In fact, Colas said such patterns show "a pattern reminiscent of past recessions," though traditional indicators are not pointing in that direction.
"Sometimes the official data is fine, but we think it never hurts to triangulate against other signposts we see on the road," Colas said in a note Friday. "(Conventional) wisdom is sometimes wrong, after all."
Indeed, the direction of food prices has been hotly contested among economists in recent days.
Judging by the consumer price index, food is falling. The Department of Labor indicator showed the "food at home" index tumbled 1.9 percent over the past 12 months, with 5 of 6 grocery store indexes falling during that time. Meat, poultry and eggs plunged 6.5 percent.
However, going out to eat has gotten more expensive. That index increased 2.8 percent for the year-over-year period. (For comparison, the U.N.'s Food and Agriculture Organization food price index, which measures prices internationally, rose 1.9 percent on a monthly basis in August and 7 percent annualized.)
The BCI jibes with a number of other Colas indicators that show slow economic growth. They include gas prices and food stamp enrollment (both falling), pickup truck sales that are flat, mutual fund outflows and Gallup's survey of daily spending patterns, which has been range-bound for two years.
"The upshot of all this is that the US economy isn't really accelerating; it may, if items like the pickup truck data or the Gallup spending information, be slowing a little," Colas wrote. "There may be some core inflation, but everyday items like food are showing deflationary pressures. If you tore up the Fed's usual briefing books and indicators, would you see enough reason for a rate hike in December?"