Watching over the Flock: An inspector keeps a close eye on workers branding smoked hams, circa 1910. (National Archives, Records of the Bureau of Animal Husbandry)

That level is debatable, but the food supply today is certainly safer than it was in the 19th century when few laws regulated producers and manufacturers. Until 1906, food manufacturers would dump arsenic, boric acid, rat poison or formaldehyde into ingredients to act as preservatives or to cover-up spoiled meat.

Then in 1906, Congress passed the Pure Food and Drug Act and, partly in response to Upton Sinclair’s “The Jungle,” the Federal Meat Inspection Act. Food became safer to eat. The government’s impact on the American diet is the subject of the new exhibit “What’s Cooking, Uncle Sam?” at the National Archives.

The exhibit explores some of the lesser-known food hazards that Americans faced more than a century ago. Take, for example, exploding ketchup.

Alice Kamps, curator of "What's Cooking, Uncle Sam?" (Earl McDonald)

“Heinz proved fresh tomatoes made in a clean factory could last longer,” says Alice Kamps, the exhibit’s curator.

During World War II the government made posters showing people how to can food from their victory gardens. Novice canners sometimes tried to preserve wilted or spoiled vegetables or overheated them, often hurting themselves in the process.

The exhibit also explores government policy on diet, like the rationing of food during World War II.

Kamps thought of the exhibit when she first came to the National Archives in 2009. Though not a professed foodie, she knew food touched everyone. A week after opening, “What’s Cooking, Uncle Sam?” is one of the Archives’ most popular exhibits. It runs until Jan. 3.