Liver capacity to oxidize fatty acids was assessed by (A) ketone body production and (B) oxygen uptake. Hepatocytes were isolated from 24 h starved Wistar rats. Cell viability was checked by a measure of (C) gluconeogenesis, in the presence of dihydroxyacetone and medium (octanoate) or long (oleate) chain fatty acids. (D) Rat liver mitochondria control state respiration was obtained with 5 Mm succinate/0.5 mM malate/1.25 μM rotenone as substrates. State 3 respirations were initiated with 1 mM ADP. Each determination was performed in triplicate from at least ten preparations for the three different diets: standard diet (white), coconut diet (black), butter diet (hatched). Results are means ± SEM. No significant difference between diets was observed.