Effects of weight loss on single meal eating behaviour in obese subjects

In 22 obese patients the eating pattern during a single meal as evaluated by the universal eating monitor VIKTOR was assessed after one year of treatment, initially with VLCD (Nutrilett) followed by combined long term diet, exercise and behavioural modification, underscoring the importance of appropriate meal habits. A mean weight loss from 117 to 101 kg was achieved. Before treatment a decelerated eating curve was found; after treatment this curve changed significantly towards a flatter and more linear shape.

Taste acuity in patients with chronic renal failure

Taste acuity for the four primary tastes has previously been shown to be impaired in patients with chronic renal failure (CRF) and maintenance dialysis treatment, although data on CAPD (continuous ambulatory peritoneal dialysis) patients are insufficient. In a test group of 57 CRF patients and 57 healthy controls, matched for age, sex and body mass index (BMI, kg/m2) taste acuity for the four primary tastes was determined. Fourteen patients were on CAPD treatment and 12 patients on hemodialysis (HD). No patients or controls were diabetic, on antibiotic treatment or had a malignant disease. Taste tests were standardized and performed on dialysis-free days for HD-patients. Taste acuity for bitter and salt was significantly lower for preuremic patients compared to their controls. In CAPD-patients taste detection of bitter was impaired and in HD-patients detection of salty taste was impaired. In conclusion taste acuity is impaired in uremic patients and dialysis patients including CAPD. The mechanism for taste alterations remain to be explained.

Long-term intervention strategies in obesity treatment

Obesity is a chronic condition, requiring long-term treatment. In addition to various combinations of diet, exercise and behavioural modifications, weight-reducing drugs will be useful in different situations. Weight loss expectations must be realistic. Drugs which control appetite, nutritional partitioning and thermogenesis may have various roles in different stages of the long-term treatment strategies. Combinations and intermittent regimens will probably result in optimal retained weight loss for the individual, but will be difficult to evaluate systematically.

Effects of weight reduction on the regulation of lipolysis in adipocytes of women with upper-body obesity

1. The regulation of lipolysis was studied in 14 upper-body obese women aged 26-55 years. Isolated subcutaneous adipocytes from the abdominal region were examined before and after an 8 to 12-week-long weight reduction programme, during which the mean body mass index (kg/m2) of the group was reduced from 36.4 +/- 0.9 to 30.3 +/- 1.0. 2. Fat cell volume was reduced from 891 +/- 39 to 655 +/- 45 pl. The sensitivity to noradrenaline stimulation of lipolysis in vitro increased fivefold after weight reduction. A corresponding increase in sensitivity was found with the beta 2-selective adrenoceptor agonist terbutaline. However, the number of beta 2-adrenoceptor binding sites as assessed by radioligand binding with 125I-labelled cyanopindolol was not changed. No changes were observed when dobutamine (a beta 1-selective adrenoceptor agonist) and clonidine (an alpha 2-adrenoceptor agonist) were used. 3. The basal lipolysis rates decreased by about 50% after weight reduction and the maximum enzyme activity of hormone-sensitive lipase was also reduced by almost 50%. 4. Plasma concentrations of insulin, noradrenaline and total testosterone decreased and sex hormone-binding globulin increased after weight reduction. Calculated apparent free testosterone levels decreased by more than 40% after weight reduction. 5. In conclusion, weight reduction leads to increased efficiency of adipocyte lipolysis with decreased resting lipolysis rate but increased sensitivity to stimulation by catecholamines, which may be attributed to a decreased activity of hormone-sensitive lipase and an increased sensitivity of beta 2-adrenoceptors. Changes in circulating levels of catecholamines, insulin and testosterone may play a role in these modifications of adipocyte function.(ABSTRACT TRUNCATED AT 250 WORDS)

Weight maintenance after a very low calorie diet (VLCD) weight reduction period and the effects of VLCD supplementation. A prospective, randomized, comparative, controlled long-term trial

OBJECTIVES

To evaluate the efficacy of a structured very low calorie diet (VLCD) weight reduction/weight maintenance behaviour programme on weight maintenance in obese patients (BMI > or = 30 kg/m2).

DESIGN

Prospective, randomized, controlled intervention trial.

SETTING

University out-patient obesity clinic.

SUBJECTS

A total of 114 obese patients from the waiting list were invited to participate in the structured weight reduction/weight maintenance programme lasting for 64 weeks. Sixty patients agreed to participate.

INTERVENTION

All 60 patients were placed on a Cambridge 330 kcal day-1 diet during the first 12 weeks. Fifty-two were subsequently randomized to either a well balanced hypocaloric diet (1600 kcal day-1), of which 220 kcal were provided by two sachets of Cambridge diet (group 1), or the same energy provided by the same principal diet (group 2) during the following 52-week weight maintenance period.

