" The people who have trouble with the actual thyroid hormone they can be either deficient in magnesium because hypothyroidism makes all of your tissues fail to retain a normal amount of magnesium and then when you supplement it, suddenly you experience an extreme magnesium deficiency in your heart, for example, and your brain, and so taking some magnesium at the same time as the thyroid will help those people. Others, if they are deficient in adrenal or ovarian or gonadal steroids, will suffer stress symptoms when they take thyroid and so using a supplement such as pregnenolone will make them tolerate adapting to the thyroid hormone more easily. RP: When people have suffered for a long time with a low thyroid they are likely to have extremely high adrenalin and cortisol levels and that causes them to turn T4 into reverse T3 blocking the actual active T3 hormone and then if they accumulate more and more T4 that will interfere competitively with the little bit of T3 that they do...