Is Wine Good for You?
By Mohammad Ahrar, PhD
Introduction
Wine has been associated with significant physicochemical properties beneficial to consumers’ health. It is the alcohol content and the amounts consumed that raise the red flag about the health benefits of alcoholic beverages. In this article, general information about wine and the pros and cons of wine consumption will be discussed.
General Composition of Wine
Wine’s chemical composition is complex and primarily consists of water (about 86%), ethanol (8–15%), glycerol and polysaccharides or other trace elements (1%), different types of acids (0.5%), and a large variety of polyphenols (ranging from 2000 to 6000 mg/L in red wines), which are responsible for the special organoleptic features of wine (color, flavor, smell).
Nutritional Value of Wine
Wine is not known for its nutritional properties. The major nutrients that humans need—such as proteins, fats, carbohydrates, minerals, and vitamins—are very limited in wine, so it doesn’t meet the daily nutrient requirements for people. However, wine contains bioactive chemicals such as phenolic compounds that have some health benefits. In red wine, up to 90% of the wine’s phenolic content falls under the classification of flavonoids. These phenols, mainly derived from the stems, seeds, and skins of grapes, often leach out of the fruit during the maceration period of winemaking.
Health Benefits of Wine
Links between red wine and fewer heart attacks aren’t well understood. Studies show that drinking a moderate amount of wine has some health benefits due to the presence of polyphenols in grapes, which play a role as antioxidants and anti-inflammatories in the body. (1)
Antioxidant advantages: The antioxidant property of polyphenols helps fight free radicals (unstable molecules) caused by food metabolism in the body and environmental factors such as air and water pollution. The buildup of free radicals damages your cells, called oxidative stress, which can lead to a range of health conditions, such as autoimmune disease, heart disease, aging skin, neurodegenerative diseases, and even cancer. Antioxidants can limit or prevent oxidative stress.
Reducing inflammation: Polyphenols in wine have anti-inflammatory properties, and moderate intake of wine can reduce inflammation. (2) Medical studies show that inflammation can lead to a wide range of chronic diseases such as arthritis, the cardiovascular system, the digestive systems, and almost all body organs.
More information about inflammation and the role of antioxidants is found in Peyk #184.
Lowering the risk of cardiovascular disease: Reports from medical sources indicate that polyphenols in wine relax the isolated arteries and prevent platelet aggregation, which causes blood clots. (2, 3) Polyphenols in wine have been shown to inhibit the oxidation of low-density lipoprotein (LDL) particles (referred to as bad cholesterol) and increase levels of high-density lipoprotein (HDL) particles (referred to as “good” cholesterol). Oxidation of LDL in blood is associated with the risk of coronary heart disease and myocardial infarction. Polyphenols play a role in lowering the risk of cardiovascular disease and offer protection against the development of certain cancers, diabetes, and neurodegenerative diseases. (2)
General Properties and Benefits of Polyphenols
Polyphenols are powerful, biologically-active chemicals synthesized in most vegetables, herbs, and fruits. The more than 1,000 kinds of polyphenols fall into four main categories: flavonoids, stilbenes, phenolic acids, and lignans. In red wine, up to 90% of the wine’s phenolic content falls under the classification of flavonoids. Each category is broken down into subcategories. And subcategories are broken down into subclasses. Some subclasses of phenolic compounds include pigments, tannins, resveratrol, procyanidins, anthocyanins, and quercetin, to name a few. The bitterness in wine directly correlates to the level of phenolic compounds such as procyanidin and tannins.
Flavonols are a ubiquitous class of flavonoids and have a role in pigmentation and color in berries. The main flavonol in red wine is quercetin, which has been associated with decreasing inflammation and inhibiting cell proliferation that can lead to an attenuation of the progression of cancer. Quercetin is also found in Chardonnay; Riesling; Viogner; Sauvignon Blanc; Nebbiolo; Pinot Noir; and Sangiovese, to name a few. Flavonols have been inversely related to aging, obesity, and the occurrence of neurodegenerative diseases, cardiovascular disease, and several types of cancers. (4)
Stilbenes are largely found in grapes and are associated with the beneficial effects of wine. The principal stilbene—resveratrol, found in the skin and seeds of grapes—is characterized by anticancer, antioxidant, and anti-inflammatory properties. Resveratrol is also known for its effectiveness in preventing all stages of the development of cancer cells and suppressing metastasis. (1, 2, 4)
Is Red Wine Better than White Wine?
