The Spleen-Fortifying, Water-Draining and Anti-Cancer Effects of Fuling (Poria)
Fuling (Poria) is a mild-medicinal, food-and-medicine water-draining and swelling-relieving herb.
Fuling cakes (fuling bing) are one of Beijing's local specialties. Fuling cakes, also called fuling sandwich cakes, were originally a Qing-dynasty imperial food and are a nourishing traditional Beijing pastry. They are thin cakes made from fuling powder and fine white flour, sandwiched with honey, sugar, and candied pine-nut fragments. Highly nourishing and tasty, they became a well-known Beijing specialty because Empress Dowager Cixi loved them.
Traditional Chinese medicine holds that Fuling is sweet, bland, and neutral, entering the spleen, kidney, and heart meridians. Its main actions are seeping dampness and draining water, fortifying the spleen, and calming the heart and spirit. Fuling both nourishes and drains water—nourishing without being harsh, and draining water without injuring upright qi—so it is used especially often in TCM formulas.
Fuling's main component is porian (fuling polysaccharide), accounting for 93% of its dry weight; it also contains poric acid, poriatinic acid, dehydrotrametenolic acid, protein, fat, lecithin, choline, histidine, ergosterol, adenine, glucose, and potassium salts.
Fuling has a marked diuretic effect on healthy people and experimental animals. It also enhances immune function, and has anti-tumor and liver- and kidney-protective effects. The ancients held that long-term use of Fuling "lightens the body"; for centuries Daoists regarded Fuling, like lingzhi (ganoderma), as an immortal's herb that could aid immortality.
Modern pharmacology also confirms that Fuling has a definite anti-aging effect. Its decoction inhibits Staphylococcus aureus, Escherichia coli, and Proteus, and has a marked antiviral effect. Fuling also raises white blood cells and lowers blood sugar, and it calms the spirit and aids sleep.
The veteran physician Yue Meizhong used Fuling alone to treat alopecia areata. Some TCM physicians use Fuling alone for children's autumn diarrhea, inner-ear vertigo, and schizophrenia. I myself have used Fuling alone for seborrheic dermatitis, with good results.
Fuling has very few side effects and is among the few TCM herbs suitable for long-term, health-promoting use by most people. Only people with frequent urination may find it worsens urinary frequency; but when combined with other herbs, Fuling can also treat frequent urination—for example, the various Di Huang Wan (Rehmannia Pill) formulas all contain Fuling.
The Shennong Bencao Jing records that Fuling "chiefly remedies counterflow qi in the chest and flanks, anxiety, grief, fright-evil, terror, and palpitations, accumulations and pain below the heart, cold and heat, vexation and fullness, cough and counterflow, dry mouth and tongue, and promotes urination. Long-term use settles the hun and po and nourishes the spirit, allays hunger, and extends years."
The Shibu Zhai Yishu summarizes Fuling most precisely: "Fuling alone is a key herb for phlegm. The root of phlegm is water, and Fuling can move water. The movement of phlegm is dampness, and Fuling can also move dampness."
Most water-draining and dampness-draining formulas contain Fuling. For cold-dampness from spleen-kidney yang deficiency, Fuling may be combined with warming herbs such as aconite (fuzi) and fresh ginger, as in Zhenwu Tang. For qi-deficiency edema, it may be combined with astragalus (huangqi) and stephania (fangji), as in Fangji Fuling Tang. For water-heat binding with yin deficiency and difficult urination, it may be combined with yin-nourishing herbs such as ejiao (donkey-hide gelatin), as in Zhuling Tang.
TCM holds that dampness mainly arises from spleen deficiency, so Fuling is also an excellent spleen-fortifying herb. Famous spleen-fortifying formulas such as Sijunzi Tang and Guipi Tang contain Fuling, and Shenling Baizhu San, which treats spleen-deficiency diarrhea, also contains it.
Fuling also calms the spirit and aids sleep, but usually it must be used together with spirit-calming herbs such as sour jujube seed (suanzaoren), polygala (yuanzhi), and dragon teeth (longchi).
Few tumor patients are without spleen deficiency, so Fuling is one of the herbs I always include in the formulas I prescribe for cancer patients. The usual adult dose in decoction is 30 g. However, Fuling is hard to dissolve in water, so its active ingredients are not easily extracted in a decoction; grinding it into powder to swallow, or taking it in pills, gives better results.
After taking Fuling, urination increases—this is a normal reaction.