings. Higher appetite ratings were found after the 4.75-h compared to the 0.25 h and the 2.25-h deprivation condition.

Adult↗
PubMed1995

Short-term satiating effect of the fat replacer sucrose polyester (SPE) in man.

The effects of different amounts of the non-absorbable fat replacer sucrose polyester (SPE), water, and fat added to six warm preload lunches on feelings of appetite and food intake were investigated in two studies that were replicates of each other. In the first study thirty-nine subjects consumed rice preloads; in the second study thirty-five subjects consumed macaroni preloads. The six preloads were fixed on three energy levels: 1.8, 2.7, or 3.7 MJ. At 2 h after preload consumption a test-meal buffet of thirty-one products was presented. Food intake was recorded on the study day, and the day after the study day. For women no energy compensation occurred in either study. Men showed a tendency to compensate for the energy differences between the preloads. However, when the fat of the preloads was replaced by SPE, energy compensation was less than 50% and non-significant. Statistically significant energy compensation (66%) was found when fat was replaced by water. No macronutrient-specific compensation occurred in men or women in either study. Lower total fat and energy intakes were found with the preloads where fat was replaced by SPE compared with the preloads containing fat. The appetite ratings were in line with the energy intake values, with no differences in women, and higher appetite ratings after the lower energy preloads in men. This short-term study indicates that SPE may be a useful aid to reduce fat and energy intakes.

Adult↗
PubMed1995

Sucrose polyester and plasma carotenoid concentrations in healthy subjects.

A double-blind, placebo-controlled crossover study of the effects of the nonabsorbable fat analogue sucrose polyester (SPE; 12.4 g/d) on plasma concentrations of five different carotenoids and vitamin E in 21 volunteers, and a double-blind, placebo-controlled parallel comparison study in 53 subjects of the effect of 3 g SPE/d on plasma concentrations of two different carotenoids were undertaken. SPE-containing margarine added to the main meal was used. SPE (12.4 g/d) reduced plasma of beta-carotene concentrations by 0.13 mumol/L (34%, P = 0.0001) and concentrations of lycopene by 0.14 mumol/L (52%, P = 0.0001). Smaller but significant reductions were found for plasma concentrations of beta-cryptoxanthin, lutein, zeaxanthin, and vitamin E. SPE (3 g/d) reduced plasma concentrations of beta-carotene by 0.094 mumol/L (20% P = 0.0001) and concentrations of lycopene by 0.12 mumol/L (38%, P = 0.0001). Even at low doses, SPE strongly reduces plasma carotenoid concentrations. This finding merits careful consideration in assessing the long-term health effects of SPE-containing consumer foods.

Adult↗
PubMed1995

Positional distribution of stearic acid and oleic acid in a triacylglycerol and dietary calcium concentration determines the apparent absorption of these fatty acids in rats.

In this study the effect of the positional distribution of stearic acid (18:0) and oleic acid (18:1) in a triacylglycerol on absorption of fat, energy and nutrients was investigated in young rats. In addition the effect of dietary calcium on these variables was studied. Forty rats were fed purified diets containing either a fat blend high in 2-oleoyl-distearate or a fat blend high in 1-oleoyl-distearate. Both diets were given at low (0.3 g/100 g) and high (1.0 g/100 g) dietary calcium concentrations. Total fat absorption, expressed as the percentage of fat intake, was significantly lower in rats fed 2-oleoyl-distearate compared with 1-oleoyl-distearate at both dietary calcium concentrations. When expressed as absolute figures, the lower fat absorption in rats fed 2-oleoyl-distearate compared with 1-oleoyl-distearate only reached statistical significance at the high dietary calcium concentration. The reduced absorption of total fat was mainly caused by the lower absorption of stearic acid. The percentage of, but not absolute, absorption of oleic acid and energy were lower in rats fed 2-oleoyl-distearate. Absolute and percentage of calcium absorption were lower in rats fed 2-oleoyl-distearate compared with 1-oleoyl-distearate. Absolute and percentage of magnesium absorption were not significantly affected by the positional distribution of stearic acid and oleic acid in the triacylglycerol, but were decreased at a high dietary calcium concentration. We concluded that the lowered stearic acid absorption from 2-oleoyl-distearate compared with 1-oleoyl-distearate might have been due to the greater formation of insoluble calcium and magnesium soaps in the intestine.

