Often referred to as the “master gland,” the thyroid manages important body processes, including protein creation, energy levels, and metabolism. Because metabolic output is often related to body mass, proper thyroid function is instrumental when you're trying to regulate your body weight. Thyroid deficiencies can lead to weight gain or problems such is hypothyroidism, which is a lack of thyroid hormones and commonly is preceded by iodine deficiency. 
How Iodine Affects Your Thyroid
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Thyroid, Hormones, and Metabolism
The thyroid manufactures two very important hormones, T3 and T4, which are critical to controlling the body’s metabolic rate. The key ingredient in these hormones is iodine. When the body suffers from an iodine deficiency, production of these hormones ceases, your metabolism crashes, and weight gain is inevitable. This offers insight into why persons who suffer from hypothyroidism have a difficult time losing weight. They lack the energy to exercise, and even with proper diet, their metabolism may be too slow to burn fat. Thyroid hormone levels and body weight have a relationship that quickly becomes cumulative and can easily spiral out of control. Spain's Hospital Regional Universitario Carlos Haya reported decreases in thyroid hormones when body mass increases. They surmised the change in hormone levels are influenced by increased body mass, rather than vice versa. 
Iodine is to the Thyroid as Gas is to a Car
Boosting iodine levels in the body may help stimulate the thyroid and support proper thyroid function. There are two simple methods to getting enough iodine. Eat foods that are rich in iodine; or invest in a high quality, natural iodine supplement. Across the board, research strongly supports iodine supplementation for those with thyroid problems. Italy's Department of Internal Medicine and Diabetes Center at the Catholic University arranged a study to examine the relation of thyroid function and insulin sensitivity following bariatric surgery. Bilio-pancreatic diversion (BPD) increases the prevalence hypothyroidism which can hinder iodine absorption. Iodine supplementation was recommended for patients who reported thyroid discrepancies. 
Iodine Intake Must be Adequate and Planned
There are a number of foods that will naturally boost the body’s level of iodine. Organic yogurt (Greek is best), which has exploded in popularity in recent years, is also an excellent source of probiotics. Strawberries and cranberries are also rich in iodine, as are dairy products, though you should be careful here; I commonly recommend avoiding pasteurized milk. Potatoes and organic navy beans are two vegetables you can integrate into your diet to increase iodine levels; and kelp, an edible sea vegetable, has the highest concentration of iodine on the planet.
In addition to eating more iodine rich foods, iodine supplements can boost the iodine levels in our bodies. Generally, there are four types of iodine supplements that offer maximum benefit to the thyroid gland: nascent iodine, transformative Nano-colloidal detoxified iodine, Lugol’s solution iodine, and potassium iodide. I recommend transformative Nano-colloidal detoxified iodine. This does more than just support thyroid function and optimal metabolism. Since the body uses iodine for much more than hormone production, a high quality supplement supports the body in other ways too,including neurological health. The Institute of Food, Nutrition and Health at Switzerland's Swiss Federal Institute of Technology, in a meta-analyses of iodine deficient populations, found such populations experience an average reduction in IQ of 12-13.5 points below the norm! 
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†Results may vary. Information and statements made are for education purposes and are not intended to replace the advice of your doctor. If you have a severe medical condition or health concern, see your physician.