Undereating and underrecording of habitual food intake in obese men: selective underreporting of fat intake.
BACKGROUND
Underreporting of food intake is common in obese subjects.


OBJECTIVE
One aim of this study was to assess to what extent underreporting by obese men is explained by underrecording (failure to record in a food diary everything that is consumed) or undereating. Another aim of the study was to find out whether there was an indication for selective underreporting.


METHODS
Subjects were 30 obese men with a mean (+/-SD) body mass index (in kg/m(2)) of 34 +/- 4. Total food intake was measured over 1 wk. Energy expenditure (EE) was measured with the doubly labeled water method, and water loss was estimated with deuterium-labeled water. Energy balance was checked for by measuring body weight at the start and end of the food-recording week and 1 wk after the recording week.


RESULTS
Mean energy intake and EE were 10.4 +/- 2.5 and 16.7 +/- 2. 4 MJ/d, respectively; underreporting was 37 +/- 16%. The mean body mass loss of 1.0 +/- 1.3 kg over the recording week was significantly different (P < 0.05) from the change in body mass over the nonrecording week, and indicated 26% undereating. Water intake (reported + metabolic water) and water loss were significantly different from each other and indicated 12% underrecording. The reported percentage of energy from fat was a function of the level of underreporting: percentage of energy from fat = 46 - 0.2 x percentage of underreporting (r(2) = 0.28, P = 0.003).


CONCLUSIONS
Total underreporting by the obese men was explained by underrecording and undereating. The obese men selectively underreported fat intake.
Goris
A H
AH
Department of Human Biology, Maastricht University, Netherlands. a.goris@hb.unimaas.nl
Westerterp-Plantenga
M S
MS
Westerterp
K R
KR
D000328:Adult; D015992:Body Mass Index; D015930:Diet Records; D004041:Dietary Fats / Q000008:administration & dosage*; D004435:Eating; D002149:Energy Intake; D004734:Energy Metabolism; D006801:Humans; D008297:Male; D009765:Obesity / Q000378:metabolism; D012044:Regression Analysis
D004041:Dietary Fats