Beta-Sitosterol decreases intestinal absorption of cholesterol by about 50% by competing for limited absorption space. Grape polyphenols, particularly flavonoids, have a wide variety of effects including antioxidant, vessel widening, and anti-clotting properties that promote circulation and enhance vein health, and garlic is thought to protect blood vessels from injury by reducing oxidative stress, inhibiting low-density lipoprotein (LDL), or bad cholesterol, oxidation, and preventing blood clots.