Acai berry is an exceptionally nutritious fruit native to Central and South America. These berries are especially high in antioxidants and are touted as being very beneficial for cardiovascular health. Acai berry is used in a variety of dietary supplements, ranging from extracts to beverages to capsules. Consequently, the nutritional content of acai berry products differs tremendously. Fresh, raw acai berries are rich in flavonoids, which help thin your blood, and they contain some vitamin K, which promotes blood coagulation. As such, the effect of acai berries on blood-thinning medication is not currently understood, although you should consult with your doctor prior to embarking on a supplement regimen.
The acai berry is the fruit of the Euterpe oleracea palm tree, which commonly grows in Amazonian countries. The berry resembles cherries, although the coloring is darker, like blueberries. Acai berries contain a large seed and juicy flesh that has a bitter aftertaste. The raw berry is rich in many phytochemicals that display strong antioxidant activity, and is a good source of monounsaturated fats and some vitamins. Specifically, acai berries contain a high percentage of anthocyanins and other flavonoids, and are a good source of oleic acid and vitamins A and C. Acai berries contain some vitamin K and aspirin-like substances called salicylates, but are not considered a rich source of either.
People with cardiovascular disease are often prescribed blood thinners, which cut the risk of heart attack and stroke by reducing the formation of blood clots in your arteries and veins. There are two main types of blood thinners: anti-coagulant drugs, such as heparin or warfarin, which upset the chemical reactions known as the coagulation cascade and increase blood clotting times; and anti-platelet drugs, such as aspirin, which prevent blood platelet cells from clumping together to form clots.
Flavonoids, Salicylates and Oleic Acid
Acai berries are rich in flavonoids such as anthocyanin, which are powerful antioxidants able to destroy free radicals and prevent blood vessel and other tissue damage. Flavonoids also display mild anti-inflammatory and anti-platelet properties, according to "Nutrition and Wound Healing." Salicylates are aspirin-like substances that block vitamin K absorption, which is essential to the blood-clotting process. Acai berries contain some salicylate compounds, as do many other berries. Most of the fat in acai berries is in the form of oleic acid, which may also affect platelet aggregation and reduce blood clotting.
Acai berries contain vitamin K, but are not rich sources. Vitamin K is essential for blood clotting and may work against blood-thinning medication if taken in large doses. Fresh acai berries and concentrated extracts are likely to contain more nutrients than other supplements such as capsules and teas.
Acai berries have not been evaluated by the U.S. Food and Drug Administration for safety, and there no known interactions between acai berries and warfarin. However, there are at least three types of compounds in acai berries, such as flavonoids, salicylates and oleic acid, that promote blood thinning, while vitamin K is the only significant factor that promotes clotting. As such, it's possible that excessive supplementation with acai berry products may enhance the effects of blood-thinning medication, which could increase the risk of internal bleeding. Ask your doctor about the safety of consuming acai products if you're on blood-thinning drugs.