What is Colloidal Iodine?
Colloidal is a unique and special formulation of iodine. Created in the 1920s, colloidal iodine offers a more bioavailable form of iodine than typical compounds of sodium iodide or potassium iodide. If you’re interested in the history of it, the creation and application for colloidal iodine was outlined in a work by WL Chandler and E J Miller in 1926.  Colloidal iodine is also known as as atomic iodine, nascent iodine, and nanocolloidal iodine. Each of these names reflects the uniqueness of this iodine form.
Typically, iodine occurs elementally as I2 or in an iodide compound, such as potassium iodide. Elemental iodine is highly toxic and caustic. Potassium iodide, as well as other iodide forms, are the way the body normally gets dietary iodine. The effort of separating iodine from potassium requires the body expend energy, making iodine absorption and use a labor intensive process. Colloidal iodine eliminates this.
Why Colloidal Iodine Works Better
Colloidal iodine eliminates the need to isolate iodine from its compound state. A solution of colloidal iodine contains isolated iodine atoms. In this state they are inactive and neither toxic nor damaging. The body can quickly absorb and use this form of iodine.
Why You Need Iodine
Life as we know it wouldn’t exist without iodine. In humans, iodine regulates metabolism and is integral to the formation of two of the most important thyroid hormones, T3 and T4. These two hormones directly affect cellular metabolism and also impact the creation of other hormones. Without adequate iodine levels the thyroid cannot maintain balanced hormone levels.
Symptoms of Iodine Deficiency
Inadequate iodine intake can lead to fatigue, the frequent feeling of being cold, difficulty with concentration, a reduced metabolism and immune function. If the iodine deficient state continues, hormonal balance, mood disorders and hypothyroidism can result. Iodine deficiency during fetal development can lead to hypothyroidism, impaired fetal and childhood neural development, and in more severe cases mental retardation and neonatal and infant mortality.   Some speculation has even surfaced questioning if there’s a link between iodine deficiency and autism in children.
While iodine deficiency has been estimated to effect up to 30% of the world’s population, too much iodine can lead to hyperthyroidism and thyrotoxicosis. 
The Best Type of Colloidal Iodine
There’s no reason to make this complicated. When looking for a colloidal iodine, look for
A true glycerin solution. Some colloidal uses alcohol which causes a burning sensation;
Completely non-toxic; and,
A pure colloidal iodine without any iodides.
If you do your homework, you’ll realize this criteria narrows the playing field. To make things easy, I recommend Detoxadine.
Dr. Edward F. Group III, DC, ND, DACBN, DABFM
W. L. Chandler , E. J. Miller. Colloidal Iodine. J. Phys. Chem., 1927, 31 (7), pp 1091–1096 DOI: 10.1021/j150277a007 Publication Date: January 1926.
Hynes KL, Otahal P, Hay I, Burgess JR. Mild iodine deficiency during pregnancy is associated with reduced educational outcomes in the offspring: 9-year follow-up of the gestational iodine cohort. J Clin Endocrinol Metab. 2013 May;98(5):1954-62. doi: 10.1210/jc.2012-4249. Epub 2013 Apr 30.
Santana Lopes M, Jácome de Castro J, Marcelino M, Oliveira MJ, Carrilho F, Limbert E; Grupo de Estudos da Tiróide. [Iodine and thyroid: what a clinic should know]. Acta Med Port. 2012 May-Jun;25(3):174-8. Epub 2012 Jul 23.
de Benoist B, McLean E, Andersson M, Rogers L. Iodine deficiency in 2007: global progress since 2003. Food Nutr Bull. 2008 Sep;29(3):195-202.