Absorption↗
PubMed1995

Interaction between physical structure and amylose:amylopectin ratio of foods on postprandial glucose and insulin responses in healthy subjects.

OBJECTIVE: To study the effect of amylose content on postprandial glucose and insulin responses in healthy subjects by serving fixed amounts of simple starchy foods with a varying but strictly controlled water, fat and guar gum content. DESIGN: A blind, randomised, balanced cross-over study. SETTING: The kitchen of the Nutrition Research Unit in the Unilever Research Laboratorium. SUBJECTS: Apparently healthy employees of Unilever Research Laboratorium. INTERVENTIONS: Subjects consumed, after an overnight fast, either a drink (12 men), a pudding (6 men and 6 women), a roll without (5 men and 6 women) or a roll with guar gum (12 men) as breakfast and the same amount of the same food as mid-morning snack. Each subject consumed the experimental food prepared in four ways: either with high- or normal-amylose starch, and with or without added fat. At 30 and 90 min after consumption of the breakfast or the snack a blood sample was taken for determination of glucose and insulin. RESULTS: Raising the amount of amylose in starchy drinks and puddings, but not in rolls, lowered postprandial glucose and insulin responses. Fat addition to starchy drinks, puddings and rolls attenuated postprandial glucose responses, irrespective of the amount of amylose or guar gum present. Addition of guar gum to rolls reduced glucose and insulin responses. Glucose tolerance tended to be less after consumption of the experimental foods as mid-morning snack than after consumption as breakfast. CONCLUSION: The physico-chemical composition of foods does influence the effect of the amylose:amylopectin ratio in starchy foods on postprandial glucose and insulin responses.

Amylopectin↗
PubMed1995

Fat and obesity.

Explore the source record for details and available documents.

Animals↗
PubMed1993

The effects of preloads varying in physical state and fat content on satiety and energy intake.

This study investigated the effect of the physical state and fat content of a preload on feelings of hunger and satiety and subsequent energy intake. Thirty-three normal-weight female subjects each received nine different 550-ml preloads which were served as breakfast. The preloads differed in physical state and fat level. There were three types of physical state (liquid, solid with locust bean gum, and solid with gelatin) combined with three energy levels (0.42, 1.67, and 3.35 MJ). The energy differences were due only to differences in fat content. Subjects were not allowed to eat or drink (except water) for 3.5 h after preload consumption. In this period they rated their feelings of appetite. Subjects recorded their voluntary food intake for the remainder of the study day and the day after the study day. There were no effects of the different amounts of fat or the three different physical states on energy intake during the remainder of the day or the day after. With respect to the appetite ratings, however, it appeared that the solid preloads were more satiating than the liquid preloads and the solid preloads were more satiating with fibre (locust bean gum) than without fibre (gelatin). The high-fat preloads were more satiating than the low-fat preloads.

Adult↗
PubMed1993

Effects of the amylose content of breakfast and lunch on postprandial variables in male volunteers.

The impact of the amylose content of breakfast and lunch on postprandial variables was investigated in 22 normal-weight healthy males. Areas under the curve for insulin but not glucose were significantly smaller after the high-amylose breakfasts. Areas under the curve for both glucose and insulin were significantly smaller after the high-amylose lunches. Breath-hydrogen excretion over 14 h after breakfast indicated good digestibility of both types of meals. No systematic effect of amylose content on appetite or fullness ratings was observed. The amylose content of meals affects postprandial responses, but the effects are small and depend on meal size or composition.

Adult↗
PubMed1993

Resting metabolic rate and diet-induced thermogenesis: a methodological reappraisal.

The variability in resting metabolic rate (RMR), diet-induced thermogenesis (DIT), and fuel utilization rates as well as the impact of several factors on RMR and DIT were assessed in several studies with a total of 103 males and females. The intraindividual CV of RMR and respiratory quotients was 5-6%. The intraindividual variability in DIT and fuel utilization rates was substantially higher. RMR did not change from morning to afternoon. The menstrual cycle phase did not affect RMR and DIT. DIT after mixed meals of 1.3-2.6 MJ could be assessed with good accuracy in 3 h. It is concluded that the low reproducibility of DIT implies that sample sizes of < 10 individuals with one measurement per subject and per treatment have power levels < 80% of assessing true, relatively large (50%) treatment effects or between-group differences in DIT.

