Mr. lybrate-user, Thanks for the query.
Hypothyroidism if not well controlled (TSH between 3 to 4 mU/L), then there is a definite weight gain. Therefore, primary need is to achieve a strict TSH level control, by taking adequate amount of Levothyroxine
per day. Once you are able to control hypothyroidism then it is possible to loose weight and maintain a lean body. Thanks.