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Biomedical subjects

A Astrup

Publications and source records attributed to A Astrup.

At least 91 records · Page 5Linked to original sources
PubMed1999

Randomized trial on protein vs carbohydrate in ad libitum fat reduced diet for the treatment of obesity.

OBJECTIVE: To study the effect on weight loss in obese subjects by replacement of carbohydrate by protein in ad libitum consumed fat-reduced diets. DESIGN: Randomized dietary intervention study over six months comparing two ad libitum fat reduced diets (30% of total energy) strictly controlled in composition: High-carbohydrate (HC, protein 12% of total energy) or high-protein (HP, protein 25% of total energy). SETTING AND PARTICIPANTS: Subjects were 65 healthy, overweight and obese subjects (50 women, 15 men, aged 18-55 y) randomly assigned to HC (n = 25), HP (n = 25) or a control group (C, n = 15). All food was provided by self-selection in a shop at the department, and compliance to the diet composition was evaluated by urinary nitrogen excretion. MAIN OUTCOME MEASURE: Change in body weight, body composition and blood lipids. RESULTS: More than 90% completed the trial. Weight loss after six months was 5.1 kg in the HC group and 8.9 kg in the HP group (difference 3.7 kg, 95% confidence interval (CI)(1.3-6.2 kg) P < 0.001), and fat loss was 4.3 kg and 7.6 kg, respectively (difference 3.3 kg (1.1-5.5 kg) P < 0.0001), whereas no changes occurred in the control group. More subjects lost > 10 kg in the HP group (35%) than in the HC group (9%). The HP diet only decreased fasting plasma triglycerides and free fatty acids significantly. CONCLUSIONS: Replacement of some dietary carbohydrate by protein in an ad libitum fat-reduced diet, improves weight loss and increases the proportion of subjects achieving a clinically relevant weight loss. More freedom to choose between protein-rich and complex carbohydrate-rich foods may allow obese subjects to choose more lean meat and dairy products, and hence improve adherence to low-fat diets in weight reduction programs.

Adolescent↗
PubMed1999

Obese male subjects show increased resting forearm venous plasma noradrenaline concentration but decreased 24-hour sympathetic activity as evaluated by thrombocyte noradrenaline measurements.

OBJECTIVE: To study resting forearm venous plasma noradrenaline (NA) and 24 h sympathoadrenal activity evaluated by measurements of thrombocyte NA and adrenaline (A) in obese male subjects before and after weight reduction. DESIGN: Blood samples were collected in obese subjects and in controls after an overnight fast. MEASUREMENTS: Fatness and fat distribution parameters, plasma and thrombocyte NA and A, lymphocyte beta 2-adrenoceptor mRNA, cAMP and lymphocyte subset composition. RESULTS: Forearm venous plasma NA at rest was significantly elevated in the obese subjects and correlated to the body mass index and diastolic blood pressure. Thrombocyte NA and A correlated, however, negatively to the body fat % in obese subjects. Further analysis showed that thrombocyte NA and A were reduced in obese subjects with body fat % above 40% but not in the other groups. Weight reduction normalized both forearm venous plasma NA and thrombocyte NA and A. beta 2-adrenoceptor mRNA correlated positively to the frequency of CD3-CD56+ and CD3+CD8+ cells in the blood and negatively to plasma A, but there was no difference in the mRNA level, cyclic AMP and lymphocyte subset composition between obese and controls. CONCLUSIONS: Sympathetic activity at rest as evaluated by forearm venous plasma NA was increased in the obese male subjects and this abnormality was related to the increase in body mass index and the arterial blood pressure. Thrombocyte NA and A, which is likely to reflect 24 h plasma catecholamine concentrations were reduced in obese subjects with a body fat % above 40%, probably due to a reduced physical activity in these subjects. Both catecholamine parameters were normalized by weight reduction.

Adolescent↗
PubMed1999

Impact of the v/v 55 polymorphism of the uncoupling protein 2 gene on 24-h energy expenditure and substrate oxidation.

