An animal study jointly conducted by KGK Synergize (London, Ontario), a nutraceutical contract research and product development company and the USDA suggests a compound found in the citrus fruit peel has the potential to lower cholesterol more effectively than some prescription drugs and without side-effects, reports Reuters Health. The study found that polymethoxylated flavonoids â naringenin in the peels of grapefruit and hesperetin in the peels of oranges â lowered LDL (bad) cholesterol by 32 to 40 percent in hamsters that lived on a high-cholesterol diet.