Fundamentally speaking, red wines are made with red grapes, such as Pinot Noir, Cabernet Sauvignon, etc., and white wines are made with white grapes including Chardonnay, Pinot Grigio, etc. Polyphenols are mainly found in the skins and seeds of grapes. Because all the color in red wine comes from the skins and seeds of the grapes, only wines made with skin intact, such as red wines, contain more beneficial compounds than white wines, in which the skin and seeds of the berries are removed before fermentation.
Side Effects and Suggested Limits
Although moderate consumption of wine, especially red wine, is beneficial to health (thanks to its antioxidant properties), the alarming signs of health issues arise when an excessive amount of alcoholic beverages are consumed. It is the alcohol in wine (about 8 to 15%) that causes health problems.
Alcohol is a toxic chemical; however, it is the byproduct of alcohol metabolism that causes health problems. Alcohol is not digested like food; it can be absorbed directly into the bloodstream from the mouth and most of the absorption occurs from the stomach and small intestine. The liver is the primary organ for alcohol metabolism. When alcoholic drinks, such as wine, are consumed, an enzyme called alcohol dehydrogenase (ADH) converts ethanol into the carcinogenic and toxic metabolite known as acetaldehyde, mainly in the liver. Acetaldehyde can damage both DNA and proteins in the body through a process of oxidation. Another enzyme, called aldehyde dehydrogenase (ALDH), metabolizes toxic acetaldehyde to nontoxic acetate, which can be broken down into carbon dioxide and water, and is then excreted.
In healthy people, blood circulates through the body in 90 seconds, thereby allowing alcohol to affect your brain and all other organs in a short amount of time. The full effects of a drink are felt within 15 to 45 minutes, depending on the speed of absorption. Elimination of alcohol from the body is slow and takes several hours.
Studies show that drinking alcohol more than the recommended amount can have serious, long-term consequences, including cancer and liver disease. (1) Alcohol, even in small amounts, is linked to a higher risk of breast cancer in women and a risk factor for cancers of the mouth, throat, and liver. (1) Even people who drink moderately are about 14% more likely to have a stroke compared with those who don’t drink at all. (1)
Federal health guidelines recommend that if you drink alcohol, do so in moderation, meaning no more than one to two drinks per day for men and only one drink per day for women. (1) One drink is equal to 5 ounces (148 mL) of wine.
Alternatives to Wine
Although polyphenols in red wine have been shown to have health benefits, wine isn’t the only drink or food with high levels of polyphenols. All plants produce phytochemicals through photosynthesis. Most fruits and vegetables are high in polyphenols. For example, pomegranates, blueberries, cherries, strawberries, blackberries, and grapes are known to have a high content of polyphenols. Fruits like grapes, apples, pears, cherries, and berries contain up to 200–300 mg polyphenols per 100 grams fresh weight. Polyphenols are also abundant in spinach, broccoli, carrots, chili peppers, red cabbage, onions, and beans. Cocoa, the main ingredient in dark chocolate, is high in polyphenols. Resveratrol is naturally produced in peanuts, blueberries, and cacao.
Grape juice and pomegranate juice contain polyphenols in significant amounts. For example, pure pomegranate juice contains 66 mg/100 ml of polyphenols. The average total polyphenol content is 216 mg/100 ml for red wine, 32 mg/100 ml for white wine, and 82 mg/100 ml of phenols in rosé wine.
Summary
Studies show that drinking a moderate amount of wine has some health benefits such as reducing the risk of cardiovascular diseases, increasing HDL levels, and decreasing inflammation. The problem with alcohol consumption arises when an excessive amount of alcoholic beverages is consumed. Red wine has been shown to have health benefits, but it isn’t the only drink with high levels of polyphenols.
References:
(1) https://pmc.ncbi.nlm.nih.gov/articles/PMC9824172/
(2) https://pmc.ncbi.nlm.nih.gov/articles/PMC2835915/
(3) https://health.clevelandclinic.org/polyphenols
(4) https://pmc.ncbi.nlm.nih.gov/articles/PMC3821578/
