Nature's Sunshine Thyroid activator is a rich source of organic iodine which nourishes the thyroid gland, strengthens thyroid function and helps improve a sluggish metabolism. Thyroid activator contains herbs to help soothe inflammation, enhance circulation to promote healing, encourage the growth of healthy colonic flora, and improve elimination and detoxification by absorbing toxins from the bowel. Thyroid Activator helps moisten dry tissues, relieve skin problems, eliminate water retention, improve digestion, enhance respiratory function and provide numerous trace minerals to nourish the body. Key ingredients includes,  Black walnut hulls are a good source of iodine, used as a thyroid stimulant to help underactive thyroid conditions.  Spirulina is a well-studied ingredient for metabolic support. It contains many functional bioactive compounds with antioxidant and immunomodulatory activities. Kelp has long been used to moisten and soften dry, hardened tissues in the body.  Parsley stimulates production of digestive fluids and enhances the elimination of wastes from inflamed joints via the kidneys. Sarsaparilla root is primarily a blood purifier, focusing most of its action in the colon.