Elizabeth Sullivan, 104 Years Old, Credits Dr Pepper For Her Longevity

03/20/2015 12:42 am ET | Updated Mar 20, 2015

For one Texas woman, the best doctor in the world just might be Dr Pepper.

Elizabeth Sullivan, who turned 104 on Wednesday, says drinking three cans of the soda a day is one of the secrets to her remarkable longevity.

"Every doctor that sees me says they’ll kill you, but they die and I don’t," Sullivan told CBSDFW. "So there must be a mistake somewhere.”

One of Dr Pepper's early slogans was "Drink a bite to eat at 10, 2 and 4," to help prevent the low energy that some felt hit at 10:30 a.m., 2:30 p.m. and 4:30 p.m.

But to Sullivan, the slogan may as well have been the doctor's orders. She even drinks Dr Pepper in the morning.

“People try to give me coffee for breakfast," she told the station. "Well, I’d rather have a Dr Pepper.”

For her 104th birthday, Sullivan was given a cake shaped like a can of of Dr Pepper and plenty of soda, along with a gift basket from Dr Pepper Snapple Group CEO Larry Young.

The retired math teacher gets around with the help of a cane, but still lives in her Fort Worth home. Last year, after her 103rd birthday, Sullivan told the Fort Worth Star-Telegram that she thought people would want to die by the time they reached their 80s or 90s. Instead, she found herself having more fun than ever once she hit 90.

I could play bridge when I wanted to, drive around when I wanted to, take trips to England or whatever I wanted to,” she told the newspaper.

Sullivan said at the time that her medications were limited to a single pill a day. She didn't say what she used to help swallow it, but it would be fitting if it were one of her three daily Dr Peppers.

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