Does my children has enough an iodine?

Am heard,that a modern person needs in iodine,but how does a find in my children?
As with cotton stick in iodine draw a net on inside shoulder side, if strips are paled for two  hours,thus an level iodine is good, and if disappeared,thus consult with endocrinologist, as a most spread thyroid damage in children is diffusion non-toxic goitre,as iodine not enough, and thyroid is enlarge, therefore in visiting for a doctor,ask his to check a neck for a thyroid enlarge sign. And signs are with a high tiredness, obesity, dryness skin, low pressure, headache, sleepiness, and abundant iodine signs are allergy reaction, as with rashes,and sneezing, heart beating often, nervousness, insomnia, sweating.Add meal with iodine as of sea cabbage, calamari, cod , shrimps, persimmon, feijoa .