Acerola is a shrub in the Malpighia family of plants and is also known as Barbados cherry, West Indian cherry and wild crapemyrtle. It grows in tropical areas worldwide, and its small bright-red fruits are extremely high in vitamin C, providing around 1,500 milligrams per 100 milligrams of fruit, with the green fruits possibly even twice that amount. Although acerola is a powerful antioxidant, because of its high vitamin C content it has many of the same side effects that the vitamin does.
Drug and Test Interactions
Acerola can cause a false negative result in stool occult blood tests if you ingest it 47 to 72 hours before a test, according to "The Essential Herb-Drug-Vitamin Interaction Guide" by George T. Grossberg. Acerola can also give you a false decrease in a glucose oxidase test like Clinistix if you ingest more than 500 milligrams of acerola-vitamin C prior to the test. It can also cause a false increase on a cupric sulfate test such as Clinitest.
Acerola can also interact with many prescription drugs, particularly birth control pills and other estrogen-containing medicines, so you should consult your doctor before taking acerola. Grossberg also warns that taking acerola while on fluphenazine can decrease levels of the drug in the blood and it can also reduce the anticoagulant activity of warfarin.
If you take more than two grams per day of acerola, you may experience nausea, diarrhea and abdominal cramps, although there have been some reports of such symptoms from as little as one gram per day. According to the Purdue University Horticulture Department's report on acerola, physicians in Curacao reported that children often require treatment for intestinal inflammation and obstruction caused by eating wild Barbados cherries. Due to the acidic content of acerola, esophagitis can also occur if you use acerola for a prolonged period of time.
If you ingest large enough quantities of acerola, the vitamin C content may enhance iron absorption, leading to iron poisoning, which is mostly a problem if you have a rare iron overload disorder, such as haemochromatosis. Higher doses can also cause hemolysis, an abnormal breakdown of red blood cells either in the blood vessels leading to a form of anemia, although this is primarily seen in patients who have a concurrent glucose-6-phosphate dehydrogenase deficiency.
Although the relationship between higher doses of any vitamin C product like acerola and the development of kidney stones is controversial, one study at the Department of Food Science and Human Nutrition, Washington State University, found that 1,000 milligrams of ascorbic acid twice each day increased urinary oxalate and Tiselius Risk Index for calcium oxalate kidney stones in 40 percent of participants, both those who formed stones and those who didn't.
Some people have experienced a migraine headache with doses as high as 6 grams per day, as well as other nervous system side effects such as dizziness, faintness and fatigue. If you are prone to migraines or dizziness, you should avoid taking large doses of acerola.