Can i lose weight by keeping my thyroid level in check ?

Perhaps?: Using thyroid medication is no way to lose weight but if you are hypothyroid and on replacement, keeping your thyroid level under proper control may allow you to lose weight you gained as you developed hypothyroidism. You may not lose fat but you may lose edema (water weight). Follow a prudent diet, exercise and follow closely with your pcp, endocrinologist or other.

Depends on your goal: Your thyroid does control metabolism to some degree, but low thyroid levels tend to account for small amounts of weight gain (usually ~5lbs; maybe a little more if severely low causing water retention- but then u'd have bigger problems) so if u had low thyroid and properly treat, yes it may help a bit. If youre very overweight, likely diet and exercise habits play bigger role in your weight.