Appetite, 1990, 14, 131-132
Commentary Comments on Some Theoretical Considerations: Dietary Restraint to Binge Eating JANET TREASURE Institute of Psychiatry, London
Tuschl’s (1990) aim is to bridge the gap between the psychological concept of restrained eating and the physiological predisposition to bulimic behaviours. The paper does not tackle areas of clinical significance, but a prospective study has now confirmed the clinical impression that dieting is a forerunner of bulimia nervosa, increasing the risk eight fold (Patton, 1988). There is only brief consideration given to why some people come to have such a high investment in dieting. A growing literature suggests that constitutional factors determine metabolic rate, and hence variations in food requirements and adaptation to a change in diet. Twin studies have found that the consequence of increased nutritional intake for weight gain is under genetic control (Bouchard, 1987). Similarly, volunteers with a history of obesity fail to show the normal rise in resting metabolic rate in response to overfeeding on a high fat diet (Lean et al., 1988), have a reduced thermogenic response to caffeine (Dull00 et al., 1989) and reduced thermogenic response to noradrenaline (Connacher et al., 1988). Prospective studies have also found that variations in energy expenditure amongst southwestern American Indians correlated with change in body weight over 2 years (Ravussin et ul., 1988), and a study of babies of obese mothers found that babies with a low rate of energy expenditure became overweight 3 months later (Roberts et al., 1988). Similar studies on restrained eaters and patients with bulimia nervosa would be of great interest, and there are preliminary findings in bulimia nervosa which suggest that the nutritional requirements are decreased (Stordy et al., 1977; Newman et al., 1987; Kaye et al., 1988). In the clinical domain the overvalued ideas, which occasionally reach delusional proportions, lead to extreme weight control behaviour. Many of the characteristic symptoms arise from homeostatic responses to these habits. Prolonged fasting leading to anticipatory overeating would accord with Le Magnen’s “post-prandial correlation” theory (Le Magnen, 1985). Loss of gastric contents by self-induced vomiting probably leads to compensatory, physiologically driven increases in intake, as has been found in animals with gastric fistulae (Deutsch & Gonzalez, 1980). This may supplement the drive to eat more to facilitate vomiting. Furthermore the dissociation between the sensory properties of food and the metabolic consequences, by vomiting or calorie dilution, will extinguish all conditioned responses. What we must not do, when we puzzle with Tuschl(l990) over the heterogeneous responses of restrained eaters, is to forget the “nervosa”. If we return to Patton’s prospective study on London schoolgirls, neurotic traits, poor interpersonal Address reprint SE5 8AF, U.K. 0195~66631901020131
requests
to: Dr J. Treasure,
i-02 SO3GO/O
Institute
of Psychiatry,
De Crespigny
0
1990 Academic
Park,
London
Press Limited
132
J. TREASURF!
relationships and stressful events more powerfully and consistently predicted the development of an eating disorder than a preoccupation with dieting (Patton, 1988). Russell (1986), in a provocative essay, suggested that the neuroses change their form over time and so the neurasthenia and hysteria of Freud’s age are now replaced by eating disorders. Thus, to explain fully the development of bulimia nervosa, we will probably need to understand the pathogenesis of the neurosis.
REFERENCES Bouchard, C. (1987) Genetics of body fat, energy expenditure and adipose tissue metabolism. In E. M. Berry, S. H. Blondheim, H. E. Thiahon & E. Shafris (Eds) Proceedings of the 5th international congress on obesity. Recent advances in obesity research. Pp. 16-25. London: John Libby. Connacher, A. A., Jung, R. T., Mitchell, A. E. G., Ford, R. P., Leslie, P. & Illingworth, P. (1988) Heterogeneity of noradrenergic thermic responses in obese and lean humans. International Journal of Obesity, 12, 267-276.
Deutsch, J. A. & Gonzalez, M. F. (1980) Gastric nutrient content signals satiety. Behavioural and Neurological Biology, 30, 113-l 16. Dulloo, A. G., Geissler, C. A., Horton, T., Collins, A. & Miller, D. S. (1989) Normal caffeine consumption: influence on thermogenesis and daily energy expenditure in lean and postobese human volunteers. American Journal of Clinical Nutrition, 49, 44-50. Kaye, W. H., Gwirtsman, H. E., Obarzanek, E. & George, D. T. (1988) Relative importance of calorie intake needed to gain weight and level of physical activity in anorexia nervosa. American Journal of Clinical Nutrition, 47, 989-994.
