Kelp contains more vitamins and minerals than other food. Because of its natural iodine content, Kelp has a normalizing effect on the thyroid gland. It regulates metabolism and helps the brain function normally. Thin people with thyroid trouble can gain weight by using Kelp, while obese people with thyroid trouble can lose weight with Kelp. Kelp is also used for poor digestion, flatulence, and constipation.