Parisians like Ms. Touvier have come to embrace a middle path. As is the case in America, companies in France have been marketing convenience foods to women for decades as liberation from kitchen drudgery. Also as in America, France has been grappling with rising rates of chronic diseases, such as obesity. But in France, where I’ve been living for nearly two years, federal and local governments acted decisively.

Among other things, Paris went to great lengths to preserve its fresh food market tradition — fruit and vegetable stands, fishmongers, butchers, fromageries — and improve the nutrition of school lunches. A prepared food sector also has proliferated alongside dual-income families, with ready-made food shops and brands like Picard offering consumers healthier alternatives to ultraprocessed junk. (The company, which has more than 1,100 stores across France, made an appearance on “Emily in Paris.”) I expected the open-air markets, but defrosted bouillabaisse and canned ratatouille weren’t what I imagined to be staples of Parisian culinary life. Yet they’ve become mainstays.

There’s no shortage of calorie-dense culinary delights, patisseries and junk food here, including at Picard. But healthy convenience is also prominent. Ms. Touvier, a critic of ultraprocessed foods, says her lab employees are 70 percent women, many of them mothers, and that she views healthier prepared foods as “part of the solution” for busy families.

French people cook more than Americans, but the country has made it easier for them to do so quickly and nutritiously. This was a conscious effort, says Serge Hercberg, an epidemiologist and former president of France’s nutrition and health program. “Until 2000, people were absolutely not aware in France about the consequences of food consumption on health,” he said. The “French paradox,” the now contested idea that France has a lower rate of coronary heart disease death despite a saturated-fat-rich diet, was widespread. Mr. Hercberg was accused of going against his culture for suggesting charcuterie and cheese were anything but delicious.

He and his colleagues soldiered through years of food industry pushback with a campaign to clean up the French food environment and slow the rise of diet-related ailments like obesity and diabetes. They lobbied successfully for soda taxes and started ad campaigns about the health benefits of fruits and vegetables (emphasizing frozen and canned food as good options). Along with Ms. Touvier, they developed Nutri-Score, a voluntary system of front-of-package nutrition labels now used in a handful of other European countries. Packaged products feature a colored scale — green A to a dark orange E, depending on how much salt, sugar, saturated fat and calories they contain, as well as how many healthy elements, such as fruits, vegetables, proteins and fiber, they include.

Dining and Cooking