Adult↗
PubMed1993

Visceral fat loss measured by magnetic resonance imaging in relation to changes in serum lipid levels of obese men and women.

The effect of weight reduction on serum lipids in relation to visceral fat accumulation was studied in 78 healthy obese subjects (40 premenopausal women and 38 men) aged 27-51 years and with an initial body mass index of 30.7 +/- 2.2 kg/m2 (mean +/- SD). The subjects received a 4.2 MJ/day energy-deficit diet for 13 weeks. Magnetic resonance imaging was used to assess abdominal fat areas before and after weight loss. Weight reductions of 12.6 +/- 3.2 kg in men and 11.7 +/- 3.8 kg in women resulted in larger reductions in the fasting serum levels of total cholesterol (p < 0.05), low density lipoprotein cholesterol (p = 0.06), and triglycerides (p < 0.01) and a larger increase in the high density lipoprotein cholesterol/low density lipoprotein cholesterol ratio (p = 0.05) in men compared with women. Men also lost more visceral fat (p < 0.0001), whereas the reductions in the total and subcutaneous abdominal fat depots were similar. In women, visceral fat loss was significantly related with an increase of the high density lipoprotein cholesterol level, independent of the degree of total fat loss. In men, however, no significant correlations were observed between changes in visceral fat and any of the serum lipids. Comparisons of average changes in obese men and women suggest that visceral fat loss is associated with an improvement of the serum lipid profile. However, correlation analysis does not support a critical role of visceral fat in determining serum lipid concentrations on an individual level, except for an improvement of the high density lipoprotein cholesterol level with visceral fat loss in obese women.

Adipose Tissue↗
PubMed1993

Relative effects of weight loss and dietary fat modification on serum lipid levels in the dietary treatment of obesity.

The independent effects of weight loss and dietary fat modification on serum lipids were investigated in two groups of healthy moderately obese men and women. In one group (sequential group, n = 19), a weight-stable low-fat, low-saturated-fat diet (Low-Sat) was given for 7 weeks (= dietary modification), followed by a 4.2 MJ/day deficit Low-Sat diet for 13 weeks (i.e., weight loss alone). Another group (simultaneous group, n = 22) received a 4.2 MJ/day deficit Low-Sat diet for 13 weeks (i.e., weight loss+dietary fat modification). Each group was subject to an initial weight-stable high-fat, high-saturated fat diet for 3 weeks and a final weight stable Low-Sat diet for 3 weeks. Both groups lost similar amounts of body weight, about 13 kg, and had similar overall changes in total cholesterol, low density lipoprotein (LDL), cholesterol, high density lipoprotein (HDL) cholesterol, the HDL/LDL ratio, and triglycerides. Analysis of the separate effects of the Low-Sat diet without energy restriction and of weight loss in the sequential group showed that weight loss per se was responsible for about 50% of the total reduction in total cholesterol, and for about 60% and 70% of the fall in LDL cholesterol and triglycerides, respectively. Fat modification without weight loss reduced HDL cholesterol by 11.1% and the HDL/LDL ratio by 7.7%, while weight loss per se led to increases in HDL cholesterol of 12.5% and in the HDL/LDL ratio of 24.0%. We conclude that the effects of reduction in fat and saturated fat intake and weight loss are additive.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Short-term effects of different amounts of protein, fats, and carbohydrates on satiety.

This study investigated the satiating efficiencies of proteins, fats, and carbohydrates (CHOs). Twenty-nine female, normal-weight subjects each received 10 liquid breakfasts, which varied in energy and macronutrient contents. Besides a zero condition [0.3 MJ (8 kcal)], there were three energy levels [0.42, 1.05, and 1.67 MJ (100, 250, and 400 kcal)] combined with three dominant sources of macronutrients (99% of energy from CHO, 92% of energy from fat, and 77% of energy from protein). After breakfast the subjects were not allowed to eat or drink (except water) for 3.5 h. They then recorded their voluntary food intake for the remainder of the day. Subjects also rated their subjective feelings concerning food intake on five different types of appetite. The results showed that neither energy content nor macronutrient composition of the liquid breakfasts had any effect on energy and macronutrient intake during lunch and the remainder of the day. Ratings of different types of appetite showed an increasing satiating effect with increasing energy content of the breakfasts. Proteins, fats, and CHOs had similar effects on appetite.

