Re: can i avoid weight gain after my thyroid operation
A partial might not effect your levels too much over time, but it can initially, or it can permanently, you just don't know--the truth is your levels can be off now before surgery, and then later too.
When I had my thyroid total surgery for cancer, I didn't use thyrogen afterward (nowdays you can) for my RAI, so I was on no meds at all after surgery for about 6 weeks, and was concerned about weight gain. I had absolutely no thyroid hormone in my body in the last few weeks.
Although I had water retention, I just forced myself onto my treadmill, and I ate a good diet for that time (except for ice cream after surgery) mostly salads and proteins, very little junk.
I didn't gain weight, maybe a pound or so of water---but I had to work hard, it wasn't fun or easy. My surgeon had warned me I would gain, but I worked not to.
You might want to focus first after a few weeks of surgery on getting to a good hormone level, so weight maintenance will be much easier. But it's certainly not written in stone that you will gain weight after a partial or a total.