OBJECTIVE: The gene that codes for a novel uncoupling protein, UCP2, has been linked to obesity in animal models. Markers encompassing the UCP2 locus have been linked to energy expenditure in humans. We studied the role of a common amino acid substitution, replacing an alanine (A) with a valine (V) at codon 55, of the coding region of the UCP2 gene for 24-h energy expenditure and respiratory quotient (RQ) in healthy subjects METHODS: 24-h energy expenditure and RQ were measured in calorimeters in 60 healthy subjects. The UCP2 polymorphism was determined by restriction fragment length polymorphism-generating polymerase chain reaction. RESULTS: Age, gender and body fat were not different between groups, the number of subjects in each groups was A/A: 35% (n=21), A/V: 48% (n=29), and V/V: 17% (n=10). Twenty-four-hour energy expenditure, adjusted for fat-free mass, fat mass, and spontaneous physical activity, was 311 kJ/d lower (95% confidence interval: 24-598 kJ/d, P=0.03) in the V/V homozygotes than in the A/A and A/V genotypes. The V/V had approximately 20% higher 24-h spontaneous physical activity, particularly higher at night (P<0.005). Energy expenditure due to higher spontaneous physical activity counteracted the V/V group's lower 24-h resting energy expenditure for a given body size and composition. 24-h RQ adjusted for energy balance, age, sex and spontaneous physical activity, was higher in the V/V homozygotes than in the AA and A /V groups (P<0.05). CONCLUSIONS: Subjects with the V/V genotype of the UCP2 gene exhibit an enhanced metabolic efficiency and lower fat oxidation than the A/A and A/V genotypes.

Adult↗
PubMed1999

Changes in renal function during weight loss induced by high vs low-protein low-fat diets in overweight subjects.

BACKGROUND: Due to the high satiating effect of protein, a high-protein diet may be desirable in the treatment of obesity. However the long-term effect of different levels of protein intake on renal function is unclear. OBJECTIVE: To assess the renal effects of high vs low protein contents in fat-reduced diets. DESIGN: Randomized 6 months dietary intervention study comparing two controlled ad libitum diets with 30 energy (E%) fat content: high-protein (HP; 25 E%) or low-protein, (LP, 12 E% protein). All food was provided by self-selection in a shop at the department, and high compliance to the diet composition was confirmed by measurements of urinary nitrogen excretion. SUBJECTS: 65 healthy, overweight and obese (25<body mass index (BMI)<34 kg/m2). RESULTS: Dietary protein intake changed from 91.1 g/d to a 6 months intervention average of 70.4 g/d (P<0.05) in the LP group and from 91.4 g/d to 107.8 g/d (P<0.05) in the HP group, producing changes in glomerular filtration rate (GFR) of -7.1 ml/min in the LP group and +5. 2 ml/min in the HP group (group effect: P<0.05). Kidney volume decreased by -6.2 cm3 in the LP group and increased by +9.1 cm3 in the HP group (P<0.05), whereas albuminuria remained unchanged in all groups. CONCLUSION: Moderate changes in dietary protein intake cause adaptive alterations in renal size and function without indications of adverse effects.

Adolescent↗
PubMed1999

The effect of sibutramine on energy expenditure and appetite during chronic treatment without dietary restriction.

OBJECTIVE: To assess the contribution of a thermogenic effect to weight loss induced by eight weeks treatment with sibutramine (15mg/d) vs placebo in obese subjects. DESIGN: Randomised, placebo controlled, double blind study. SUBJECTS: Thirty-two (7 male, 25 female) healthy obese body mass index (BMI) 33.9+/-0.5 kg/m2 subjects completed the trial. MEASUREMENTS: Energy expenditure (EE) was measured by indirect calorimetry during a 32 h stay in a respiration chamber before and after 8 weeks treatment. Visual analogue scales were completed for assessment of appetite sensation. No dietary restriction was given. RESULTS: Sibutramine caused a significant weight loss compared with placebo (-2.4 kg vs+0.3 kg, P<0.001). Despite the larger weight loss after 8 weeks, 24-h EE did not decrease more in the sibutramine than in the placebo group (-2. 6% vs -2.5%, P=ns). When the changes in 24-h EE were adjusted for changes in body weight, 24-h EE decreased significantly less in the sibutramine group than in the placebo group (0.8% vs 3.8%, P<0.02). Sibutramine significantly decreased both hunger and anticipated food consumption, and increased satiety scores. CONCLUSIONS: The weight reducing effect of sibutramine in humans is caused by a dual mechanism: reduction of energy intake by increasing satiety and decreasing hunger and prevention of the decline in EE that follows weight loss.

Adult↗
PubMed1999

Increased intensity of a single exercise bout stimulates subsequent fat intake.

