Do we eat less fat, or just report so?
Maneno muhimu
Kikemikali
OBJECTIVE
To examine secular trends in diet reporting error.
METHODS
Dietary information was obtained from 228 Danish men and women in 1987-88, and from 122 men and women in 1993-94.
RESULTS
Bias in dietary reporting of energy and protein intake was assessed by comparing reported intake with intake data, estimated from 24 h nitrogen output, validated by administering P-aminobenzoic acid, and estimated 24 h energy expenditure. Total energy was under-reported more than energy from protein at both surveys, suggesting that energy from other nutrients, like fat and/or carbohydrate, must have been under-reported too. There was a greater under-reporting for energy than for protein in 1993-94 (29%) than in 1987-88 (15%). Obesity was positively associated with under-reporting, both in 1987-88 and in 1993-94.
CONCLUSIONS
The higher macro-nutrient specific error in 1993-94 compared to 1987-88 may reflect a trend to increasingly omitting fat and/or carbohydrate-rich foods in dietary reporting. This may be a consequence of increased awareness of diet intake, which, in turn, may be related to intensified public health campaigns to reduce intake of fat and/or simple carbohydrate. These results may have consequences for our understanding of the apparent decline in dietary fat and associated health benefits.