For years, Domino’s Pizza made a simple promise: order your pizza from them and they’ll get it to you in under 30 minutes — or it’s free. In the 1990s, they dropped the guarantee because drivers were running red lights, speeding, and otherwise driving recklessly in order to make their deliveries on time, in some cases leading to car accidents. Given the questionable nutritional value of their pizza (to say the least), this was just another way in which getting pizza delivered was, in all certainty, bad for your health.

In late 2007 or 2008, then-79 year old Jean Wilson put pizza to the test. Beginning around then, the Memphis, Tennessee resident made pepperoni pizza from Domino’s a way of life, ordering a large, thin crust pie — with two Diet Cokes — every day. She continued the habit for three years. The Domino’s branch she ordered from had gotten so used to her orders that they pre-made her pizzas in anticipation of her phone call.

Three years later, most people would be falling into ill health, in part because of the pizza-a-day diet. And perhaps, Ms. Wilson had a similar experience. On a Saturday in early 2011, she fell, unable to get up or to get to a telephone for help. Living alone and mostly invisible to her neighbors, Wilson’s fate looked bleak, as no one was likely to find her, lying there, any time soon. Except — by not being able to get to her phone, she also could not order the pizza.

This quirk saved her life. As reported by the TODAY show, Susan Guy, who worked at the Domino’s Wilson frequented, came to work the following Monday and learned that Wilson had not placed her usual orders over the weekend. When Wilson again “missed” her Monday order, Guy asked her manager if she could go check on their best customer — even willing to do so unpaid. She went to Wilson’s house and when no one came to the door, she asked Wilson’s neighbors if the elderly lady ever left the house. When they replied with “never,” Guy called 911. Paramedics arrived to find Wilson on the floor, unable to move, but alive.

Wilson was saved; she was admitted to the hospital and, per the same report, was eager to leave soon after — to start her pepperoni habit up anew.

Bonus fact : Domino’s only sells pizzas by the pie, not by the slice. In New York City, though, that’s uncommon, as almost all pizza places will sell customers a slice for a few bucks. One notable exception is John’s of Bleeker Street, an establishment which not only does not sell pizza by the the slice, but even puts the words “No Slices” right on its awning. As reported by the Village Voice (replete with picture of the aforementioned awning), there’s a reason for this: the mafia mandated it. As the story goes, the notorious gangster Al Capone owned some dairy farms in Wisconsin, and demanded that pizza parlors use his mozzarella — a lower-quality kind compared to the local stuff — or sell only pies, upon penalty of firebombing. John’s and a few others chose the high-quality cheese, pie-only route.

From the Archives: Waffling: How another chain eatery has a role in saving lives.

Related: A wireless help pendant. You wear it in case you fall and can’t get up and/or cannot get to a phone to get help. Hit a button and it calls 911 for you or one of five pre-determined numbers. (Please do not make Domino’s one of those five numbers.)