BACKGROUND: The physical activity pattern in society has in recent years changed from necessary occupational activity to voluntary activities during leisure-time. How this change in lifestyle affects the selection of dietary intakes is presently unknown. OBJECTIVES: The aim of the present study was to investigate the different effects of high vs. low-intensity exercise on the following day's dietary energy intake and macronutrient selection. DESIGN: The study was designed as a controlled randomized cross-over study which compared food selection and energy intake the day following a low-intensity vs a high-intensity exercise bout. We included 32 healthy normal-weight subjects of four subgroups (young males, young females, old males and old females). On two different occasions they performed either 60 min low-intensity (30% of VO2max) or 30 min high-intensity (60% of VO2max) exercise during 24h measurements of energy expenditure. The energy intake and macronutrient selection of the subsequent day was assessed by offering them an adlibitum buffet at breakfast and at lunch. RESULTS: Following the low-intensity exercise the subjects chose a diet with an energy percentage from fat similar to that of their habitual diet-36.7% (95% CI: 34.3, 39.0) vs 35.6% (95% CI: 33.0, 38.2; NS). Following the high-intensity exercise they chose a diet with 39.9% (95% CI: 37.2, 42.6) fat, which was 3.2% (95% CI: 0.6, 5.9) higher than following the low-intensity exercise (P<0.05) and 4.2% (95% CI: 1.1, 7.4) more than their habitual diet (P<0.01). CONCLUSIONS: The present study shows that changing the type of activity of a single exercise bout from 30% of maximal aerobic capacity for 60 min to 60% for only 30 min resulted in consumption of a diet the following day with a higher fat energy percentage compared with the diet selected after the low-intensity exercise. However, the higher fat content diet did not result in a higher energy intake.

Adult↗
PubMed1999

Comparison of resting energy expenditure measurements by ventilated canopy and by respiration chamber.

The study compared measurements of resting energy expenditure (REE) by two methods, namely the commercially available ventilated canopy (Medgraphics CCM system) and the respiration chamber. Thirty-five healthy subjects of both sexes with a wide weight range (BMI 18-33.8 kg m-2) were measured on both systems. The linear regression equation was REEcanopy = 0.66 x REEresp.cham. + 61.1 (kJ h-1), and the corresponding SEE% was 8.6%. The correlation was high (r = 0.89). However, the mean REE measured using the ventilated canopy was 41 kJ h-1 (13%) lower than that using the respiration chamber (P < 0.01). The Medgraphics CCM canopy system seems valid for measurements of REE. However, the REE results measured by the canopy were systematically lower than when measured by the respiration chamber, but can be converted by the equation given with an accuracy error of 9%.

Adult↗
PubMed1999

Dietary approaches to reducing body weight.

Diet is one of the cornerstones of a weight loss programme. Although there is little evidence that diet composition plays a clinically important role in the absorption or expenditure of energy, it does appear to play a role in food intake. Diets with a deficit of 500-1000 kcal per day will produce weight losses of between 300 and 1000 g per week, depending on the patient's weight. Formulae for estimating energy intake are provided. Starvation diets with an energy intake below 200 kcal per day are no longer used, but very low-energy diets with an energy intake of between 200 and 800 kcal per day have been used, although there is little to support the use of energy levels below 800 kcal per day. Ad libitum low-fat diets have been reported to produce weight losses that average 1.6 g per day for each 1% reduction in the level of fat. In a meta-analysis, overweight subjects lost 5-7 kg before reaching a new plateau. In normal weight subjects, the loss was only 0.5 kg. A low-fat diet may be of value in helping patients to maintain their weight loss. Higher-protein diets were more effective than low-protein diets in one clinical trial. The type of carbohydrate in the low-fat diet does not appear to influence weight loss. Alcohol, on the other hand, is poorly satiating and may replace fat in oxidative processes, thus enhancing the risk of obesity.

Animals↗
PubMed1999

Meta-analysis of resting metabolic rate in formerly obese subjects.

