Because pets are not just an emotional support but an economic burden, the change in global pet ownership is correlated with changes in GDP. The world has been getting wealthier and so pet ownership has been expanding. More pets also means more pet food demand. Pet food composition varies but is generally like that of other animals, lots of grain and plant protein.  Like animal feed, pet food manufacturers have an advantage over human food producers in that nutrition studies are more precise. Human nutrition information has historically relied upon voluntary reporting, which is notoriously imprecise. Methods are being developed to improve human nutrition understanding but for now, livestock and pets have a leg up on that knowledge bas...