Fig. 1.

Excess ω-6 fatty acids in aging increased carbohydrate use. A: study design indicating young (6 mo old) and aging (18 mo old) mice supplied ω-6 fatty acid-enriched safflower oil (SO) diet for 2 mo. Activity monitored using the comprehensive laboratory animal monitoring system (CLAMS) indicated no change in food intake (B) and an increase in the respiratory exchange ratio (RER; C) in the SO-aging group in the nighttime. D and E: body composition analysis of lean body mass (D) and fat mass (E) of young and aging mice fed with standard laboratory chow (LC) or the ω-6-enriched diet. Red, young-LC group; black, young-SO group; purple, aging-LC group; green, aging-SO group. Values are means ± SE; n = 8 mice/group. *P < 0.05 vs. the young-LC group.