Is there any supplements that lower metabolism?

The answer is yes if you have too high of a metabolism. Iodine may help regulate metabolism, especially if the high metabolism is related to the thyroid. Oftentimes, what may appear to be high metabolism is really poor digestion, so digestive supplements like enzymes, betaine HCl, and probiotics may help. Finally, hypoglycemia, depression, and anxiety can all be related to a high metabolism, so supplements that help out those disorders can help lower the metabolism. Eating less sweets and carbs can also slow down the metabolism and level it out.