Investors are rightly giving up on companies like General Mills and Kraft Heinz, which are squeezed by everything from inflation to GLP-1s. America's biggest food companies have tried everything to win shoppers back.

They've cut prices, ramped up marketing and added protein to everything from Cheerios to Goldfish. It hasn't worked. Profits are falling at flagship names such as General Mills and Kraft Heinz as consumers turn away from their legacy products.

Management mostly blames a strained consumer and insists conditions will improve. The market has reached a harsher verdict: These businesses are shrinking and don't know how to stop. Big Food stocks are now trading at their widest discount to the market in at least two decades. Dividend yields are unsustainably high.