core inflation

It seems to me that one potential problem with using "inflation excluding food and energy" as a measure of core inflation is that food and energy both have particularly low income elasticities of demand. The core inflation measured may be more pro-cyclical than overall inflation. Perhaps it's not a big enough effect to be a concern; it should also be noted that any effect that is primarily linear with the overall level of inflation, as this may be, would simply suggest a different calibration by economic agents for the use of the information, and wouldn't actually change the informational content of the data.