DIETARY MANIPULATION AND ENERGY COMPENSATION - DOES THE INTERMITTENT USE OF LOW-FAT ITEMS IN THE DIET REDUCE TOTAL-ENERGY INTAKE IN FREE-FEEDING LEAN MEN

OBJECTIVE: The effect of two low-fat treatments on ad libitum energy i ntake (Ei) was investigated in five lean men living within a metabolic facility. DESIGN: Diet was controlled over two consecutive periods of 12d when either, i) all foods eaten or ii) only a single (lunch) meal , was manipulated to increase the fat content from 20, 40 to 60% of en ergy, and ad libitum El measured. RESULTS: All foods: El increased fro m 8.6 (2.9 s.d.)-14.8 (3.1 s.d.) MJ/d and energy density (ED) from 4.1 (0.8 s.d.)-7.7 (1.6 s.d.) kJ/g as fat content increased from 20-60% ( P < 0.0001). There was no decrease in weight of food eaten across diet s (P>0.05) and hence no energy compensation. Lunch meal El (20%:13.1MJ /d, 40%:13.8 MJ/d, 60%:14.8 MJ/d) and ED (6.03 kJ/g, 5.89 kJ/g, 6.41 k J/g) increased but not significantly across treatments (P > 0.05), The re was partial energy compensation on the low-fat 20% diet (due in pal a to compensatory increase in fat intake), but no compensation for the high-fat 60% diet. CONCLUSIONS: Changes in total dietary fat and ED r esult in concomitant changes in EI; low fat diets reducing El. However , the dietary strategy of intermittent use of low- and high-fat items fail to significantly alter ED, and hence El, in free-feeding lean men . Whilst there is a trend towards reduction in intake, manipulation of the fat content of a single meal may not be sufficient to induce sign ificant long-term weight loss.