Alexis Freed was cruelly bullied when she started high school, and ended up losing 140 lbs. — half her size — by her senior year.

Life as a high school freshman was tougher than normal for Alexis Freed. At 285 lbs., she was cruelly bullied by her classmates and couldn’t fit into the school desks.

“People would just snicker behind me,” Freed, now 22, tells PEOPLE for the 2019 Half Their Size issue. “I was so insecure that I would walk around the hallways with my head down and not make eye contact with anyone, because I figured if I look at them, they’re going to look at me and judge me.”

The Garland, Texas-native wanted to change, but “didn’t have the self-control to choose a salad over a milkshake,” she says. Instead, Freed would start her days with three bowls of sugary cereal, then eat a lunch of PB&J sandwiches, snack cakes, gummies and cheese crackers. After school she would have a full meal as a snack — more cereal, macaroni and cheese or a bag of chips — before eating two servings of dinner with her family and bowls of ice cream for dessert. Finally, she’d end the day with a bedtime snack of crackers covered in peanut butter.

“I was getting all of these health problems,” she says. “My doctor said I was pre-diabetic, and I had sleep apnea because I was so heavy that I had trouble breathing while I slept.”

Her health problems — coupled with an incident at the state fair when she couldn’t fit on a ride — motivated Freed to start losing weight.

“It took an emotional and mental toll on me,” she says. “I was like, ‘I’m only 15. I don’t want to be bigger than some of my teachers. I’m too young to have these health problems. I’m too young to be pre-diabetic simply because my eating habits and my weight. I’m so young but my body is having a hard time breathing while I’m sitting because of how much weight I have on me.’ “

In Dec. 2011, the winter of her freshman year, Freed decided to start Nutrisystem. The plan appealed to her because of the fun food options like chocolate muffins and granola, and because she could easily purchase a week’s worth of food at the nearby Walmart.

“It was just the convenience really helped me out as a kid,” she says. “I didn’t have to think about what I’m going to eat or how I’m going to prepare it.”

It took a week or two for Freed’s body to adjust to the smaller portion sizes, but soon she was losing 10 lbs. a month and felt comfortable running and exercising. She kept at it through her sophomore and junior years.

“Each year I would come back to school a little bit smaller until I was where I am now,” she says. “It was exciting.”

At the start of her senior year in Aug. 2014, Freed walked into school 140 lbs. lighter.

“I was just so much happier with myself,” she says. “I lifted my head up. I had that confidence to wave to people. I didn’t shy away from my peers anymore.”

Plus, she could finally fit into the school desks.

“I walked into my first classroom, sat in the desk, and I could even fit my backpack between me and the desk,” she says. “That’s how much of a dramatic change it was.”

In the four years since, Freed has kept the weight off while transitioning to her own eating plan full of lean proteins, leafy vegetables and fruits.

“The reason I’m able to not deprive myself and not have to follow Nutrisystem anymore is because it taught me so much,” she says. “It taught me portion control and how to have a better, healthier relationship with food.”

Now, after all of the bullying she endured at the start of her high school years, Freed says she can’t believe she’s going to be in PEOPLE.

“Don’t make fun of the girls in high school,” she says with a laugh. “You never know.”

For more, visit People.com.