Lucas Irwin, 25, has always struggled with his weight. However, in 2012, at his highest weight of 300 pounds, Irwin vowed to slim down and get in shape. “It’s something that I have struggled with all my life,” Irwin said. “So I started December the 28th of 2012 and just went for a year.” His determination ultimately led him to losing 130 pounds!

Irwin says that he only sees his parents a couple times a year, so when they came to visit for Christmas, they were completely shocked at his new thinner look. “I only go home once or twice a year, usually once in the summer, once for Christmas,” Irwin, 25, told TODAY on Wednesday’s show. “And I made up an excuse not to go home over the summer just so they wouldn’t see me.”

Irwin admitted that he was slightly nervous about seeing his parents for the first time since the weight loss. “When I saw my parents for the first time, I was really nervous,” he said. “I was shaking and … it was very surreal.”

Visit NBCNews.com for breaking news, world news, and news about the economy

In the video, you can see Irwin’s parents reactions to seeing their unrecognizable son. “All of the sudden, down the stairs he came,” Irwin’s father, Jeff Irwin, said. “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, Irwin’s stepmother, said. “I am so proud of him.”

So, how exactly did Irwin go from 300 pounds to 170 pounds in a year? He explains that it was mainly just from changing his diet. “I lost 95 percent of the weight just through changing my diet,” Irwin said. “I only ate 1,350 calories a day. I didn’t exercise at all until maybe seven or eight months in.”

Image via YouTube