MAIN OUTCOME MEASURES

During the VLCD period, the mean body weight decreased significantly from 112.4 +/- 19.8 to 91.6 +/- 17.7 kg (P < 0.0001). Seventy-one per cent of the weight loss was fat. During the weight maintenance period the average body weight increased significantly in group 1: 8.0 +/- 8.2 vs. 12.3 +/- 9.7 kg in group 2 (P < 0.0001). After the 64-week treatment period the mean body weight in group 1 was 93.7 +/- 18.1 kg and significantly lower compared to 109.9 +/- 23.8 kg in group 2 (P = 0.008). Compliance was high: 87% completed the VLCD period and 75% completed the whole 64-week treatment programme.

CONCLUSION

Very low calorie diet as part of the dietary allowance during the weight maintenance programme partly prevents weight regain. This finding can be translated into practical treatment recommendations.

Pregnancy as a risk factor for obesity: lessons from the Stockholm Pregnancy and Weight Development Study

Pregnancy and maternal body weight development are intertwined in complicated patterns. In most studies, an increase in maternal body weight with age and parity has been reported. For women who develop obesity, pregnancies can, in retrospect, be identified as important triggering life events. In a retrospective analysis of 128 women at our Obesity Unit, 73% of these severely obese patients had retained more than 10 kg in connection with a pregnancy. For the general population, the effect of a pregnancy on future weight development is surprisingly difficult to predict. In The Stockholm Pregnancy and Weight Development Study, the effects of pregnancy on weight retention one year after delivery were studied in 1423 women. Data were collected retrospectively from routine pregnancy records and then extended prospectively 6 and 12 months after delivery. The mean weight retention associated with a pregnancy one year after delivery was estimated to about 0.5 kg, with a range of -12 to +26 kg. Fourteen percent of the women gained more than 5 kg. Weight increase during pregnancy was the strongest predictor for sustained weight retention 1 year later. Prepregnancy weight did not predict the weight development outcome. The lactation pattern had only a minor influence on weight development. Smoking cessation was an important predictor for sustained weight increase. More weight retention was observed in those women who reported a change in lifestyle as regarded eating habits, meal patterns, and physical activity, suggesting that eventual body weight after pregnancy is more determined by the changes in association with that particular pregnancy than with the lifestyle before.

Methodological studies on single meal food intake characteristics in normal weight and obese men and women

METHOD

The eating behaviour of 19 normal weight males, 19 obese males, 19 normal weight females and 19 obese females was measured by means of VIKTOR, our version of the universal eating monitor. The total food intake, the duration of consumption, the rate of consumption, the relative rate of consumption and the subjective motivation to eat were measured during five homogenous lunch meals to analyse how these variables were related to body weight or to sex. Furthermore, the stability of the eating characteristics over the five eating occasions were tested with pre-defined criteria of stability. The predictive validity of the variables measuring subjective motivation to eat and forthcoming food intake was also tested.

RESULTS

Men ate more food than women; normal weight men by eating for a longer time and obese men by eating faster. Females did not slow down the eating rate towards the end of the meals as much as males did. The obese subjects described themselves as having less motivation to eat prior to meals than normal weight subjects.

CONCLUSIONS

Total stability, i.e. both relative and absolute stability, for all subjects was present for the eating variables intake of food and eating rate. Of the variables measuring subjective motivation to eat (desire to eat, hunger, fullness and prospective consumption) on visual analogue scales, only the variables desire to eat and prospective consumption predicted forthcoming food intake.

Effects of smoking and physical activity on body weight: developments in Sweden between 1980 and 1989

OBJECTIVES

To study the effects of changes in smoking and exercise habits on body weighty in Sweden.

DESIGN

Analysis of factors affecting relative body weight by construction of regression equations using two models: one adjusted for age, education, socioeconomic group, geographical region and nationality, the other further adjusted for cigarette smoking and leisure-time physical activity.

SETTING

Cross-sectional interview data derived from the Undersökning om LevnadsFŏrhållanden' (Living Conditions) survey 1980-81 and 1989-89.

SUBJECTS

Nationally representative samples of Swedish men and women aged 16-84.

MAIN OUTCOME MEASURES

Changes in body-mass index (BMI) in Sweden during the 1980s.

RESULTS

Using the first model, an increase in the BMI of 0.23 kg/m2 in men and 0.17 kg/m2 in women, from 1980 to 1989, was found. When controlling for smoking and physical activity, these values were 0.20 and 0.18 kg/m2, respectively. (P at least < 0.003).

CONCLUSIONS

These findings indicate that the reported decrease in smoking and changes in physical activity during the 1980s only marginally explain the BMI increase in the adult Swedish population. The health programmes launched during the 1980s seem to have little beneficial effects on body-weight development, in particular in younger generations of both sexes.

