I'm no medical professional, that's who you should take advice from, but my thought would be don't obsess over the scale. And 110 pounds is very light. If you are a guy, I'd almost wonder if you are a little too light rather than trying to lose weight.
For most runners, as long as they train smart on a consistent basis (and train hard when required, but smart always) and eat healthy foods 3/4 of the time, their weight is not going to be something they need to manipulate.
Personal anecdotes for anyone who cares to have specifics:
The times I had to consciously shed weight in my running days were times I was coming off of injury. And yes, the excess baggage hurt my performance. I could generally race well up to about 166 pounds (at 6'3") but over that mark I started to fall off rapidly. There were plenty of times in college I was more like lower 160s even. I came in heavy my junior year (spotty on/off training over the summer due to some minor injury concerns) and ran my first XC race at 170 pounds, and couldn't break 26 minutes for 8k. I was down around 25:20 on the same course late in the season, and dropping the extra pounds was a part of that.
In my later 20s I also had success dropping weight after some spotty training. I was stuck up around 4:18 - 4:19 for the mile (I ran 10 seconds better than in my prime). I had recently broke my wrist so my training hadn't been ideal. But tightening up the screws on my diet and I opened up the next season in the 4:13 range. I wound up getting injured again shortly after, but the weight loss clearly worked.
TLDR in my own experience losing weight mattered most when I was just getting rolling - and I never worried about it when I had momentum in my training.