Is it my thyroid or something else causing my weight gain?

[Sherlock101]

About 10 yrs ago, I suddenly started to put on weight - I doubled my weight in just over a year & this was despite there being no change in my eating habits/activity levels.  I've always been a small eater, am always the last to finish, don't eat processed foods and only grill/steam or bake my food. I did keep a food diary & my doctor agreed that I was following a healthy diet, but still couldn't give me any answers as to why my weight had gone through the roof!  Although my legs have always caused me to go up a size compared to my waist measurements, my legs now look like tree trunks and are quite solid compared to my upper arms.  My skin has become very pale with complete strangers now asking me if I'm okay. I also have numerous other symptoms as well as a B12, folate & zinc deficiency.  I've had many blood tests for my thyroid over the years which all show that I am in the 'normal' range.  What is normal?  What's normal for my neighbour may not be normal for me!  The results from my recent blood tests were:

Total T4 - 117 - reference range 58-154 nmol/L - optimal range 77-150
TSH - 1.46 - reference range 0.4-4.0 mIU/L - optimal range 1.0-2.0
Free T4 - 17.4 - reference range 10-22 pmol/L - optimal range 12-20
Free T3 - 6.21 - reference range 2.8-6.5 pmol/L - optimal range 3.4-6.0
Free T4 : Free T3 ratio - 2.8 - reference range 3.0-5.0 - optimal range 3.0-5.0
Thyroglobulin <20.0  - reference range 0-40 IU/mL - optimal range <40
Peroxidase <10  - reference range 0-35 IU/mL - optimal range <35

The results from my urine tests collected over a 24 hr period were:

Urine volume - 1000ml - reference range 600 - 2500
T3 - 860 pmol/24h - reference range 800 - 2500
T4 - 721 pmol/24 - reference range 550 - 3160
T3 T4 ratio - 1.19 - reference range ratio 0.50 - 2.30

Some of the results are on the low side.  Does this indicate anything?

Thanks

A desperate Sherlock101

[Mark Lupo, M.D.]

This is not a thyroid problem based on the labs (blood).  Urine thyroid testing is not recommended.  Would see a general endocrinologist to see if there may be another metabolic problem (ie, cushing's or insulin resistance).