The medic, 32, who appeared on the 2018 series of the reality TV show revealed how he was left "mortified and ashamed" by the encounter.
Captioning a hospital selfie on Instagram, the star – who has continued to practice as a doctor alongside his media work – revealed how the incident had caused him to eat "nothing" and then binge eat "for several days".
He wrote: "A few years ago, I was queuing in the cafe to get my lunch when two women came up to me.
"'Alright Dr Alex,' was quickly followed by the other squeezing my tummy and saying, 'You've put on a lot of weight since Love Island!!' They walked off laughing.
"This was in front of a queue of people as well as others sat around the canteen. I was mortified and ashamed.
"I felt so disgusted with myself that I left the queue and not only didn't eat for the rest of the shift, but nothing for the rest of the day or the next. This was followed by binge eating for several days. It really hurt. I felt ashamed to go to work in scrubs.
"Interestingly, no one would have known the effect it had on me. As for many others, that was dealt with silently."
George, who was speaking out during Eating Disorder Awareness Week, which this year is focusing on lesser-discussed male sufferers, added: "I'm not sharing this story to 'make this about me'.
"I have come a long way in my relationship with my body aside from a few hangups which we all have.
"I wanted to tell you this story because words hurt, and they can stay with you for a long time. They can be tipping points for eating disorders or trigger relapse. That was a few years ago and I can still hear their laughter. It was cruel."
George's post has received more than 64,000 'likes' with over 1,900 leaving messages of praise for his openness.
One social media follower wrote "it always astounds me the thoughtlessness of many people", while another shared "wow thank you for sharing and raising awareness, so many people need to hear your story".
If you or someone you know is struggling, support can be found via the eating disorder charity Beat
Watch: Dr Alex George on not letting dyslexia hold him back