Indeed, research has shown that compounds in plants have pharmacokinetic effects.  Dandelion, long speculated to have antioxidant activity and hepatoprotective properties, is one such plant
Powerful Antioxidant, Resistant to Swelling
Dandelion contains chemicals whose biological activities are actively being explored for roles in human health. In particular, evidence suggests that dandelion contains antioxidant and redness-resistant compounds.  
One study investigated the antioxidative effects of dandelion root in rabbits fed a high-cholesterol diet. Results showed that dandelion positively affected antioxidant enzyme activities and lipid profiles. Researchers believe this suggests dandelion could protect against oxidative stress related to certain circulatory disorders. 
Effect of Dandelion Root on the Digestive System and Gallbladder
The Institute of Agricultural Medicine in Poland tested therapeutic herbs for kynurenic acid, an amino acid that has generated interest for digestive system support, specifically bile production. The highest concentration of this compound was detected in dandelion.  Because dandelion helps to stimulate bile production and bile transport toxins out of the body, dandelion root may support your body’s natural immune response. A study devised to compare the activity of artichoke, dandelion, turmeric and rosemary found their antioxidant activity to support the rationale the traditional inclusion of these ingredients in gallbladder applications. 
Relation to the Liver
Acetaminophen toxicity causes oxidative stress in the liver. Could natural antioxidant compounds counteract it? A study designed to answer that question found that dandelion extract demonstrated antioxidant activity against free radicals to counteract acetaminophen liver toxicity.  Animal studies have been successful in finding beneficial links between certain liver problems and dandelion.  
- Dr. Edward F. Group III, DC, ND, DACBN, DCBCN, DABFM
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