Figure 4.

Polyphenols: classification and origin. Polyphenols are found in many fruits and vegetables and can be separated into phenolic acids, flavonoids, and non-flavonoids. Phenolic acids can be found in onion, tea, and coffee; flavonoids in grapes, pepper, broccoli, green tea, lemon, and soy; and non-flavonoids in grapes, peanut skin, and Curcuma longa. These compounds can protect the liver since they can reduce the risks for MAFLD, such as oxidative stress, inflammation, and lipid deposits. IL: interleukin; JNK: c-Jun N-terminal kinase; MAFLD: Metabolic-Associated Fatty Liver Disease; NF-KB: nuclear factor kappa B; Nrf2: nuclear factor erythroid 2-related factor 2, PKC: protein kinase C; ROS: reactive oxygen species; SREBP-1c: Sterol regulatory element-binding protein 1c.