You’ve no doubt heard about all of the health benefits that can result from drinking moderate amounts of red wine. Researchers note that dark-skinned grapes contain powerful antioxidants, such as resveratrol, that are linked to reduced risk of cardiovascular disease. Red wine is a concentrated source of resveratrol, but it contains alcohol and other compounds that can lead to negative side effects.
Red wine is fermented from dark-colored grapes, so it contains alcohol, usually between 8 and 14 percent per volume. The alcohol is primarily ethanol, which is the least toxic to people although still damaging in larger quantities. One alcoholic beverage per day is usually the limit set by most health professionals, but the metabolic by-products of ethanol are treated by the liver as a toxin. Alcohol “thins” the blood and makes it less likely to form clots, which is helpful for preventing diseases such as atherosclerosis but not so good if you have an injury that doesn’t stop bleeding. Overconsumption of alcohol, via wine or any other alcoholic beverage, increases your risk of liver disease, pancreatitis, neurological problems, high blood pressure, stomach ulcers and vitamin-B deficiencies.
Overdoing it with any alcoholic beverage can lead to “hangover” symptoms, although drinking red wine can quickly trigger a specific type of headache. Red wine headaches can occur after just a few sips and within 15 minutes. The headaches are often described as migraine-like and include nausea and flushing of the face. The most likely culprits for triggering red wine headaches are tyramine and histamine. Tyramine is commonly found in the overripe grapes used to make red wine. Tyramine causes sudden dilation and contraction of blood vessels, which can trigger severe headaches. Red wine also contains histamine, which is the chemical associated with allergic responses. Too much histamine leads to inflammation and the dilation of blood vessels, which can trigger headaches.
Another common side effect from drinking red wine is heartburn or acid reflux. The most likely culprit for heartburn is tannins, which are compounds that give red wine its astringency and bitterness. Tannins are found in the skin and seeds of grapes, which is why red wine tastes so different than white wine. The bitterness and acidity of red wine can upset your stomach and trigger more gastric juice release, which sometimes spills out of the stomach and into the esophagus causing burning chest pain. Try avoiding red wine on an empty stomach and don’t lie down while imbibing because that may trigger some regurgitation.
The acidity of red wine can also reduce the pH levels of fluids and tissues in your body, which makes them more susceptible to diseases. The pH scale is a measure of acidity, and your blood and various other tissues need to be alkaline to properly function. The tannins and alcohol in red wine are very acidic, and if you consume them in high quantities, they can create acidity problems in your body. Your blood needs to be alkaline, and it’s carefully maintained at a pH of about 7.3, but when lots of acidic foods and beverages are consumed, your body pulls minerals from your bones to keep your blood from dipping below 7.0 and becoming acidic. Over time, bones become depleted of minerals and the risk of developing osteoporosis increases. Many pathogens such as bacteria flourish in an acidic environment.
- Textbook of Functional Medicine; David S. Jones
- Human Biochemistry; Charles Dreiling
- Human Metabolism: Functional Diversity and Integration; J. Ramsey Bronk
Sirah Dubois is currently a PhD student in food science after having completed her master's degree in nutrition at the University of Alberta. She has worked in private practice as a dietitian in Edmonton, Canada and her nutrition-related articles have appeared in The Edmonton Journal newspaper.