The moment 33-year-old Rebekah Ceidro crossed the finish line at the University of Pittsburgh Medical Center Pittsburgh Half Marathon was the first time in her life she truly felt like a runner.

Less than a year earlier, Ceidro weighed more than 200 pounds and would routinely "drop something in the fryer" when she got hungry in between managing an Eat’n Park restaurant outside of Pittsburgh, Pennsylvania, and taking care of her 3-year-old son, Noak.

"I just thought I had to do something," Rebekah Ceidro said of getting healthy enough to donate her kidney. Rebekah Ceidro

That all changed when she came across a Facebook post by friend and former co-worker Chris Moore. A lifelong sufferer of chronic kidney disease, Moore, 30, had received some startling news. In six months to a year, his doctors said, he would require a kidney transplant, or worse, dialysis.

“I just kept seeing the post and it would tug at my heart. You don’t think about things like that when you are 30 years old. You think about when you are going to get married, not ‘How am I going to save my own life?’” Ceidro told TODAY.

“I didn’t see any call for action. I didn’t see any people saying, ‘What can I do to help?’ And I just thought I had to do something.”

It was then that Ceidro decided to donate her kidney to save Moore’s life, and in the process, change her own life.

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She messaged Moore on Facebook, and as chance would have it, they shared the same blood type.

Ceidro immediately took steps to begin the donor process. She visited the medical team at University of Pittsburgh Medical Center to begin testing for the live organ donation process. But she hit a snag. At 5 feet 7 inches tall and 213 pounds, she was too heavy to be a donor.

Chris Moore needed a kidney transplant to save his life. Rebekah Ceidro

As a general rule, most organ donation clinics require candidates under 40 years old to have a body mass index — or a measurement of body fat, based on height and weight — of 32 or lower to minimize the risk for complications and lessen recovery times.

That meant Rebekah would have to lose about 15 pounds.

“What’s uniquely different about the donor operation is that these are people are very altruistically and very nobly putting themselves in harm’s way for someone else,” Dr. Amit Tevar, associate professor of surgery at UPMC, told TODAY. “Our job is pretty simple: it’s to make sure the donors have a safe process and we don’t put them at any undue risk.”

Ceidro made it her goal to run a 5K every day while training. Rebekah Ceidro

Furthermore, prematurely obese individuals have a higher risk of Type 2 diabetes in later years. Diabetes can damage kidneys and, in some cases, lead to diabetic kidney disease.

“Admittedly, I was really angry that two individual surgeons would have the audacity to say such a thing, but they were right,” Ceidro told TODAY. “My actual thought was, ‘I’m too fat to save my friend’s life.’ And that sucked, but that’s at least something you can change.”

Ceidro wasted no time in changing her lifestyle. She downloaded several apps to help monitor her nutrition and fitness and enrolled in a 5K race hosted by her company, Eat’n Park.

Running a 5K only a few weeks into her fitness regimen was tough for Ceidro, but she didn’t let it defeat her.

“I use her courage to give myself courage. If she can do this, then I can do this,” Moore said. University of Pittsburgh Medical Center

“I thought, ‘This is what I’m going to do, I’m going to start running and keep running until I can do a 5K every day,” Ceidro told TODAY.

And that’s exactly what she did. By winter, Ceidro was running about three to four miles per day and had begun incorporating weight training into her regimen. By spring, she had lost about 40 pounds. On May 7, she finished the UPMC Health Plan Pittsburgh Half Marathon in three hours 14 minutes.

“The marathon was like this mountain that I needed to climb in my own life to see if I could get to the top,” Ceidro told TODAY. “It was a feeling like there wasn’t anything in the world I couldn’t accomplish because I just accomplished this.”

As for Moore, he sees Ceidro not only as a generous donor, but as an inspiration.

“I use her courage to give myself courage. If she can do this, then I can do this,” Moore told TODAY.

Doctors are prepping Moore and Ceidro for transplant surgery within three to six months. Barring any setbacks, Ceidro hopes to participate in the Pittsburgh Marathon in May 2018.

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