Carbohydrate versus fat intake: differing patterns of macronutrient selection in two inbred mouse strains

Area of Science:

• Nutritional Science
• Genetics
• Obesity Research

Background:

• Understanding genetic factors influencing macronutrient selection is crucial for developing targeted obesity interventions.
• Previous studies have characterized AKR/J and SWR/J mouse strains for their sensitivity to high-fat dietary obesity.

Purpose of the Study:

• To identify mouse strains with differing macronutrient selection patterns for developing a genetic model.
• To investigate the relationship between dietary obesity sensitivity and macronutrient preference.

Main Methods:

• AKR/J and SWR/J mice were subjected to a self-selection protocol with separate carbohydrate, fat, and protein sources.
• Macronutrient intake proportions were measured during initial adaptation and after a 10-week standard chow period.
• Mice were subsequently offered composite energy diets (carbohydrate/protein or fat/protein) for further selection analysis.

Main Results:

• AKR/J mice consumed 30% more calories overall compared to SWR/J mice.
• AKR/J mice exhibited a significantly higher proportion of fat intake (69%) versus SWR/J mice (28%).
• SWR/J mice showed a significantly higher proportion of carbohydrate intake (62%) versus AKR/J mice (24%).
• In a second phase, AKR/J mice selected 85% of energy from the fat/protein diet, while SWR/J mice selected 32%.

Conclusions:

• AKR/J and SWR/J mouse strains display distinct and consistent macronutrient selection preferences.
• Findings suggest a potential correlation between sensitivity to dietary obesity and a preference for fat intake.
• These results support the use of these strains for modeling genetic influences on dietary selection.