Polyphenols Fight Disease
During winemaking, fermentation, oxygen exposure, and oak barrel aging change the phenolic content of grapes, resulting in a more complex product. (1)
Polyphenols are divided into flavonoids and non-flavonoids, based mostly on chemical structure. Flavonoids include compounds such as catechins, epicatechins, proanthocyanidins, condensed tannins, anthocyanins, and quercetin. The most talked about non-flavonoid is resveratrol, but this category also includes phenolic alcohols and ellagitannins.
Polyphenols are good for our health for several reasons. First, as antioxidants, they reduce the burden of oxidative stress, which is at the root of many diseases. (2) Second, they neutralize free radicals, which are very unstable and damage body tissues through volatile chain reactions. (3) Furthermore, polyphenols help our guts by increasing beneficial bacterial strains such as Lactobacillus and Bifidobacteria.
Is wine healthy, or a health hazard?
Health Benefits of Wine Consumption
Red wine contains more polyphenols than white wine (200 mg per glass vs. 30 mg per glass), as red winemaking also includes the skin of grapes. Although many health benefits have been shown for both types of wine, red wine has consistently been proven more beneficial than other types of alcohol.
Antioxidant/anti-inflammatory effects. Antioxidant and anti-inflammatory effects of wine consumption, not just of individual polyphenols, are probably at the root of red wine’s health benefits. Red wine consumption significantly increased total plasma antioxidant status in both younger and older people in a two-week crossover study. (4) Two glasses of red wine every day for a week improved participants’ antioxidant enzyme expression and activity in blood. (5) In healthy women, red wine decreased the levels of several inflammatory markers and cellular adhesion molecules in another crossover study. (6)
Cardiovascular disease. Red wine was hypothesized as one reason for the “French Paradox,” (7) the supposed “contradiction” of lower cardiovascular disease in France despite higher saturated fat intake. (Read more about the diet–heart myth here). But it seems that drinking red wine does have heart benefits.
After consuming Sicilian red wine for four weeks, inflammatory biomarkers of atherosclerosis were lowered. (14) In a large prospective study, red wine drinkers had significantly lower mortality from coronary heart disease than non-wine drinkers. (15)
Cognitive/brain. The brain consumes 15 to 20 percent of the body’s oxygen, despite its relatively small size, which makes it highly susceptible to oxidative stress. (16) Several studies have shown that moderate wine consumption, with its antioxidant properties, can have positive effects on brain health. In a seven-year follow-up study, moderate wine drinkers performed better than people who consumed other types of alcohol on cognitive tests. (17) In women, alcohol abstainers actually scored lower on the tests than wine consumers! Brain function declined more quickly in nondrinkers than in moderate drinkers, from a review of studies spanning 19 countries. (18) Prospective studies demonstrate lower risks of dementia, Alzheimer’s, and Parkinson’s disease in those who drink red wine regularly. (19, 20, 21, 22, 23)
Gut/microbiome. I have written before about the prebiotic effects of polyphenols, which extend to wine. Two glasses of red wine per day increased levels of beneficial bacteria such as Bifidobacterium and Enterococcus, compared to gin consumption, which showed no benefits. (24) Bacteroides, another beneficial gut bacteria, were positively associated with red wine consumption. (25) Natural wines that aren’t aggressively filtered or fermented with commercial yeast strains contain their own probiotics similar to what you find in fermented vegetables and dairy products.
Cancer. Individually, polyphenols found in wine like resveratrol and anthocyanin demonstrate anticancer activity by inhibiting cancer cell proliferation and inducing cancer cell death. (26, 27, 28) Polyphenol-rich wine may offer similar anticancer benefits. Compared to non-wine drinkers, those who regularly consumed moderate amounts of wine had lower overall cancer mortality. (29) In contrast to beer and liquor drinkers, wine consumers had a 40 percent lower risk for both esophageal and gastric cancers, hinting again that there is something special about wine among alcoholic beverages. (30)
Mortality rate. Wine consumption is linked to overall lower mortality. A large study of nearly 25,000 people from 20 to 98 years old found that those who consumed moderate amounts of wine had lower all-cause mortality compared to non-drinkers. (31) The Copenhagen City Heart Study from Denmark followed more than 13,000 adults for 11 years and found that those who drank three to five glasses of wine per day had a lower risk of dying than both spirit drinkers and alcohol abstainers. (32)
Massive numbers of prospective studies and even some clinical trials demonstrate that moderate wine consumption, especially red wine, has many health benefits, which extend even beyond this list. Wine consumption has also been linked to lower stroke risk, (33) lower risk of type 2 diabetes, (34) and lower incidence of bone fracture in the elderly. (35)
Health Risks of Wine Consumption
Now for the bad news. Red wine isn’t all rainbows and sunshine. Ethanol is a poison and poses some serious health risks.