Lean, M. E. J., James, W. P. T. & Garthwaite, P. H. (1988) Obesity without overeating? Reduced diet-induced thermogenesis in post-obese women, dependent on carbohydrate and not fat intake. In P. Bjomtorp & S. Rossner (Eds) Proceedings on theJirst European congress on Obesity. Pp. 281-286. London; Paris: John Libby. Le Magnen, J. (1985) Hunger. Cambridge: Cambridge University Press. Newman, M. N., Halmi, K. A. & Marchi, P. (1987) Relationship of clinical factors to caloric requirements in subtypes of eating disorders. Biological Psychiatry, 22, 1253-1263. Patton, G. C. (1988) The spectrum of eating disorder in adolescence. Journal of Psychosomatic Research, 32, 579-584.
Ravussin, E., Lillioja, S., Knowler, W. C., Christin, P. H. L., Freymond, D., Abbott, W. G. H., Boyce, V., Howard, B. V. & Bogardus, C. (1988) Reduced rate of energy expenditure as a risk factor for body-weight gain. The New England Journal of Medicine, 318, 467-472. Roberts, S. B., Savage, J., Coward, W. A., Chew, B. & Lucas, A. (1988) Energy expenditure and intake in infants born to lean and overweight mothers. The New England Journal of Medicine, 318, 461-466.
Russell, G. F. M. (1986) The changing nature of anorexia nervosa. In G. I. Szmukler, P. D. Slade, P. Harris, D. Benton & G. F. M. Russell (Eds.) Anorexia nervosa and bulimic disorders: current perspectives. Pp. 101-109. Oxford: Pergamon Press. Stordy, B. J., Marks, V., Kalucy, R. S. & Crisp, A. H. (1977) Weight gain, thermic effect of glucose and resting metabolic rate during recovery from anorexia nervosa. The Americah Journal of Clinical Nutrition, 30, 138-146.
Tuschl, R. J. (1990) From dietary restraint to binge eating: Some theoretical considerations. Appetite, 14, 105-109.
Commentary Comments on Some Theoretical Considerations: Dietary Restraint to Binge Eating JANET TREASURE Institute of Psychiatry, London
Tuschl’s (1990) aim is to bridge the gap between the psychological concept of restrained eating and the physiological predisposition to bulimic behaviours. The paper does not tackle areas of clinical significance, but a prospective study has now confirmed the clinical impression that dieting is a forerunner of bulimia nervosa, increasing the risk eight fold (Patton, 1988). There is only brief consideration given to why some people come to have such a high investment in dieting. A growing literature suggests that constitutional factors determine metabolic rate, and hence variations in food requirements and adaptation to a change in diet. Twin studies have found that the consequence of increased nutritional intake for weight gain is under genetic control (Bouchard, 1987). Similarly, volunteers with a history of obesity fail to show the normal rise in resting metabolic rate in response to overfeeding on a high fat diet (Lean et al., 1988), have a reduced thermogenic response to caffeine (Dull00 et al., 1989) and reduced thermogenic response to noradrenaline (Connacher et al., 1988). Prospective studies have also found that variations in energy expenditure amongst southwestern American Indians correlated with change in body weight over 2 years (Ravussin et ul., 1988), and a study of babies of obese mothers found that babies with a low rate of energy expenditure became overweight 3 months later (Roberts et al., 1988). Similar studies on restrained eaters and patients with bulimia nervosa would be of great interest, and there are preliminary findings in bulimia nervosa which suggest that the nutritional requirements are decreased (Stordy et al., 1977; Newman et al., 1987; Kaye et al., 1988). In the clinical domain the overvalued ideas, which occasionally reach delusional proportions, lead to extreme weight control behaviour. Many of the characteristic symptoms arise from homeostatic responses to these habits. Prolonged fasting leading to anticipatory overeating would accord with Le Magnen’s “post-prandial correlation” theory (Le Magnen, 1985). Loss of gastric contents by self-induced vomiting probably leads to compensatory, physiologically driven increases in intake, as has been found in animals with gastric fistulae (Deutsch & Gonzalez, 1980). This may supplement the drive to eat more to facilitate vomiting. Furthermore the dissociation between the sensory properties of food and the metabolic consequences, by vomiting or calorie dilution, will extinguish all conditioned responses. What we must not do, when we puzzle with Tuschl(l990) over the heterogeneous responses of restrained eaters, is to forget the “nervosa”. If we return to Patton’s prospective study on London schoolgirls, neurotic traits, poor interpersonal Address reprint SE5 8AF, U.K. 0195~66631901020131
