If you have low thyroid, you may not be getting enough iodine. Iodine is the key mineral your thyroid needs to function, but your body does not produce it on its own. See, iodine was intentionally added to salt in 1924 to help with the iodine deficiency epidemic. This was a result of iodine depletion in our soil due to natural causes. Besides being in seafood, it is not easy to get enough iodine naturally. Pure cranberry juice is a natural source of iodine. I drink 4oz each day. I also make sure to add plenty of salt, both iodized and sea salt (or Himalayan salt) to my homemade meals. Adding salt is especially important to clean eating athletes to ensure you're getting enough electrolytes, which improve performance + recovery. You lose both salt and iodine when you sweat. Oh, and its even more important to get enough iodine if you are pregnant and/or breastfeeding for fetal brain development.