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Query: UMLS:C0028754 (obesity)
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An increase in the sensation of hunger and overeating after a period of chronic energy deprivation can be part of an autoregulatory phenomenon attempting to restore body weight. To gain insights into the role of fat and lean tissue depletion as determinants of such a hyperphagic response in humans, we reanalyzed the individual data on food intake and body composition available for the 12 starved and refed men in the classical Minnesota Experiment after a shift from a 12-wk period of restricted refeeding to an ad libitum refeeding period of 8 wk. For each individual, the following were determined: 1) the total hyperphagic response during the ad libitum refeeding period, calculated as the energy intake in excess of that during the prestarvation (control) period; 2) the degree of fat recovery and that of fat-free-mass (FFM) recovery before ad libitum refeeding, calculated as the deviation in fat and FFM from their respective prestarvation values (ie, the amount of fat or FFM before ad libitum refeeding as a percentage of fat or FFM during the control period); and 3) the deficit in energy intake before ad libitum refeeding, calculated as the difference between the energy intake during the period of restricted refeeding and that during the control period. The results indicate that 1) the total hyperphagic response is inversely correlated with the degree of fat recovery (r = -0.6) as well as with that of FFM recovery (r = -0.5), 2) the correlation between hyperphagia and FFM recovery persists after adjustment for fat recovery, and 3) the correlations between hyperphagia and fat recovery or FFM recovery persist after adjustment for the variance in the energy deficit during the preceding period of restricted refeeding. Taken together, these results in humans suggest that poststarvation hyperphagia is determined to a large extent by autoregulatory feedback mechanisms from both fat and lean tissues. These findings, which have implications for both the treatment of obesity and for nutritional rehabilitation after malnutrition and cachexia, have been integrated into a compartmental model of autoregulation of body composition, and can be used to explain the phenomenon of poststarvation overshoot in body fat.
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PMID:Poststarvation hyperphagia and body fat overshooting in humans: a role for feedback signals from lean and fat tissues. 906 20

In response to evidence linking obesity and high amounts of dietary fat, the food industry has developed numerous reduced-fat and nonfat food items. These items frequently derive a relatively large percentage of their energy from sugars and the effect of these sugars on weight regulation is not well known. We studied the comparative effects of high- and low-sucrose, low-fat, hypoenergetic diets on a variety of metabolic and behavioral indexes in a 6-wk weight-loss program. Both diets contained approximately 4606 kJ energy/d with 11% of energy as fat, 19% as protein, and 71% as carbohydrate. The high-sucrose diet contained 43% of the total daily energy intake as sucrose; the low-sucrose diet contained 4% of the total daily energy intake as sucrose. Twenty women aged 40.6 +/- 8.2 y (mean +/- SD) with a body mass index (in kg/m2) of 35.93 +/- 4.8 consumed the high-sucrose diet; 22 women aged 40.3 +/- 7.3 y with a body mass index of 34.93 +/- 4.4 consumed the low-sucrose diet. Mixed-design analysis of variance showed a main effect of time (P < 0.01), with both diet groups showing decreases in weight, blood pressure, resting energy expenditure, percentage body fat, free triiodothyronine (FT3), urinary norepinephrine, and plasma lipids. Small but significant interactions were found between group and time in total cholesterol (P = 0.009) and low-density lipoprotein (LDL) (P = 0.01). Both groups showed decreases in depression, hunger, and negative mood, and increases in vigilance and positive mood with time (P < 0.01). Results showed that a high sucrose content in a hypoenergetic, low-fat diet did not adversely affect weight loss, metabolism, plasma lipids, or emotional affect.
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PMID:Metabolic and behavioral effects of a high-sucrose diet during weight loss. 944 Mar 91

The aims of this study were to: describe dietary intakes of obese and nonobese middle-aged women using a validated food frequency questionnaire; to assess dietary restraint, disinhibition, and hunger by the three factor eating questionnaire (TFEQ) in obese and nonobese samples and determine which of the factors are independently associated with obesity; and to examine correlations between selected nutritional variables and the TFEQ factors. Subjects studied included 179 obese Swedish women (BMI > 32) and 147 nonobese population-based controls (BMI < 28). Age-adjusted mean energy intake was significantly higher in obese women (2730 +/- 78 vs. 2025 +/- 85 kcal, p < 0.0001). In absolute and relative terms, fat intake was higher and alcohol intake was lower in the obese subjects. Disinhibition was the strongest TFEQ factor independently differentiating the obese and nonobese states, i.e., after adjustment for restraint and hunger. Within the obese sample, strong associations were seen between energy intake and disinhibition (p = 0.0005) and hunger (p = 0.0004). The association between energy intake and restrained eating was negative and weaker (p = 0.04). No such associations were seen in nonobese women. Thus, using a dietary instrument that is valid and unbiased with respect to obesity, strong psychological correlates, possibly causal, of variability in energy intake were detected in middle-aged women with obesity. Disinhibition is associated with both obesity and high-energy intakes and is therefore an important factor to consider in the treatment of women with obesity.
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PMID:Dietary intake in relation to restrained eating, disinhibition, and hunger in obese and nonobese Swedish women. 919 90

