Shen-chu, also known as "medicinal leaven" or "shenqu," is a traditional Chinese medicinal ferment composed of wheat flour, herbs, and yeast. Its primary use in traditional Chinese medicine (TCM) is to aid digestion and improve appetite. In the context of autoimmune disorders, there is little direct evidence—either modern or traditional—supporting its use specifically for these conditions. However, in some historical TCM practices, shen-chu has been included in herbal formulas intended to "strengthen the spleen" or "harmonize the stomach," which, according to TCM theory, may indirectly support immune health. These concepts are not equivalent to the biomedical understanding of autoimmune disorders, but the rationale is rooted in the traditional view that digestive and metabolic harmony can support the body's overall resilience.

Scientific studies on shen-chu have mostly focused on its probiotic properties and ability to aid digestion, with some research indicating beneficial effects on gut microbiota. Since gut health can influence immune function, some practitioners extrapolate potential benefits for immune-related conditions. Yet, there is a lack of direct clinical or mechanistic studies demonstrating its effectiveness in treating autoimmune diseases specifically. As a result, while its use is justified by tradition, the supporting evidence remains weak, and it should not be considered a scientifically validated treatment for autoimmune disorders.