Portulaca, commonly known as purslane (Portulaca oleracea), has been used in traditional systems of medicine such as Traditional Chinese Medicine (TCM). In TCM, portulaca is often categorized as a "cooling" herb and is believed to clear heat, resolve toxicity, and support gastrointestinal health. It is sometimes used in formulas intended to address conditions thought to be related to the Spleen, which in TCM theory is associated with digestion and the transformation of food into qi (energy). However, the traditional concept of the "Spleen" in TCM does not correspond directly to the anatomical spleen recognized in Western medicine and instead refers to a broader physiological function related to digestion and energy production.

Scientific research on portulaca has shown some antioxidant, anti-inflammatory, and antimicrobial properties, but these studies are not specifically focused on Spleen function as understood in either Western or TCM frameworks. There is limited to no direct scientific evidence validating portulaca’s effect on the anatomical spleen or its function. Its use for "supporting the Spleen" is thus rooted mainly in traditional practice rather than in robust clinical or experimental evidence.

In conclusion, the use of portulaca to support the Spleen is primarily justified by traditional use in systems like TCM, with a moderate level of historical evidence but limited scientific validation for this specific claim.