Why Does SIBO Keep Coming Back After Treatment? — What the Host Capacity Model says is actually happening

The Host Capacity Model (HCM) is a systems-biology framework that reframes recurrent SIBO, and the broader pattern of chronic gut dysfunction, as downstream of colonocyte bioenergetic failure rather than primary microbial dysbiosis. The full framework is at the Host Capacity Model page . This section summarizes the parts that bear directly on SIBO recurrence. The thesis is direct. The microbial composition of the colon, and the cecal and ileocecal region where SIBO presents, is determined by the bioenergetic capacity of the host's colonocytes. When the colonocyte can maintain its metabolic function, it sustains the conditions that allow the obligate anaerobic core community to dominate. When the colonocyte loses that capacity, those conditions collapse, and facultative anaerobes expand into the open niche. SIBO is the sentinel of that expansion. Recurrence is the equilibrium state of a host substrate that has not been restored. Three specific failures in the colonocyte produce this pattern. Each is mechanistically distinct. Each is a potential point of intervention. Most patients with recurrent SIBO have some combination of all three. Failure 1: SLC5A8 silencing Butyrate is the dominant fuel of the colonocyte. The cell draws 70 to 80 percent of its energy from butyrate oxidation. For oxidation to occur, butyrate must first enter the cell, and the principal apical transporter fo