The Thymus gland is one of the seven major endocrine glands. Located in front of the heart and beneath the breast bone, the thymus gland regulates the immune system. It is largely composed of lymphatic tissue. A weakened thymus can result in reduced immune activity. Foods which are beneficial and increase thymus function include, but are not limited to; Cabbage, cauliflower, Bok choy, kale, collard greens, watercress and arugula.