Side Effects of Grape Seed Extract

Grape seed extract is rich in polyphenols which is a kind of antioxidant. Antioxidants are substances in the human body that help in suppressing the oxidation in human cells. Human cells use oxygen for some life-supporting chemical reactions. Free radicals are the by-products of this oxidation process.

Excessive production of free radicals can be a cause of several diseases like diabetes, heart ailments and cancer. Antioxidants act as scavengers for free radicals and thus prevent internal damages to the human body or repair any damages that may have occurred. Grape seed extract is made from seeds of grapes and is available in the form of tablets.

It helps in the prevention and treatment of many diseases like varicose veins and atherosclerosis, diabetes and complications related to diabetes like diabetic retinopathy, improve night vision in case of night blindness, cancer, improves blood circulation, cirrhosis, enhances bone density, candida yeast infections, etc.

The benefits of grape seed extract are extensive. However, there are a few side effects which can be categorized as minor and major. These are as follows:

Although there are a number of benefits, grape seed extract has a few side effects. Some of these are headaches, itchy dry scalp, sore throat, abdominal pain, nausea, cough and dizziness. These side effects are minor and easily curable, but it is advisable to consult a doctor before taking any supplements that contain grape seed extract.

• One of the serious side effects is bleeding. Internal and external bleeding, both are ascertained to be side effects of grape seed extract. Cuts and bruises with prolonged bleeding are observed in some cases. Internal bleeding includes symptoms like tarry stools, bright red blood in stools and vomiting blood.

• Internal bleeding also includes hemorrhagic stroke which is bursting of blood vessels inside the brain. The blood clot irritates the tissues of brain and causes swelling. The symptoms of hemorrhagic stroke are unconsciousness, coma, difficulty in swallowing, headache, loss of coordination and nausea.

• Allergic side effects are also observed, and it includes hives, itching, rash, swelling of lips and difficulty in breathing.

• Nursing women, must consult their gynecologist before taking supplements having grape seed extract as the ingredient. Grape seed extract can be harmful for pregnant women and women who are trying to conceive. In fact, the use of herbal supplements has no medical recommendation. 

This is because, grape seed extract is a herbal medicine and herbal medicines are not standardized.

• Grape seed extract reacts with other drugs, like medicines for blood thinning and anti-platelet drugs. Some pain-relieving drugs like aspirin and ibuprofen, and prescription drugs like methotrexate, cholesterol-lowering drugs and angiotensin also react with it. It interacts with the other herbs like garlic and Ginkgo biloba.

According to the University of Maryland Medical Center, grape seed extracts are not recommended for children. Instead, kids should be given whole grapes as it provides lots of health benefits. Standard dose of grape seed extracts are available from 50 mg to 300 mg. 

For general anti-oxidation process, 50 mg to 150 mg dose is recommended whereas for chronic conditions and diseases dosage above 150 mg is prescribed. This is just a suggested amount as dose may vary according to the health condition of an individual.

The Swiss Toxicological Information Center of Basel, Switzerland, has reported that grape seed extract containing benzethonium chloride in concentrations of 7-11%, can cause major health problems. However, these health problems are observed as a result of an overdose.

Thus, the dosage of any supplements should be taken, only as prescribed by the doctor. Do not forget that herbal medicines can also be harmful, if taken without proper medical advise. Be cautious and stay healthy!