Another issue with low thyroid and/or testosterone is that both slow digestive process, which in turn can cause it's own set of depression like symptoms. I had SiBO (small intestine bacterial overgrowth) that caused me to not absorb vitamins B & D, and iron, and caused a lot of GI issues. This made me feel weak and tired all the time, and took a while to diagnose. SIBO is also common after radiation and chemotherapy which kill all the good bacteria. Once I cleared it up I had a lot more energy. Worth considering, especially if you have a lot of hearth burn and gas often.