Glutathione depletion. If you have been following my work for some time, you will know that glutathione is crucial for the detoxification of many harmful substances. Because it is required for detoxing ethanol, alcohol consumption can deplete glutathione, making our bodies more susceptible to toxic substances and disease. (36, 37)
Liver damage. When the liver detoxes ethanol, it is first broken down into acetaldehyde, an even more harmful poison that can stick around if your detox capacity is impaired. If you drink too much, your liver (and other body organs) will suffer. Fatty liver disease, hepatitis, and, after long-term heavy drinking, cirrhosis are all downstream effects of chronic alcohol use. (38)
Addiction. Not everyone who drinks will develop a bad habit, but alcohol can be very addictive. Although less addicting that nicotine and crystal meth, alcohol is more addicting than heroin, amphetamine, cocaine, and caffeine.
Gut disruption. Ethanol can further the symptoms of leaky gut. Alcohol damages the gut and causes changes in the gut microbiome, increasing the absorption of pro-inflammatory endotoxins. (42)
Residual sugar (which fortunately is found only in very, very low doses in biodynamic, natural wines) is detrimental to gut health. Sugar can feed unhealthy microbes and other pathogens, leading to gut dysbiosis. (43)
Breast cancer. Earlier I laid out the evidence for lower cancer incidence in those who drank red wine regularly. However, even at low levels of consumption, alcohol consumption may increase the risk of breast cancer in a dose-dependent manner. (44)
Myriad other health risks are attributed to or related to alcohol consumption. For example, although drinking alcohol can increase HDL, the so-called “good cholesterol,” it simultaneously increases triglyceride levels, which is a risk factor for cardiovascular disease. (45)
Who Should Avoid Alcohol
Now let’s return to the question from the beginning of the article. Is wine healthy, or a health hazard? The answer, I believe, is highly individual and depends on a variety of factors. Alcohol in general, including red wine, may not be a good choice for some people.
Genetics can play a huge role. Alcoholism is a serious illness with a strong genetic component. (46) If there is a history of alcohol abuse in your family, avoiding alcohol altogether is probably the most prudent choice. Those with certain genetic polymorphisms in alcohol and aldehyde dehydrogenases, common in people with East Asian ancestry, may also want to avoid alcohol. These variants put them at higher risks of cancer, liver damage, and more because of their inability to detox aldehyde proficiently. (47)
Sulfur-sensitive people, who are estimated to include 1 percent of the population, (48) shouldn’t drink wine due to the sulfites contained either naturally or added. One thing to keep in mind is that dried fruits often have much higher levels of sulfites than wine. So, if you tolerate dried fruit well but have trouble after drinking wine, it might not be due to the sulfites.
Those who take any medications, prescription or not, should be cautious about any potential interactions with alcohol. Some medications can enhance the effects of alcohol, some can cause extreme drowsiness when combined with alcohol, and others can interfere with or change a medication’s effectiveness.
The CDC states that no safe level of alcohol exists for pregnant women. Although traditionally, French women still drink lightly during pregnancy, and some research has suggested that light drinking may not be problematic for the fetus, (50) I would play it safe here. A baby’s body metabolizes alcohol much more slowly than does an adult’s.
If you suffer from asthma, have a blood disorder, or have liver or detoxification issues, avoiding all alcohol is probably the best choice.
How to Maximize the Benefits and Minimize the Risks
If you aren’t a wine drinker, I see no real reason to start. Instead, eat a variety of rich-colored fruits and vegetables to get a wide mixture of polyphenols. Try to include other fermented foods, like sauerkraut and kefir, into your diet. Cooking with red wine is also an option. The alcohol will evaporate, but beneficial polyphenols will remain to an extent.
If you are a wine drinker, try taking it out of your diet for 30 days. Then, add back in natural, organic wine, at moderate levels to see how you feel. If your sleep and mood are unaffected, then moderate wine consumption is probably doing you more good than harm, in terms of health benefits and enjoyment.