The object of this study was to examine whether eating behavior, food preference, gastric emptying, and gut hormone patterns are altered after jejunoileal bypass (JIB) in patients with severe obesity. Eight obese [mean (+/- SD) body mass index (BMI; in kg/m2) 42.9 +/- 4] subjects were studied prospectively before and 9 mo after JIB with eight age- and sex-matched normal-weight control subjects. Total energy intake, data from the universal eating monitor (VIKTOR), eating motivation measured by visual analog scales, a food-preference checklist, a forced-choice list, solid-phase gastric emptying, and postprandial concentrations of cholecystokinin, motilin, and neurotensin were studied. BMI was reduced by 29% after JIB. Compared with normal subjects, the JIB patients showed a reduced desire to eat, decreased hunger, and reduced prospective consumption before a test meal. After surgery, obese subjects selected fewer food items and showed a reduced preference for high-carbohydrate and high-fat items before a test meal. There was a trend from an accelerated toward a decelerated eating pattern in obese subjects after JIB. After JIB, gastric emptying of obese subjects was slowed and similar to that in control subjects. Obese subjects had lower postprandial cholecystokinin concentrations that were lower than those of control subjects both before and after JIB. Postprandial concentrations of neurotensin were higher after JIB. We conclude that after JIB, the desire to eat and preference for high-carbohydrate and high-fat items is reduced, resulting in decreased energy intake. That gastric emptying is prolonged and gut hormone patterns are altered with low postprandial plasma cholecystokinin and high neurotensin plasma concentrations may at least partly account for these observations.
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PMID:Reduced food intake after jejunoileal bypass: a possible association with prolonged gastric emptying and altered gut hormone patterns. 920 88

The effect of one week of supplementation with a water-soluble fibre (guar gum) was studied in obese women who had lost weight. In study 1 (N=17; mean+/-SEM: age 38.5+/-2.3 yrs; weight 86.8+/-2.3 kg; BMI 32.2+/-0.9 kg.m-2) energy intake and hunger and satiety scores were assessed under free-living conditions. In study 2 (N=14; age 44. 5+/-1.8 yrs; weight 78.8+/-3.1 kg; BMI 29.0+/-0.9 kg.m-2) energy intake was fixed at 6 MJ.day-1 (their normal energy intake at that time) or 4 MJ.day-1 (low energy intake). In both studies, the effect of one week of fibre supplementation (40 g in study 1 and 20 g in study 2) was compared with no supplementation. In study 1, mean energy intake decreased significantly from 6.7+/-0.4 MJ to 5.4+/-0.2 MJ daily after fibre supplementation, while hunger and satiety scores did not change. At a low energy intake level of 4 MJ given in study 2, hunger scores were significantly decreased after fibre supplementation. No changes were seen in hunger and satiety scores during fibre supplementation at 6 MJ. The reduction in energy intake by soluble fibre under free living conditions and the hunger-reducing effect of fibre at the low energy intake level (4 MJ) suggests that fibre may be useful in the treatment of obesity, by facilitating compliance to low energy intake.
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PMID:Effect of one week of fibre supplementation on hunger and satiety ratings and energy intake. 926 27

At a time of increased obesity, decreased physical activity, and high food consumption, the relationship between physical activity and appetite control needs to be examined. Many people believe that the energy expended as a result of physical activity generates a drive to eat. However, a counterintuitive conclusion arises since there is no compelling evidence that increased physical activity increases energy intake. A suppression of hunger occurs following intense exercise; however, this effect is brief and has no influence on energy intake. Indeed, there does not appear to be any within-day effect of exercise on energy intake. Day-to-day effects of exercise on energy intake could occur, but only a few provocative data exist showing a delayed effect of exercise on energy intake 2 d later. Therefore, there appears to be only a weak short-term coupling between energy expenditure and energy intake. What about the effects of increased physical activity on food selection? The natural hypothesis would be that the energy reserves used during exercise would estimate a drive for a particular nutrient. There is no clear consistent evidence to indicate that in the short-term, exercise induces changes in food or nutrient preferences. In the long-term there is some evidence that physical activity is associated with an increase in carbohydrate intake, but it is uncertain whether these changes are biologically driven for a result of changes of a psychological nature. Contrary to a popularly held view, food selection and nutrient intake constitute patterns of behavior held in place by environmental contingencies and short-acting post-ingestive physiological responses; these patterns of behavior are relatively immune to modulation by the metabolic effects of exercise.
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PMID:Effects of exercise on appetite control: implications for energy balance. 926 66

