Iodine and Selenium must ALWAYS be taken together. One without the other can damage your thyroid. NEVER take Iodine without the selenium or vice versa.
I'm sure that nearly everyone here will agree that we are all here for OPTIMAL HEALTH for life. We all want to avoid doctors, health problems. So bottom line: Iodine is just a tiny part of what we need to do for optimal health every day of our life.
The remaining co-supplements have many more advantages than just Iodine supplements. I suggest taking them all for life. Prove this to yourself by doing a google search on each supplement, such as "magnesium benefits." I think you will agree that we need them all for other reasons to maintain optimal health. Decide for yourself by googling each supplement.
Additional things you and your family can do for optimal health:
1) Don't eat Genetically-Modified-Organisms foods - especially don't eat bread cereals or anything made from wheat, corn, artificial oils or anything hydrogenated, or anything made with high fructose corn syrup. http://www.wheatbellyblog.com/
Instead eat only natural fresh foods such as fish, meats, eggs, fruits, veggies nuts, and natural fats such as lard, butter & tallow.
2) drink only distilled water not city water or well water.
3) Plenty of exercise, strive for 10,000 steps per day.
4) Don't smoke, drink alcoholic beverages, pop
5) Read labels to eliminate chemicals in your food. Especially bromide, fluoride, chlorine.
I know this sounds like mission impossible, but our family and millions of others do it and it works. The road to optimal health begins with the first step, and is a lifetime journey. Don't be influenced by the TV Propaganda - good health is NOT promoted on TV. Doctors do NOT cure health problems, they only treat symptoms with expensive drugs & surgeries.