BACKGROUND: A low resting metabolic rate (RMR) for a given body size and composition is partly genetically determined and has been suggested to be a risk factor for weight gain. Moreover, a low relative RMR has been reported in some, but not all, studies of formerly obese persons. The inconsistent reports may be due to a lack of statistical power to detect small differences in RMR and improper adjustment for body size and composition. OBJECTIVE: We conducted a meta-analysis based on published studies of RMR in formerly obese persons [body mass index (in kg/m2) < or = 27] and matched control subjects who had never been obese. DESIGN: We performed both an individual subject data meta-analysis and a traditional meta-analysis. RESULTS: The individual subject data meta-analysis included 124 formerly obese and 121 control subjects. RMR adjusted for differences in fat-free mass and fat mass was 2.9% lower in formerly obese subjects than in control subjects (P = 0.09). A low relative RMR (> 1 SD below the mean of the control group) was found in 3.3% of the control subjects and in 15.3% of the formerly obese subjects [difference: 12% (95% CI: 4.7%, 19.3%); P < 0.003]. The traditional meta-analysis was based on 12 studies (including 94 formerly obese and 99 control subjects) and included 3 studies not represented in the individual subject data analysis. In this analysis, relative RMR was lower in the formerly obese group than in the control group by 5.1% (95% CI: 1.7%, 8.6%). CONCLUSIONS: Formerly obese subjects had a 3-5% lower mean relative RMR than control subjects; the difference could be explained by a low RMR being more frequent among the formerly obese subjects than among the control subjects. Whether the cause of the low RMR is genetic or acquired, the existence of a low RMR is likely to contribute to the high rate of weight regain in formerly obese persons.

Basal Metabolism↗
PubMed1999

Physical activity and weight gain and fat distribution changes with menopause: current evidence and research issues.

PURPOSE: At the onset of menopause a woman's body weight reaches its maximum. For any given subsequent body weight there is an increase in relative body fat and abdominal fatness with advancing age. The increased body fatness and abdominal fat distribution are associated with a high incidence of cardiovascular disease and certain cancers, particularly breast cancer. The aim of this analysis was to assess the role of physical activity for weight gain and changes in fat distribution occurring with menopause. METHODS: A systematic review based on a Medline search was conducted. RESULTS: According to cross-sectional observational studies postmenopausal women with high levels of physical activity have lower body fat and abdominal fat. Longitudinal studies show that physically active women are less likely to gain body fat and abdominal fat after menopause than sedentary women (Evidence category C). There are very few randomized controlled trials (RCT) comparing exercise with no intervention, and diet with diet plus exercise, and the results do not allow a firm conclusion as to whether physical activity may prevent or limit the gain of total fat and abdominal fat after menopause, or whether it may be effective as part of an obesity treatment program. CONCLUSIONS: There is a need for RCT to evaluate the effect of increased physical activity and fitness as a tool for prevention of the changes in body composition associated with menopause and aging in normal weight women. The efficiency of different programs of exercise training as a treatment option in postmenopausal women with existing overweight and obesity should be investigated. RCT should have the appropriate design and size and use accurate methods to assess exercise compliance, body composition, and intra-abdominal adipose tissue.

Abdomen↗
PubMed1998

Glucagon-like peptide 1 promotes satiety and suppresses energy intake in humans.

We examined the effect of intravenously infused glucagon-like peptide 1 (GLP-1) on subjective appetite sensations after an energy-fixed breakfast, and on spontaneous energy intake at an ad libitum lunch. 20 young, healthy, normal-weight men participated in a placebo-controlled, randomized, blinded, crossover study. Infusion (GLP-1, 50 pmol/ kg.h or saline) was started simultaneously with initiation of the test meals. Visual analogue scales were used to assess appetite sensations throughout the experiment and the palatability of the test meals. Blood was sampled throughout the day for analysis of plasma hormone and substrate levels. After the energy-fixed breakfast, GLP-1 infusion enhanced satiety and fullness compared with placebo (treatment effect: P < 0.03). Furthermore, spontaneous energy intake at the ad libitum lunch was reduced by 12% by GLP-1 infusion compared with saline (P = 0.002). Plasma GLP-1, insulin, glucagon, and blood glucose profiles were affected significantly by the treatment (P < 0.002). In conclusion, the results show that GLP-1 enhanced satiety and reduced energy intake and thus may play a physiological regulatory role in controlling appetite and energy intake in humans.

Adult↗
PubMed1998

Sustained improvement in blood lipids, coagulation, and fibrinolysis after major weight loss in obese subjects.

