Lucas Irwin's weight loss shocked his family over the Christmas holiday; the 25-year-old dropped 130 pounds since the last time his family saw him earlier last year.
The now 170-pound young man made a commitment to himself to lose the weight in 2013. He started his weight loss journey when he was 300 pounds, though he didn't share his intentions with his family, who he sees only twice a year. According to Irvin, he made an excuse to not visit his family over the summer.
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Irwin captured his parents' overjoyed reaction on video, which has since gone viral.
"All of the sudden, down the stairs he came," his father, Jeff Irwin, told NBC's Today show
. "And he looked just fantastic. I was more stunned than anything else. But inside, I was just beaming. I was just ... I was over the moon."
"Just picturing it in my mind again, it brings back tears to my eyes again," Susan Irwin, his stepmother, added on the Today show. "I am so proud of him."
As excited as Irwin was to reveal his new self to his parents, he remembers being nervous at first when he saw them.
"When I saw my parents for the first time, I was really nervous," he told "The Today Show." "I was shaking and … it was very surreal."
Irwin said he received support from social media, particularly through Reddit's 'LoseIt' community, where he would post his progress and receive encouragement and diet tips from other users.
The 25-year-old's weight loss secret was nothing more than sticking to a strict diet of no more than 1,350 calories a day, while keeping a journal of his daily intake.
"I lost 95 percent of the weight just through changing my diet," Irwin said. "I didn't exercise at all until maybe seven or eight months in."
"No foods were off limit, but I survived mostly on tuna salad, chicken with salsa, frozen vegetables, beans and rice, turkey/roast beef sandwiches, spinach and eggs," he wrote on Reddit
"After I lost 100 pounds I started walking to work (5 miles) for about 2 months until it got too cold outside," Irwin added.
As happy as he is with his progress, Irwin, who is 5'8," says his work isn't done and that he plans to drop another 20 pounds and maintain a 150-pound weight.
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