Submitted to: Experimental Biology
Publication Type: Abstract only
Publication Acceptance Date: 4/15/2003
Publication Date: 4/15/2003
Citation: Rumpler, W.V., Rhodes, D., Paul, D.R. 2003. The impact of covert manipulation of macronutrient intake on energy intake (ei) and macronutrient selection. Experimental Biology. Interpretive Summary: none
Technical Abstract: The impact of covert manipulation of macronutrient intake on energy intake (EI) and macronutrient selection. William Rumpler, David Paul, Donna Rhodes. Beltsville Human Nutrition Research Center, Beltsville, MD 20705 Twelve men were fed a defined beverage continuously for two 8-week periods but allowed unrestricted access to a variety of approved foods, varing in composition. Every item consumed by the subjects was recorded at each meal. Each subject received 2 of 3 treatments that consisted of the consumption with each meal (3X/d) of a 698 kJ drink (2093 kJ/d) that was predominately carbohydrate (CHO), fat (FAT) or a combination of protein and carbohydrate (PRO). There were no significant changes in body weight or fatness related to treatment or duration of feeding. Average EI during week 1 - 2 was 6% lower on CHO than either FAT or PRO but this effect disappeared by week 7 - 8. EI increased by 8% from week 1 to 8 with CHO through the increased consumption of fat and protein-containing foods, but not carbohydrate. These results demonstrate short-term responses in EI to manipulation of the macronutrient intake. However, these effects disappear when feeding is continued past a few weeks. These data suggest the presence of macronutrient-specific regulatory mechanisms in the body, but do not support the notion that a high intake of any of the three macronutrients suppresses EI over a prolonged period of time.