Dietary fat increases energy intake across the range of typical consumption in the United States.
OBJECTIVE
The fat content of a diet has been shown to affect total energy intake, but controlled feeding trials have only compared very high (40% of total calories) fat diets with very low (20% of total calories) fat diets. This study was designed to measure accurately the voluntary food and energy intake over a range of typical intake for dietary fat.


METHODS
Twenty-two non-obese subjects were studied for 4 days on each of three diets, which included core foods designed to contain 26, 34, and 40% fat, respectively of total calories and ad lib buffet foods of similar fat content. All diets were matched for determinants of energy density except dietary fat. Subjects consumed two meals/day in an inpatient unit and were provided the third meal and snack foods while on each diet. All food provided and not eaten was measured by research staff.


RESULTS
Voluntary energy intake increased significantly as dietary fat content increased (P = 0.008). On the 26% dietary fat treatment, subjects consumed 23.8% dietary fat (core and ad lib foods combined) and 2,748 +/- 741 kcal/day (mean +/- s.d.); at 34% dietary fat, subjects consumed 32.7% fat and 2,983 +/- 886 kcal/day; and at 40% dietary fat subjects consumed 38.1% fat and 3,018 +/- 963 kcal/day.


CONCLUSIONS
These results show that energy intake increases as dietary fat content increases across the usual range of dietary fat consumed in the United States. Even small reductions in dietary fat could help in lowering total energy intake and reducing weight gain in the population.
Donahoo
William
W
Kaiser Permanente Colorado, Denver, Colorado, USA.
Wyatt
Holly R
HR
Kriehn
Joanna
J
Stuht
Jennifer
J
Dong
Fang
F
Hosokawa
Patrick
P
Grunwald
Gary K
GK
Johnson
Susan L
SL
Peters
John C
JC
Hill
James O
JO
D000328:Adult; D018592:Cross-Over Studies; D004041:Dietary Fats / Q000494:pharmacology*; D004435:Eating; D002149:Energy Intake; D004734:Energy Metabolism; D005260:Female; D006306:Health Surveys; D006801:Humans; D008019:Life Style; D008297:Male; D012528:Satiety Response / Q000187:drug effects / Q000502:physiology; D014481:United States; D015430:Weight Gain / Q000187:drug effects / Q000502:physiology; D015431:Weight Loss / Q000187:drug effects / Q000502:physiology
D004041:Dietary Fats