Adult↗
PubMed1992

Amylose-amylopectin ratio in a meal affects postprandial variables in male volunteers.

To study the postprandial effects of changing the amylose-to-amylopectin ratio (Am:Ap) in the starch fraction of a meal, male volunteers were given hot mixed lunches (13% of energy as protein, 24% as fat, 6% as mono- and disaccharides, and 57% as polysaccharides) in which Am:Ap was either 0:100 or 45:55. The increase in Am:Ap resulted in a change in the shape of the glucose and insulin responses in the blood with significantly lower initial responses but a small increase for glucose and a decrease for insulin if averaged over the 6 h of the study. The rises in the concentration of free glycerol and free fatty acid that occurred after an initial drop were stronger at low Am:Ap. High-Am:Ap meals induced more satiety up to 6 h postprandially. There was no effect of Am:Ap on postprandial triacylglycerol in the blood or on breath hydrogen except for a weak trend toward a higher concentration at 6 h after the high-Am:Ap meals.

Adult↗
PubMed1992

Visceral fat accumulation in obese subjects: relation to energy expenditure and response to weight loss.

Seventy-eight healthy obese subjects, 40 premenopausal women and 38 men aged 27-51 yr received a 4.2 MJ/day energy-deficit diet for 13 wk. Resting metabolic rate (RMR) and diet-induced thermogenesis (DIT) were measured by indirect calorimetry. Abdominal subcutaneous and visceral fat areas were calculated from magnetic resonance imaging scans before and after weight loss. Before weight loss, visceral fat accumulation was positively correlated with higher levels of RMR (P < 0.05) and DIT (P < 0.01) in women but not in men. The mean weight reduction was 12.2 +/- 3.5 (SD) kg. In men but not in women, an initially large visceral fat depot was associated with a reduced loss of weight and total fat mass (P < 0.05). Within each sex, an initial abundance of visceral fat was significantly related to a larger loss of visceral fat (P < 0.001) and in men to a smaller loss of subcutaneous fat (P < 0.05). These results suggest that there may be gender differences in the associations between visceral fat accumulation and components of energy expenditure (RMR and DIT) in obese subjects. Obese subjects with an initial abundance of visceral fat do not lose more body weight but more visceral fat than subjects with less visceral fat.

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↗
PubMed1990

Resting energy expenditure in women: impact of obesity and body-fat distribution.

Postabsorptive resting metabolic rate (RMR) and diet-induced thermogenesis (DIT) were repeatedly assessed with an indirect calorimetric ventilated hood system in a group of 32 healthy premenopausal obese women, body fat percentage 46.4 +/- 0.9 (mean +/- SEM), age 38.5 +/- 0.9 years. RMR and DIT were also measured in a group of 10 healthy premenopausal non-obese women, body fat percentage 31.3 +/- 1.7, age 37.7 +/- 2.4 years. The obese women were subdivided according to the waist-to-hips girth ratio (WHR) into three groups with a different type of body fat distribution: A gluteal-femoral obese group (n = 10), WHR less than 0.79; an intermediate obese group (n = 10), 0.79 less than WHR less than 0.85; and an abdominal obese group (n = 12), WHR greater than 0.85. No significant differences were observed among the obese groups in age, body weight, body fat mass, and fat-free body mass. Body fat distribution was not associated with differences in DIT, pre- and postprandial respiratory quotients and substrate oxidation rates, but the abdominal obese women had significantly higher RMRs adjusted for age, fat mass, and fat-free body mass (6,075 +/- 200 kJ/d) in comparison with the gluteal-femoral obese women (5,502 +/- 205 kJ/d) and in comparison with obese women with an intermediate body fat distribution (5,517 +/- 193 kJ/d), but not in comparison with a non-obese control group, 6,790 +/- 261 kJ/d. It is concluded that within the total group of obese women, the non-abdominal obese can be characterized by relatively reduced resting metabolic rates in comparison with either the abdominal obese or with non-obese women.

Adipose Tissue↗