There is no amount of wine that is completely risk-free, but official U.S. dietary guidelines define moderate drinking as up to one drink per day for women and up to two for men. One standard drink of wine is 5 ounces at 12% alcohol by volume, which is smaller than most people pour at home. Where you fall on the risk spectrum depends on your age, sex, and which health outcomes you care about most.
What Counts as One Glass
A standard glass of wine is 5 ounces, roughly the size of a small yogurt container. That’s based on a typical 12% alcohol-by-volume table wine. Many popular reds and whites now clock in at 14% or 15%, which means the same pour delivers more alcohol than the guidelines assume. If you’re drinking a bold Zinfandel or an oaked Chardonnay at 14.5%, your “one glass” is already overshooting.
A dry table wine contains about 1 to 2 grams of sugar per 5-ounce serving and roughly 120 to 130 calories. Sweet and dessert wines like Port or Sauternes pack around 8 grams of sugar in a smaller 3.5-ounce pour. The caloric difference adds up quickly for daily drinkers: two glasses of dry red per night amounts to roughly 1,800 extra calories per week.
The Official Limits
The CDC and the U.S. Dietary Guidelines for Americans set the threshold at one drink or fewer per day for women and two or fewer for men. These aren’t targets to hit. They’re upper limits for people who already drink. If you don’t drink, no health authority recommends starting.
For adults over 65, the window narrows further. The National Institute on Alcohol Abuse and Alcoholism recommends no more than 7 drinks per week and no more than 3 on any single day for healthy older adults who take no medications. After 65, lean body mass and total body water decrease, and metabolism slows. Alcohol stays in your system longer, so the same glass of wine produces a higher blood alcohol level than it would have a decade earlier.
The Heart Health Debate
For years, moderate wine drinking was linked to lower rates of heart attacks and cardiovascular death. Large epidemiological studies consistently found a J-shaped curve: people who drank one to two glasses a day had lower cardiovascular risk than both nondrinkers and heavy drinkers. One analysis found that cardiovascular risk dropped progressively with intake up to about three to four standard drinks per day, with reductions approaching 50% at the higher end. The pattern held for stroke, heart failure, and even for people who had already survived a heart attack.
The minimum risk for death from all causes sits at about one drink per day for women and one to two for men. Beyond three to four drinks daily for men or two to three for women, overall mortality climbs back to the same level as nondrinkers, then keeps rising.
This picture has come under serious challenge. The World Health Organization issued a statement in 2023 declaring that no level of alcohol consumption is safe for health, arguing that any cardiovascular benefit is offset by the cancer risk alcohol carries. The WHO’s position is that the apparent protective effect may partly reflect flaws in how studies chose their comparison groups, since “nondrinkers” in many studies included former heavy drinkers who quit because of illness. Still, the majority of published cohort studies continue to show lower all-cause mortality among moderate drinkers compared to lifelong abstainers, even in analyses that account for these methodological concerns.
Cancer Risk Starts Early
This is where the conversation shifts sharply. The U.S. Surgeon General’s advisory on alcohol and cancer lays out numbers that may surprise moderate drinkers. Women who consume up to about one drink per day have a 10% higher relative risk of breast cancer compared to nondrinkers. At more than two drinks per day, that increase jumps to 32%.
Mouth cancer risk rises even more steeply. About one drink per day is associated with a 40% increase in relative odds of mouth cancer. At roughly two drinks per day, that nearly doubles to a 97% increase. These are relative risk figures, so the absolute numbers remain small for any individual, but the trend is clear and dose-dependent. There is no identified threshold below which alcohol’s cancer-promoting effects don’t operate. The risk begins with the first drink.
Liver Risks Differ by Sex
Women face measurably higher liver risk at lower drinking levels than men. A systematic review and meta-analysis published in the American Journal of Gastroenterology found that just one drink per day increased the risk of liver cirrhosis in women, but not in men. At one to two drinks daily, women already showed a substantially elevated risk.
For both sexes, risk escalated dramatically at higher levels. At five or more drinks per day, women’s cirrhosis risk was roughly 12 times that of long-term abstainers, climbing to nearly 25 times at seven or more drinks daily. Men’s risk followed a similar trajectory but started from a lower baseline. The practical takeaway: women metabolize alcohol differently and accumulate liver damage faster, which is one reason the recommended limits are lower.
Effects on the Brain
A large study using brain imaging data from the UK Biobank found that negative effects on brain structure were detectable in people consuming an average of just one to two standard drinks per day. These effects included reductions in gray matter volume and changes in white matter integrity. The associations grew stronger as intake increased, suggesting there isn’t a clear “safe” zone for brain health even at moderate levels.
Earlier research had already linked moderate drinking in middle-aged and older adults to lower total brain volume and gray matter loss in frontal and parietal regions, areas involved in decision-making, attention, and spatial awareness. For people concerned about long-term cognitive sharpness, these findings are worth weighing alongside the cardiovascular data.
Red Wine vs. White Wine
Red wine gets special attention because of its polyphenol content. A typical glass of red wine contains about 200 milligrams of polyphenols, plant-based compounds with antioxidant properties. A glass of white wine contains only about 30 milligrams. The difference comes from the winemaking process: red wine ferments with the grape skins and seeds, which is where most of these compounds live.
Resveratrol, the most discussed polyphenol in red wine, has been shown in lab and small human studies to promote nitric oxide production in blood vessels, which helps keep arteries flexible. White wine and beer did not produce the same effect in these experiments. This is the basis for the “French Paradox,” the observation that French populations had relatively low heart disease rates despite a diet rich in saturated fat, possibly because of regular red wine consumption.
That said, you would need to drink far more red wine than is advisable to get a therapeutic dose of resveratrol. The polyphenol advantage of red wine does not change the alcohol-related risks for cancer, liver disease, or brain health. If you’re choosing between red and white for health reasons, red has a modest edge, but the alcohol itself remains the dominant factor.
Putting the Tradeoffs Together
The honest answer is that “safe” depends on what risk you’re measuring. At one glass per day for women or one to two for men, cardiovascular risk appears to decrease. At those same levels, cancer risk measurably increases, liver risk rises for women, and brain volume effects are already detectable. The WHO says no amount is truly safe. The U.S. guidelines say moderate drinking is an acceptable personal choice within defined limits.
Your individual calculation depends on your family history, your sex, your age, and which risks matter most to you. A 40-year-old woman with a strong family history of breast cancer faces a different equation than a 60-year-old man with cardiovascular risk factors. The less you drink, the lower your overall risk profile. If you do drink, staying within one glass for women and two for men, measured carefully at 5 ounces, keeps you within the range where the data is least alarming.