Poria mushrooms (Poria cocos, also known as Fu Ling in traditional Chinese medicine) have been used for centuries in East Asian medical systems, particularly in China, as a supportive remedy during convalescence—the period of recovery after illness. In traditional practice, Poria is valued for its mild diuretic properties, ability to "strengthen the spleen," and its reputed capacity to tonify the body and support digestion and fluid metabolism. Classic texts often recommend Poria as part of multi-herb formulas to help restore vitality, appetite, and fluid balance in those recovering from prolonged illness or weakness.

Scientifically, there is limited direct evidence supporting the use of Poria specifically for convalescence in humans. Some preclinical studies have identified polysaccharides and triterpenoids in Poria that may have immunomodulatory, anti-inflammatory, and antioxidant effects, which could theoretically be beneficial during recovery. However, clinical trials evaluating these effects in convalescing patients are lacking. Thus, while the traditional use is well-established and supported by historical records, scientific validation for this specific indication remains minimal.

In summary, Poria mushrooms are traditionally used during convalescence in East Asian medicine, with modest mechanistic support from laboratory research, but there is insufficient direct clinical evidence to firmly substantiate these uses by modern scientific standards.