Someone said to my photo, 'you've never been slim'

I posted a healthy plate of pasta I made last night on my story. My sister commented, saying, 'You haven't lost any weight, by the way.' I was so annoyed, I can't even explain. I've been working out regularly and taking care of myself, but still, to hear something like that... Do you think I should take it to heart, or should I just ignore it?