The Potential Toxic Side Effects of Flavonoids

Abstract

Flavonoids are a class of phytochemical molecules abundant in many plants, fruits, vegetables, and leaves.Flavonoids possess a series of significant biological activities, including anticancer, antioxidant, antiviral, and antiinflammatory properties. They become an important source of dietary supplements and natural health products. Though many studies confirmed the safety of flavonoids, the potential toxicity of flavonoids is still a remarkable field of research to be explored. The enthusiasm for flavonoids expressed by the public has sometimes overlooked their toxicity and also consumed the flavonoids exceeding the body requirements. The current review focused on the potential toxicity of flavonoids to make the public consume flavonoids with caution. This review summarizes the current toxicity which has been reported in vivo and in vitro experiments. The toxicity involves carcinogenicity and mutation, liver and kidney toxicity, and the influence on the thyroid and reproductive function and intestinal flora disorders. The mechanism of toxicity is fully complicated, and current evidence indicates that natural flavonoid glycosides act on different targets with different doses in vivo and in vitro experiments. Though most kinds of flavonoids are considered safe, flavonoids proposed as food supplements need to be assessed their tolerable upper intake level as there have been reports of toxic flavonoids.

A Comprehensive Review of the Pharmacological Importance of Dietary Flavonoids as Hepatoprotective Agents

“…Flavonoids may also interact with other medications or supplements, potentially leading to adverse efects. Furthermore, the optimal dosing and duration of favonoid supplementation for liver disease treatment are not well established, and more research is needed to determine their safety and efcacy in this context [84].…”

Flavonoids as Promising Neuroprotectants and Their Therapeutic Potential against Alzheimer’s Disease

“…The wide accessibility of flavonoids and their new expansion in utilization by people has brought up significant issues with respect to the expected harmfulness of these dietary parts [ 131 ]. Albeit most of characteristic items are all around endured; nonetheless, flavonoids and related phytochemicals have been appeared to incite neurobehavioural and endocrine-disturbing impacts [ 132 ].…”