I personally have to be careful not to gain weight. I know this is not how people eat in this forum, but I have to eat just one meal a day, and some fruits in between to keep or loose weight. I have no idea if i have hypothyroidism or not. My temperature would certainly indicate that, but then I am wondering if RP is right about that temperature thing; maybe this is just his 'opinion'. My heart rate is high, like 80. All I can tell is that supplementing with Thyroid, natural or T3, changed nothing. Like now, i have the Thyroid-S from Thailand, and even if eat 10 grains, I don't feel a thing.
The temperature aspect is not really Ray's opinion. It was the fundamental diagnosis tool 50-60 years ago. If you go back and look at medical encyclopedias from the 40s and 50s you can see that clearly. It is pretty uncontroversial, if your temperature is low you're hypothyroid it's that simple. And you can definitely have a high heart rate independent of that, especially if you are on just one meal a day, I would not be surprised if you're running high on adrenaline a lot of the time.
I would think taking 10 grains with just one meal a day is not really something that should work, such a high amount would increase your calorie requirements substantially, so not surprising that you don't see benefits. I think nutrition and thyroid supplementation go hand and hand and should increase in lockstep. I personally needed about 4 grains for a while. Broda Barnes said 2,3,4 grains tops. Some people require more these days because life is so messed up, but 10 is likely overkill, especially since you're eating so little.