Now I know we're not rats,although you'd never know it the way  mainstream 
research uses the rat model. Thought this was interesting 

Physiol Behav 2002 May 1;76(1):65   Related Articles,  Links 
  
Wistar rats allowed to self-select macronutrients from weaning to maturity 
choose a high-protein, high-lipid diet.

Jean C, Fromentin G, Tome D, Larue-Achagiotis C.

Institut National de la Recherche Agronomique, Unite de Physiologie de la 
Nutrition et du Comportement Alimentaire, Institut National Agronomique de 
Paris-Grignon, 16 rue Claude Bernard F-75005 75231, Paris, France

The aim of this work was to study the evolution of rat food choice in 
relation to their age and metabolic parameters. Eighty Wistar rats were 
studied from birth to 13 weeks of age. At weaning, six litters were fed on a 
macronutrient self-selecting diet and four on a standard diet. In 
self-selecting males, protein intake was maximal at Week 7 of age and then 
plateaued (Week 13), whereas in females, protein consumption peaked at Week 7 
and then steadily decreased. Females showed a strong and early preference for 
fat, which increased continuously with age. Males and females ingested their 
total energy intake during the dark period (respectively, 79% and 70%). 
Simple meals (composed of one item) were mainly ingested during the light 
phase, while mixed meals (at least two items) were ingested during the night. 
In males, most mixed meals began with carbohydrate bouts and finished with 
proteins, while in females no particular choice was observed at the beginning 
of meals, but most of them ended with protein bouts. Body weights of either 
male and female self-selecting or control fed rats were not significantly 
different at the end of the experiment. Differences between dietary groups in 
body fat mass were not observed with the exception of higher subcutaneous fat 
found in self-selecting rats. Moreover, insulinemia was lower in both male 
and female self-selecting rats. The high-protein, high-fat diet chosen by the 
self-selecting rats could be linked to a prevention of the age-related 
insulin resistance.



http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_u

ids=12175590&dopt=Abstract

Namaste, Liz
<A HREF="http://www.csun.edu/~ecm59556/Healthycarb/index.html">
http://www.csun.edu/~ecm59556/Healthycarb/index.html</A>