The tablets are formulated to be free from GMO, gluten, lactose, and wheat. Why Choose Prowise Sea Kelp?. It is the most abundant natural source of iodine. Ingredients: Bulking Agents (Dicalcium Phosphate, Microcrystalline Cellulose), Sea Kelp (Ascophyllumnodosum) 35:1 Extract, Anti-Caking Agents (Magnesium Stearate, Silicon Dioxide).