I believe this contributes significantly to the high incidence of colon cancer plaguing today's society. Beneficial bacteria also break down hormone secretions that are discharged from the liver to the small intestine. If you lack the bacteria to break down estrogen and the intestinal permeability has been altered, the patient is now reabsorbing estrogens in their original state. The body will deposit these in estrogen sensitive areas such as the breast, uterus, or ovaries, contributing, if not causing, fibroids and tumors. The same scenario is responsible for premenstrual syndrome as well.
Healthy mucosa allows nutrients to pass the barrier while blocking the entry of toxins.
With leaky gut, the barrier is dysfunctional, blocking nutrients at the damaged villi while permitting toxins to enter the blood stream. The second way antibiotics damage the intestines is by fostering the growth of Candida albicans and other pathogenic fungi and yeast. This event, more than any other, precipitates Leaky Gut Syndrome. In a healthy situation the small intestine epithelium maintains tight cell junctions, which contributes to the physical barrier involved in intestinal absorption. In addition to the physical barrier, there is an important chemical barrier within the mucus that contains immune agents which neutralize any toxin that comes in contact.