Hi all I have been gaining weight was put on levothyroxin 75 mcg after being diagnosed with hypo thyroid. I have been eating low carb 1500
cal intake for a month now Lost 7 pounds the first week on levothyroxin but gained it back the second week. I haven't changed anything with diet Is this normal?
'I have been eating low carb 15 cal intake'
What does that mean? 15 calories a day? Low carb isn't really the right diet for hypo. You need carbs for conversion. And, if you don't convert well, you put weight on, not take it off.
Do you have a copy of your last thyroid test? If so, post the results ranges here, and lest have a look. You're more than likely under-medicated. 75 mcg isn't a very high dose. How long have you been on it?
I will get my last results but just got diagnosed 16 days ago so that's what they started me on. I was hyper thyroid for 13 years then got radiated now hypo 
OK, well, that does rather change things. But you still don't want to eat too low-carb, because you're still going to have to convert that levo (T4) to T3.
However, you can't expect much in the way of change - like weight-loss - after 16 days. It's going to take at least 6 weeks for that dose of levo to be fully metabolised. You have to be patient. All things hormonal take a long time. 
Yes I just meant is it normal to loose 7 lbs and gain it all back the next I'm new to hypo always been hyper
Weight Gain.
Weight gain
Weight gain
Help! Weight Gain.
Weight gain
