Soy fiber is sometimes used as a dietary intervention for diverticulitis, primarily as a means to increase overall dietary fiber intake. There is scientific support for the general recommendation of increased fiber intake in the management and prevention of diverticular disease, though not specifically for soy fiber over other fiber types. Clinical guidelines and meta-analyses suggest that a high-fiber diet may decrease the risk of symptomatic diverticular disease and reduce recurrence after acute episodes, but most of the evidence pertains to fiber in general (including both soluble and insoluble types) rather than soy fiber specifically.

Soy fiber is an insoluble fiber derived from soybeans. Insoluble fibers help increase stool bulk and promote regular bowel movements, which can reduce colonic pressure and the risk of diverticula formation or complications. Some studies have noted that insoluble fiber, which includes soy fiber, is associated with a lower risk of diverticular disease, although the data are not specific to soy fiber alone. The American Gastroenterological Association and other professional bodies recommend dietary fiber for patients with a history of diverticulitis, but do not specify soy fiber over other sources.

In summary, while soy fiber is not uniquely validated for diverticulitis, its use is supported as part of the broader recommendation for increased dietary fiber intake. The evidence base is moderate for fiber overall (hence a score of 3), but specific, high-quality studies on soy fiber for diverticulitis are limited.