Grant Grimes, 22, of Atlanta, lost 120 pounds

Current weight: 420 pounds

Pounds lost: 120 pounds

Height: 6 feet

Age: 22 years

How long he's kept it off: He started June 2013 and reached his current weight this month.

Personal life: Grimes works for Sodexo as the student promotions coordinator for Georgia Tech dining services. "I study business administration with a concentration in marketing and certificate in finance at the Scheller College of Business at Georgia Tech," says Grimes who lives in Atlanta.

Turning point: "I had a few turning points during my journey," he says. "I have been inspired to lose weight since my senior year of high school when I lost a close family friend due to a heart attack at age 47." When the on-campus nutritionist was out on maternity leave, it was up to Grimes to implement the Mindful by Sodexo program (https://mindful.sodexo.com/). While teaching others the new healthy recipes, he soon found himself exchanging daily soda for water, "I truly committed to changing my lifestyle…"

Diet plan: "I eat approximately 2000 calories per day…and exercise to further increase the calorie deficit. This exercise also keeps my muscles intact and since starting, my muscle mass has actually increased - the entirety of my weight loss has been pure body fat." He starts with oatmeal and turkey sausage. Lunch is a salad. Dinner is lean protein, vegetables and whole grain.

Exercise routine: "I exercise three to four times a week for an hour and a half," he says. "My routines consist of cardio, which is either swimming or running on an elliptical, and strength training through the use of machines, presses and free weights. I also supplement these workouts with fitness classes…and walk more on days when I am not working out." He uses a FitBit fitness tracker and My Fitness Pal.

Biggest challenge: "My biggest challenge has been maintaining momentum. [I] didn't lose more than four pounds in the first two weeks of January even though I followed the same plan." He's learned to ramp up his workouts and cut extra calories.

How life has changed: "Buying smaller clothes, while still a hassle, feels a lot better than struggling to find a shirt that fits," he says. "My lower back pain and knee pain have both significantly lessened…I have more energy than ever and am willing to try things that I would never have considered before, like a 5K… I could not have done this without the support of my friends and family, and cannot thank them enough. However, based on my own experience, you are the key-holder for your success, and unless you truly want to change, no amount of support will lead to sustainable results."