Body fluid retention and body weight change in anorexia nervosa patients during refeeding.
OBJECTIVE
Body weight gain is an important goal in anorexia nervosa (AN) patients, but inflation in body fluids could artificially increase body weight during refeeding.


METHODS
42 malnourished adult AN patients were refed using a normal-sodium diet, then 176 other malnourished adult AN patients received a refeeding low-sodium diet (BMI of the 218 patients: 13.4 ± 1.9 kg/m(2)). Sodium balance, body composition by a 2-electrode impedance method (BIA, for assessment of total and extracellular water, fat-free mass, FFM), resting energy expenditure and energy intake were calculated.


RESULTS
In the patients on normal-sodium diet, body weight, and total and extracellular water gains were higher than those of the low-sodium diet patients (P<0.01). Edema occurred more often in the former group (21% vs 6%; P<0.05). In almost all patients, BMI reached a plateau around 15-16 kg/m(2), then increased again. During this plateau, an increase in intracellular water and in "active FFM" was observed with BIA, together with a similar decrease in extracellular water.


CONCLUSIONS
In AN patients, who are always afraid of gaining too much weight, in regard to their food intake, it will be useful to give a low-sodium diet until a 15-16 kg/m(2) BMI. This should be integrated into the cognitive behavioral therapy.
Rigaud
Daniel
D
Service d'Endocrinologie et Nutrition, CHU Le Bocage, B.P. 77 908, 21079 Dijon, France. daniel.rigaud@chu-dijon.fr
Boulier
Alain
A
Tallonneau
Isabelle
I
Brindisi
Marie Claude
MC
Rozen
Raymond
R
D000293:Adolescent; D000328:Adult; D000856:Anorexia Nervosa / Q000178:diet therapy*; D001823:Body Composition; D004039:Diet, Sodium-Restricted; D004487:Edema / Q000503:physiopathology*; D002149:Energy Intake; D004734:Energy Metabolism; D004750:Enteral Nutrition; D001068:Feeding and Eating Disorders / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008310:Malocclusion / Q000378:metabolism; D016055:Urinary Retention / Q000378:metabolism*; D015430:Weight Gain; D055815:Young Adult