"It got to the point where I was already feeling miserable because the intestinal issues and plus the self-added guilt of not getting myself to the gym or eating as healthily as possible, it was a recipe for disaster," he continued.
Kevin soon signed up for a 12-week plan with Ultimate Performance Fitness where his trainer guided him through the three month program.
He dropped from 140 to 133 pounds, lost 8.2% body fat and gained five pounds of muscle.
The Glee alum also added that the change came when he felt "terrible about his body".
He said: "I felt badly about my body. Not necessarily from a superficial standpoint, I did want to look better, but I mostly felt terrible.
"Now, I feel good, I feel like I know how to properly work out in a gym, I know how to eat well and most importantly I feel like I came away with the knowledge that'll I'll be able to use forever."
Kevin is currently dating actor, singer and songwriter Austin McKenzie, 25.
After years of speculation, the Virtually Famous host confirmed he was gay in April when he came out by the power of an Ariana Grande song.
"#NoTearsLeftToCry is gayer than me and I ACCEPT. Ty @ArianaGrande," he tweeted.
Kevin and Austin stared together in ABC's eight-part miniseries When We Rise - chronicling the gay rights movement over the past 45 years.
He played AIDS activist Bobbi Campbell.
Kevin regulary shares photos of himself with Austin, sending him a sweet birthday message late last month.
"Happy 1/2 way to 50 to the cutest boy in the world," he captioned.
KEVIN'S MEAL PLAN
• Breakfast: Two egg whites, two scrambled eggs and avocado
• Lunch: Broccoli, cauliflower and chicken thighs
• Dinner: Lean beef mince, tortillas and avocado
• Snacks: Two scoops of plant-based protein powder, hemp milk and a banana