requests
to: Dr J. Treasure,
i-02 SO3GO/O
Institute
of Psychiatry,
De Crespigny
0
1990 Academic
Park,
London
Press Limited
132
J. TREASURF!
relationships and stressful events more powerfully and consistently predicted the development of an eating disorder than a preoccupation with dieting (Patton, 1988). Russell (1986), in a provocative essay, suggested that the neuroses change their form over time and so the neurasthenia and hysteria of Freud’s age are now replaced by eating disorders. Thus, to explain fully the development of bulimia nervosa, we will probably need to understand the pathogenesis of the neurosis.
REFERENCES Bouchard, C. (1987) Genetics of body fat, energy expenditure and adipose tissue metabolism. In E. M. Berry, S. H. Blondheim, H. E. Thiahon & E. Shafris (Eds) Proceedings of the 5th international congress on obesity. Recent advances in obesity research. Pp. 16-25. London: John Libby. Connacher, A. A., Jung, R. T., Mitchell, A. E. G., Ford, R. P., Leslie, P. & Illingworth, P. (1988) Heterogeneity of noradrenergic thermic responses in obese and lean humans. International Journal of Obesity, 12, 267-276.
Deutsch, J. A. & Gonzalez, M. F. (1980) Gastric nutrient content signals satiety. Behavioural and Neurological Biology, 30, 113-l 16. Dulloo, A. G., Geissler, C. A., Horton, T., Collins, A. & Miller, D. S. (1989) Normal caffeine consumption: influence on thermogenesis and daily energy expenditure in lean and postobese human volunteers. American Journal of Clinical Nutrition, 49, 44-50. Kaye, W. H., Gwirtsman, H. E., Obarzanek, E. & George, D. T. (1988) Relative importance of calorie intake needed to gain weight and level of physical activity in anorexia nervosa. American Journal of Clinical Nutrition, 47, 989-994.
Lean, M. E. J., James, W. P. T. & Garthwaite, P. H. (1988) Obesity without overeating? Reduced diet-induced thermogenesis in post-obese women, dependent on carbohydrate and not fat intake. In P. Bjomtorp & S. Rossner (Eds) Proceedings on theJirst European congress on Obesity. Pp. 281-286. London; Paris: John Libby. Le Magnen, J. (1985) Hunger. Cambridge: Cambridge University Press. Newman, M. N., Halmi, K. A. & Marchi, P. (1987) Relationship of clinical factors to caloric requirements in subtypes of eating disorders. Biological Psychiatry, 22, 1253-1263. Patton, G. C. (1988) The spectrum of eating disorder in adolescence. Journal of Psychosomatic Research, 32, 579-584.
Ravussin, E., Lillioja, S., Knowler, W. C., Christin, P. H. L., Freymond, D., Abbott, W. G. H., Boyce, V., Howard, B. V. & Bogardus, C. (1988) Reduced rate of energy expenditure as a risk factor for body-weight gain. The New England Journal of Medicine, 318, 467-472. Roberts, S. B., Savage, J., Coward, W. A., Chew, B. & Lucas, A. (1988) Energy expenditure and intake in infants born to lean and overweight mothers. The New England Journal of Medicine, 318, 461-466.
Russell, G. F. M. (1986) The changing nature of anorexia nervosa. In G. I. Szmukler, P. D. Slade, P. Harris, D. Benton & G. F. M. Russell (Eds.) Anorexia nervosa and bulimic disorders: current perspectives. Pp. 101-109. Oxford: Pergamon Press. Stordy, B. J., Marks, V., Kalucy, R. S. & Crisp, A. H. (1977) Weight gain, thermic effect of glucose and resting metabolic rate during recovery from anorexia nervosa. The Americah Journal of Clinical Nutrition, 30, 138-146.
Tuschl, R. J. (1990) From dietary restraint to binge eating: Some theoretical considerations. Appetite, 14, 105-109.