OBJECTIVE: To study whether major weight loss causes sustained improvement in blood lipids and haemostatic profile in obese subjects, and to compare the influence of two different slimming and maintenance regimens. DESIGN: Two-stranded randomized intervention study. SETTING: University Department. SUBJECTS: Thirty-six out of 43 obese patients recruited from out-patient waiting list completed the study. INTERVENTIONS: Weight loss was achieved by very low energy formula diet (2 MJ/d for 8 weeks, n=18), or low-energy conventional diet (5 MJ/d for 17 weeks, n=18), both combined with anorectic compound. Participants were re-randomized to consume low fat diet ad libitum (n=16), or energy-restricted diet (n=20) for weight maintenance during 24 weeks. MAIN OUTCOME MEASURES: Plasma lipids, fibrinogen, factor VII coagulant activity (FVIIc), and plasminogen activator inhibitor type 1 (PAI-1) antigen. RESULTS: Weight loss averaged 13.6 kg (95% CI: 12.3-14.9 kg). After 24 weeks' weight maintenance, plasma total cholesterol was 9% lower, high density lipoprotein cholesterol 5% higher, triglycerides 30% lower, FVIIc 12% lower, fibrinogen 6% lower, and PAI-1 antigen 34% lower than at baseline (all changes highly significant). There were no significant differences between slimming or maintenance regimens. CONCLUSIONS: Major weight loss is associated with sustained and marked improvements in blood lipids and hemostatic profile, irrespective of the tested slimming and maintenance regimens.

Adult↗
PubMed1998

Substrate oxidation and thyroid hormone response to the introduction of a high fat diet in formerly obese women.

OBJECTIVE: To investigate the adaptation in substrate utilization to a sudden change in dietary composition from a medium fat to a high fat diet, during a three day period in formerly obese and never obese women. METHODS: Energy expenditure (EE) and substrate oxidation rates were measured in eight healthy formerly obese women and eight never obese controls, during four consecutive days in a respiration chamber. The first day and the day prior to the experiment, the subjects consumed a diet with 30 energy-% fat, whereas the diet had 55 energy-% fat on the subsequent three days. RESULTS: The rate of adjustment of oxidative substrate partitioning expressed as 24 h non-protein respiratory quotient (RQnp) was similar in the two groups. RQnp on each of the days was also similar between the two groups, after accounting for a group difference in energy balance, caused by a non-significantly lower EE in the formerly obese women. However, the formerly obese subjects, demonstrated a greater suppression of postprandial fat oxidation after supper, which was unrelated to energy balance. Furthermore, the formerly obese subjects, in contrast to the controls, exhibited a reduction in plasma triiodothyronine/thyroxine ratio (T3/T4) following the high fat diet. A positive correlation between T3/T4 and EE was found in the 16 subjects. CONCLUSIONS: The formerly obese subjects did not show a slower adaptation rate of substrate utilization when challenged with a high fat diet, but exhibited an enhanced suppression of fat oxidation and a lower T3/T4 ratio after supper, when fed a high fat diet.

Adult↗
PubMed1998

What do pharmacological approaches to obesity management offer? Linking pharmacological mechanisms of obesity management agents to clinical practice.

Obesity is characterised by pathophysiological defects affecting both sides of the energy balance equation. Individuals with a predisposition to obesity have impaired appetite control when diets are fat-rich and energy dense. They also exhibit a lower than expected resting metabolic rate (RMR). A low RMR, in concert with a sedentary lifestyle, contributes to a low total energy output, which may lead to obesity if continued over a period of years. A low metabolic rate seems to be genetically determined, and is partly caused by low sympathetic nervous system activity. Classical treatment programmes for obesity do not provide a satisfactory long-term outcome for the majority of patients. Patients who achieve only a small weight loss during dietary therapy, and have a tendency to weight regain, are characterised by lower energy expenditure, lower sympathetic activity, and a reduced ability to mobilise fat stores, compared with patients who are more successful at losing weight. It is reasonable to improve or normalise these traits by supporting the dietary approach with pharmacological manipulation of central and peripheral pathways. Agents which stimulate adrenergic neurons are particularly suitable because they offer mechanisms for inhibiting hunger and for stimulating energy expenditure, lipolysis and fat oxidation. Sympathomimetic compounds can reduce appetite and increase energy expenditure. Energy expenditure can be increased by 5-10% via stimulation of a combination of beta-adrenoceptors; beta3-adrenoceptors may predominate during chronic therapy. This increased energy expenditure increases the relative proportion of fat oxidation; as this is not fully compensated by increased energy intake, a negative energy balance occurs. This mechanism may be responsible for the long-term weight loss efficiency of agents like ephedrine/caffeine and sibutramine. Pharmacotherapy can be used to support short-term induction of weight loss or long-term weight maintenance. In the latter case, adrenergic agents enable a greater proportion of patients to maintain a satisfactory weight loss, compared with patients treated with conventional programmes alone. Pharmacotherapy which stabilises the size of fat stores at a lower level contributes indirectly to a pronounced improvement of risk factors, leading to a decreased potential for cardiovascular disease, type 2 diabetes and associated morbidity.

