For a long time, pet treats were like human candy: empty calories, meant for the purpose of rewarding good behavior—or bribery. That has changed. Now pet treats should have nutritional, or at the very least therapeutic, value as well. Stores shelves are filled with multitasking snacks: chews made with vitamin-laden superfoods that ease a variety of ailments and biscuits optimally shaped to clean an animal’s teeth.

During the pandemic, Numerator found, humans were more, not less, likely to buy more pet treats; the researchers speculated that this was because consumers were spending more time at home with their pets and wanted to spoil them. The average treat sales per dog in the U.S. rose from $68 in 2019 to $95 in 2021, and from $23 to $35 per cat, according to a study by the market research firm Packaged Facts. And though the study found that indulgent treats had the largest market share, at 36%, multipurpose treats have been gaining ground: functional treats now have 17% and dental treats have 15%.

Store owners shouldn’t neglect felines. Cat treats, which previously took a backseat to dog treats, have gained more of a following in the past decade or so: the market growth has outpaced dog treats every year since 2016.

The most popular supplements that show up in treats, according to the American Kennel Club, are glucosamine, which helps build cartilage in the joints; fish oil for healthy skin and fur; antioxidants to reduce inflammation and age-related cognitive dysfunction; and probiotics for digestive health.