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Librarian, Christine Hall recently lost 80 pounds, and she didn’t have to join an expensive weight-loss program or sign up for a meal-delivery service to do it. In fact, Hall never even had to go to a grocery store to complete her task.

Her secret? Almost everything she consumed could be bought at Starbucks.

Hall gets her meals from the Starbucks right near work, where employees have cheered on the 5-foot, 4-inch Hall as she’s gone from weighing 190 to a trim 114 pounds.

She started tracking her calorie intake online, and eventually eating almost exclusively at Starbucks, for two years, because they include their products calorie information easily online.

“I have a busy schedule, so it just works for me,” says Hall, 66, told Health Today. “I know exactly what I’m getting. I can plan my day in advance because I’ve memorized the calories in everything.”

Hall is still eating at Starbucks, enough calories to maintain her weight, which gives her a body mass index in the normal range of just under 20.

“I want to keep it at 20 or below for the rest of my life, and that’s a very healthy place to be,” Hall said. It’s a stark contrast to when she struggled with obesity. “I has sleep apnea and I was tired all the time,” Hall said. “My joints hurt. It hurt to stand up. I was in trouble.” Now, she says, she has no medical problems, takes no medication and feels “like I’m 15.”

“I’m so blessed with good health,” she said. “I sleep like a baby and I have tons of energy. It’s great.”