To study the effect of exercise on appetite in men, hunger, thirst, taste perception, energy intake, and macronutrient choice were assessed in relation to exercise and to sauna; the latter was done to correct for dehydration and rise in body temperature. Since exercise is used to prevent and cure obesity, subjects included obese as well as nonobese men. Thirty subjects (25 +/- 7 years, BMI 22.8 +/- 1.6 and 28.5 +/- 1.9) were given twice, in random order before and after 2 h of cycling at 60% of Wmax, 2 h of sauna, or 2 h of rest, an ample choice from solid and liquid almost single-macronutrient food items and a taste perception test with solutions of sucrose, citric acid, NaCl, quinine, a mixture of these, and a carbohydrate electrolyte solution. After cycling as well as after sauna, in comparison to after rest, subjects lost 3 +/- 0.5% of body mass, while thirst, fluid intake, perception of sweet at relatively low concentrations, and percentage of energy coming from carbohydrate increased significantly. Only after cycling compared to after rest did perception of bitterness at a low concentration increase and hunger and energy intake decrease. We conclude that exercise induced a short-term reduction in hunger and energy intake, whereas exercise and sauna induced a short-term increase in taste perception of sweet at the lower concentration, while macronutrient preference of carbohydrate increased.
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PMID:Acute effects of exercise or sauna on appetite in obese and nonobese men. 938 24

Dysfunction of various hypothalamic systems may be the basis of a number of symptoms in Prader-Willi syndrome. The often abnormal position of the baby in the uterus at the onset of labour, the high percentage of infants with asphyxia and the high proportion of children born prematurely or post-maturely may all be related to abnormal fetal hypothalamic systems, as the fetal hypothalamus plays a crucial role in labour. Abnormal luteinizing hormone-releasing hormone neurones are thought to be responsible for the decreased levels of sex hormones, resulting in non-descended testes, undersized sex organs and insufficient growth during puberty. A lack of growth hormone-releasing hormone may also contribute to the short stature of patients with Prader-Willi syndrome. In addition, the aberrant control of body temperature and daytime hypersomnolence may result from hypothalamic disturbances. The number of oxytocin neurones--the putative satiety neurones--in the hypothalamic paraventricular nucleus is markedly decreased in Prader-Willi syndrome. This is presumed to be the basis of the insatiable hunger and obesity of patients with the syndrome.
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PMID:Prader-Willi syndrome and the hypothalamus. 940 39

Migraine headache is a common syndrome, afflicting millions, that has so far defied a definitive cure. Experimental research studies of the syndrome tend to describe the triggering factors separately. We propose a common denominator--namely, high levels of blood lipids and free fatty acids--as underlying factor in the development of migraine headaches. Biological states that may cause increases in free fatty acids and blood lipids include: high dietary fat intake, obesity, insulin resistance, vigorous exercise, hunger, consumption of alcohol, coffee, and other caffeinated beverages, oral contraceptives, smoking, and stress. Elevated blood lipids and free fatty acids are associated with increased platelet aggregability, decreased serotonin, and heightened prostaglandin levels. These changes lead to the vasodilatation that precedes migraine headache. We suggest that migraine headache should not be seen as an isolated symptom, but as a first signal of potential biochemical imbalances in the body, which can lead to development of chronic disease.
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PMID:In search of the ideal treatment for migraine headache. 948 75

Sibutramine (SIB), an inhibitor of serotonin and noradrenaline reuptake, has been shown in clinical trials to be associated with a dose-related decrease in bodyweight. This double-blind, placebo-controlled, Latin square crossover study examined whether the effect on bodyweight could be due in part to a reduction in daily food intake. Twelve non-dieting, women with obesity (body mass index of 30.5 to 41.9) received three treatments (0 [matching placebo], 10, or 30 mg SIB/day) for 14 days, with 14-day washout periods in between. On days 7 and 14, participants came to the laboratory to eat breakfast, lunch, and dinner so that daily energy and macronutrient intakes and ratings of hunger and satiety could be measured. Significant reductions occurred in food intake (both grams and energy) over the 14-day study period. On day 7, SIB 30 reduced intake significantly by 1762 kJ (23% reduction from placebo), and on day 14, both SIB 10 and SIB 30 significantly reduced intake compared with placebo (SIB 10, 19% reduction [1490 kJ]; SIB 30, 26% reduction [2079 kJ]). On day 7, the percentage of energy consumed from carbohydrate increased significantly with the 30-mg dose (56.7%) compared with that of placebo (51.4%), with a reciprocal decrease in energy from fat (27.8% to 24%). The results show that SIB reduced energy intake in women with obesity who were not attempting to lose weight.
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PMID:Sibutramine reduces food intake in non-dieting women with obesity. 952 64


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