Corrective responses in human food intake identified from an analysis of 7-d food-intake records

Abstract

Background: We tested the hypothesis that ad libitum food intake shows corrective responses over periods of 1-5 d.

Design: This was a prospective study of food intake in women.

Methods: Two methods, a weighed food intake and a measured food intake, were used to determine daily nutrient intake during 2 wk in 20 women. Energy expenditure with the use of doubly labeled water was done contemporaneously with the weighed food-intake record. The daily deviations in macronutrient and energy intake from the average 7-d values were compared with the deviations observed 1, 2, 3, 4, and 5 d later to estimate the corrective responses.

Results: Both methods of recording food intake gave similar patterns of macronutrient and total energy intakes and for deviations from average intakes. The intraindividual CVs for energy intake ranged from +/-12% to +/-47% with an average of +/-25%. Reported energy intake was 85.5-95.0% of total energy expenditure determined by doubly labeled water. Significant corrective responses were observed in food intakes with a 3- to 4-d lag that disappeared when data were randomized within each subject.

Conclusions: Human beings show corrective responses to deviations from average energy and macronutrient intakes with a lag time of 3-4 d, but not 1-2 d. This suggests that short-term studies may fail to recognize important signals of food-intake regulation that operate over several days. These corrective responses probably play a crucial role in bringing about weight stability.

FIGURE 1

Box and whisker plots of energy intake for 20 subjects determined from weighed food-intake records. Each subject provided a 7-d weighed record (n = 140). The line in the middle of the box is the mean, the box is the 25th to 75th percentile of intake, and the vertical line is the range.

FIGURE 2

Frequency distribution for individual deviations from average energy intakes (n = 280).

FIGURE 3

Relations of total daily energy intakes (A) and of deviations from average (Δ) energy intakes (B) to the percentage of fat in the diet (n = 280). The regression lines for these figures are (A) energy intake = 1327 + 20.6 × percentage of dietary fat; R² = 0.11; P < 0.0001 and (B) Δ energy intake = −265 + 8.9 × percentage of dietary fat; R² = 0.04; P = 0.0012.

FIGURE 4

Relation between percentage of deviations in total energy intake from a subject's average energy intake, on days separated by intervals of 1 d (n = 240), 2 d (n = 200), 3 d (n = 160), 4 d (n = 120), and 5 d (n = 80). The regression lines for these days are as follows: day 1, energy intake = −9.9 − 0.05 × energy intake day-1; R² = 0.003; day 2, energy intake = −17.1 − 0.078 × energy intake day-2; R² = 0.007; day 3, energy intake = −31.1 − 0.32 × energy intake day-3; R² = 0.125; day 4, energy intake = −60.068 − 0.274 × energy intake d-4; R² = 0.11; and day 5, energy int = −51.6 + 0.03 × energy intake day-5; R² = 0.002.

FIGURE 5

Average slopes (±SE) of the correlations between deviations from average energy intakes 1 d (n = 240), 2 d (n = 200), 3 d (n = 160), 4 d (n = 120), and 5 d (n = 80) apart as observed in 20 subjects, based on food-intake records obtained during 2 wk (upper panel) and the same after randomization of each subject's daily sequence (lower panel).