There are many roles and effects of Eugenol: 1. Eugenol can treat non-toxic thyroid disease and can effectively reduce the appearance of adverse symptoms due to sympathetic excitation and lower basal metabolism caused by thyroid disease. 2. If a goiter is removed, taking Eugenol after surgery can effectively prevent the recurrence of goiter. 3. Eugenol can also be used as a thyroid agent suppression test It is a drug that belongs to the treatment of thyroid disease and can not only inhibit the appearance of goiter. It can also prevent postoperative recurrence after thyroid surgery and has a therapeutic effect on the symptoms of hypothyroidism. In conclusion, there are many effects of Eugenol, but do not consume spicy, sour and other stimulating foods while taking Eugenol, otherwise it may easily induce undesirable side effects.