I started avoiding soy last year. For years, I noticed I could never sleep on nights when we had eaten Chinese food. At first, I thought it was the tea and stopped getting that. Then last year I started eating tofu and got a bad headache every time. So now I avoid soy completely. We still eat Chinese food but I try to order something that doesn't have much or any soy.Friend of mine is an endocrionologist, he said when the metabolism changes somewhat or seems to slow down, it is in 90% of all cases down to thyroid, and women are much more at risk and their main risk factors are hormonal changes, puberty, child birth, menopause and hormonal birth control. The body is a finely tuned chemical factory with a bunch of electricity thrown in, I'm hypothyroid anyway, so some food I have to avoid because it slows the thyroid down even more and can block the absorption and conversion of the thyroid hormones. Since I avoid soy and steam cruciferous vegetables, I noticed a total difference, plus upping my D3 and B12. A change that might not even show up in a blood test because it is so small, is often enough for your body to recognize.
My mother and my sister both had thyroid problems. The last time I checked mine was fine but the doctor wanted to run more tests. I am absolutely positive that my hormones affect my weight. I've lost a lot of weight several times in my life without any effort on my part, yet when I try to diet, it hardly ever results in weight loss, quite often just the opposite. My most recent weight loss was from an accident, hospital stay, and a virus.
I have insomnia and I have read that not getting a good night's sleep can make you gain weight. It doesn't seem fair. All that tossing and turning should burn calories!