Adrenergic beta-Agonists↗
PubMed1998

Thermogenic effects of sibutramine in humans.

BACKGROUND: Sibutramine is an effective compound for the treatment of obesity, acting both on serotonergic and noradrenergic pathways. Animal studies have shown that sibutramine exerts its effect by enhancing satiety as well as by increasing thermogenesis. OBJECTIVE: We tried to compare the acute thermogenic effect of a single 30-mg dose of sibutramine with placebo on basal energy expenditure (EE) and diet-induced thermogenesis. DESIGN: The study was randomized, double-blind, and placebo controlled. Eleven healthy, normal-weight men underwent 4 distinct treatment regimens separated by washout periods of 6-10 d. EE was measured by indirect calorimetry before and for 5.5 h after sibutramine or placebo administration with or without a 2.1-MJ breakfast. Visual analogue scales for assessment of appetite were completed hourly. RESULTS: Sibutramine caused a significant increase in EE above that for placebo (over 5.5 h) during both the fed (34%, 0.15 kJ/min) and fasted (183%, 0.20 kJ/min) states (P < 0.02) as well as during the last 3.5 h of this 5.5-h period and in the fed (87%, 0.26 kJ/min) and fasted (152%, 0.22 kJ/min) states, respectively (P < 0.01). The sibutramine-induced increase in EE was accompanied by an increase in plasma epinephrine (P < 0.01), heart rate (P < 0.001), blood pressure (P < 0.05), and plasma glucose (P < 0.02). About 25% of the increased heart rate with sibutramine could be explained by increased thermogenesis. Sibutramine increased satiety more than did placebo (5-h area under the curve, P < 0.05). CONCLUSIONS: Sibutramine caused a significant increase in both EE and satiety, which may both contribute to its weight-reducing properties.

Adult↗
PubMed1998

D-Tagatose, a stereoisomer of D-fructose, increases hydrogen production in humans without affecting 24-hour energy expenditure or respiratory exchange ratio.

In growth studies on rats, the ketohexose D-tagatose has been shown to contribute no net metabolizable energy, and a pronounced thermic effect of the sugar has been suggested to account for the absence of energy. In a double-blind and balanced cross-over design, we measured 24-h energy expenditure in eight normal weight humans in a respiration chamber during the consumption of 30 g D-tagatose or 30 g sucrose/d. Metabolic measurements were performed before and after a 2-wk adaptation period with a 30-g daily intake of the test sugar. Total 24-h energy expenditure and hour-by-hour profile were unaffected by the test sugar. The nonprotein respiratory exchange ratio (RERnp) was similar during consumption of D-tagatose and sucrose. However, the effect on RERnp due to CO2 produced by fermentation of D-tagatose could not be quantified in this study. A significant increase in 24-h H2 production (35%) during D-tagatose administration suggests a substantial malabsorption of the sugar. We found no effects of the 2-wk adaptation period on the measured gas exchange variables. Significantly lower fasting plasma insulin and triglyceride concentrations were observed during D-tagatose administration compared with the sucrose period. No effects of D-tagatose on body weight and composition were seen, but the perception of fullness 2.5 h after the sugar load was greater with D-tagatose. In conclusion, this study does not suggest a pronounced thermic effect of D-tagatose, and other mechanisms seem to be required to explain its lack of net energy.

Adult↗
PubMed1998

The American paradox: the role of energy-dense fat-reduced food in the increasing prevalence of obesity.

Although surveys have reported that the fat content of the diet has decreased over past decades, the prevalence of obesity has continued to rise in Europe and North America. This phenomenon, 'the American paradox', has been attributed partly to an inability of the reduction in dietary fat to reduce excess body fat, and partly to the over-consumption of low-fat products, which, despite their reduced fat content, have in some cases been accused of maintaining a high energy density due to low fibre and water contents, and a high content of refined carbohydrates. In Denmark, the prevalence of obesity has increased in a period in which national dietary surveys have reported a reduction of more than 10% in dietary fat content. Analysing the Danish situation, it seems unlikely that the occurrence of the American paradox in Denmark is caused by the increased consumption of energy-dense, low-fat foods. Other explanations, e.g. the under-reporting of dietary fat in surveys and the clustering of obesity-promoting lifestyles in subgroups of the population, should be sought.

Denmark↗