Intravenous enterostatin does not affect single meal food intake in man

Enterostatin, a pentapeptide released with colipase from pancreatic procolipase in man, affects eating behaviour in animals. We report the first phase II study of intravenous (i.v.) enterostatin (D3800) in obese but otherwise healthy men. Eighteen men (mean age 37 years, mean body mass index 34.9 kg/m2) completed a double-blind, randomized, crossover placebo controlled trial. After in initial session, each man received i.v. 4 mg D3800, 16 mg D3800 or placebo in random order over three sessions, immediately before a test meal served on a universal eating monitor. No statistically significant effect of i.v. enterostatin on any uptake or rating variable was observed. Several factors may explain the lack of effect, e.g. the inability of i.v. enterostatin to reach a site of action, the time between i.v. administration and eating, and the possibility that the only human responders are those who express particular fat preferences.

Effects of weight reduction programs on close family members

Ninety-two patients in long-term treatment for obesity completed a questionnaire on the weight development of their close family members. Of 47 such relatives, 37 had lost a mean of 6.1 kg and 10 increased a mean of 5.1 kg. Treatment of obesity will affect many more than those taking part in the actual program and generally result in weight loss. This effect on family members was mostly considered beneficial.

Catecholamine resistance in fat cells of women with upper-body obesity due to decreased expression of beta 2-adrenoceptors

Upper-body obesity is an important risk factor for developing non-insulin dependent diabetes. To investigate the possibility that a lipolysis defect is present in this form of obesity, we examined the adrenergic regulation of lipolysis in abdominal subcutaneous fat cells from 25 women with upper-body obesity and 24 non-obese women. Lipolytic noradrenaline sensitivity (but not the maximum rate of lipolysis) was reduced by 10-fold in obese women (p < 0.01). The noradrenaline resistance could be ascribed to a 10-fold decrease in lipolytic beta 2-adrenoceptor sensitivity (p < 0.01). The lipolytic sensitivity of beta 1- and alpha 2-adrenergic receptors was normal in the obese women. A 70% reduction in the cell surface density of beta 2-adrenoceptors was observed compared to the control subjects (p < 0.01). However, beta 1-receptor density as well as steady-state mRNA levels for beta 1- and beta 2-receptors were normal in obese women. Lipolytic noradrenaline sensitivity correlated inversely with BMI (adjusted r2 = 0.76 together with fat cell volume in stepwise regression analysis). The fasting plasma level of free cortisol was 30% lower in obese compared to non-obese women (p < 0.05) but obesity did not influence resting plasma catecholamine levels. Thus, lipolytic catecholamine resistance is present in abdominal obesity, due to low density of beta 2-adrenoceptors, which in its turn may be caused by a post-transcriptional defect in beta 2-receptor expression.(ABSTRACT TRUNCATED AT 250 WORDS)

Trends in eating patterns, physical activity and socio-demographic factors in relation to postpartum body weight development

'The Stockholm Pregnancy and Weight Development Study' was conducted to identify risk factors for postpartum weight retention, such as dietary habits, physical activity and socio-demographic factors. The body weight development of 1423 pregnant women was studied prospectively from the beginning of the pregnancy until 1 year postpartum. Data were collected from routine pregnancy records and from questionnaires 6 and 12 months postpartum. Mean weight retention 1 year postpartum was 0.5 kg compared with the prepregnancy body weight. A 'trend method' was constructed to identify a number of pre-defined major patterns of behaviour. The weight retention 1 year postpartum was greater in women who (a) increased their energy intake during and after pregnancy, (b) increased their snack eating after pregnancy to three or more snacks/d, and (c) decreased their lunch frequency starting during or after the pregnancy. Women who had retained > or = 5 kg 1 year postpartum were more seldom physically active in their leisure time throughout the study period compared with women with a smaller weight gain. Postpartum weight retention correlated negatively with the degree of physical activity in the second half year postpartum. These results indicate that postpartum weight retention is more affected by a change in lifestyle during, and above all after, pregnancy than by factors before pregnancy.

Effects of weight loss on pulmonary function in obese men with obstructive sleep apnoea syndrome

The effects of long-term behaviour modification of obesity on pulmonary function was studied in eight men with obstructive sleep apnoea syndrome (initial mean body mass index [BMI] 41.8 kg m-2) before and after a mean weight loss of 20 +/- 7 (SD) kg. Mean arterial PCO2 fell from 6.3 +/- 1.2 to 5.5 +/- 0.6 kPa (P < 0.05) and concomitant significant improvements were found in vital capacity, total lung capacity, functional residual capacity and forced expired volume (FEV 1.0). The study suggests that weight loss per se, rather than the method of choice to achieve weight loss, results in clinically significant improvement of pulmonary function in obese men.