Flavanone is the basic chemical skeleton for the class of compounds known as Flavanoids. Flavonoids are naturally occurring secondary plant metabolites. They are mainly found in cereals and herbs. In the western diet, the estimated daily intake of flavonoids is in the range of 20 -50 mg per day. Flavonoids as a class generally have effects on CYP (P450) activity, and therefore may affect drug metabolisms.

Hesperetin is a cholesterol-lowering flavanoid found in a number of citrus juices. It appears to reduce cholesteryl ester mass and inhibit apoB secretion by up to 80%. Hesperetin may have antioxidant, anti-inflammatory, anti-allergic, hypolipidemic, vasoprotective and anticarcinogenic actions. In vitro research also suggests the possibility that hesperetin might have some anticancer effects and that it might have some anti-aromatase activity, as well as activity again. Hesperetin reduces or inhibits the activity of acyl-coenzyme A: cholesterol acyltransferase genes (ACAT1 and ACAT2) and it reduces microsomal triglyceride transfer protein (MTP) activity. Hesperetin also seems to upregulate the LDL receptor. This leads to the reduced assembly and secretion of apoB-containing lipoproteins and enhanced reuptake of those lipoproteins, thereby lowering cholesterol levels. Hesperetin's 7-O-glycoside, hesperidin, is a naturally occurring flavanon-glycoside, the main flavonoid in lemons and sweet oranges.