The Importance of Fiber
As you probably recall, fiber is a component of complex carbohydrates. Because humans lack the enzyme required to break it down, fiber cannot be digested in the stomach and converted into simple sugars. Instead it acts as a gastrointestinal broom, a nutritional wonder food that can lower cholesterol; ensure regular bowel movements; and aid in the treatment of gastrointestinal conditions such as hemorrhoids, constipation, and diverticulitis.
There are two types of fiber: soluble and insoluble. Soluble fiber dissolves in water, which reduces the time it takes to empty the stomach, and lowers cholesterol levels. Good sources include dried peas and beans, apples, and oats.
Insoluble fiber — known as roughage — cannot dissolve in water but absorbs water. Insoluble fiber adds bulk to the stool and helps move food through the digestive tract, thereby preventing constipation, a problem for people with hypothyroidism.
Good sources of fiber include oatmeal, broccoli, legumes, Brussels sprouts, whole-wheat bread, green beans, and the skins of fruits.
Most foods rich in fiber are also loaded with other nutrients.
Essential
If you're trying to eat more fiber-rich food, do it slowly. Too much at once can cause uncomfortable gas and bloating. And make sure you drink enough water with the fiber to help it move through your system without causing a disruption.
In people who are battling weight gain caused by thyroid disease, a diet rich in fiber can help promote weight loss by displacing unhealthy foods with healthy ones. It can also help relieve the constipation that comes with hypothyroidism. In addition, fiber binds bile acids, which are rich in cholesterol, thereby lowering cholesterol levels.
If you do increase your intake of fiber, make sure to keep tabs on your thyroid function with routine tests. A diet rich in fiber may decrease the amount of thyroid medication that your body absorbs

