Does drinking wine every night cause weight gain?

It can. A 5 oz glass of dry wine has about 120 to 125 calories, and most home pours are bigger, so a nightly glass or two adds 900 to 2,000 calories a week before the cheese and late snacks that tend to come with it. Large studies found that light drinkers didn't gain more than non-drinkers on average, but heavier drinking was linked to weight gain. Whether your nightly wine shows on the scale depends on how much you pour, what you eat with it, and how it affects your sleep and next-day appetite.

Below: the calories by pour and by week, the four ways nightly wine adds weight, what the research says, why it can feel worse after 40, and a 3-week way to test it on yourself without giving wine up.

Calories in wine, by glass

Figures are rounded from USDA FoodData Central values for table wines; strength changes them most. Alcohol has 7 calories per gram, so a 14% wine has more calories than an 11% one even when both are dry.

What a nightly habit adds up to

The glass size matters more than the wine. A 5 oz pour is a small glass; many people pour 6 to 9 oz at home without noticing. Our guide to standard drinks in a bottle of wine shows how to measure yours.

Those numbers don't turn into weight one for one. The body adjusts, and the old "3,500 calories is a pound" rule overstates long-term change. But a steady extra 900 to 2,000 calories a week, kept up for months, is the kind of surplus that slowly moves the scale, especially if you don't eat less to make room for it. The NIH Body Weight Planner lets you test your own numbers.

Four ways nightly wine adds weight

1. The calories themselves

Wine calories don't fill you up. People rarely eat less at dinner because they had a glass, so the wine is added on top of the day's food.

2. Your body burns the alcohol first

Your body can't store alcohol, so it uses it for fuel as soon as it can. While it does, it burns less fat. In a controlled study (Siler and colleagues, 1999), alcohol cut the body's fat burning sharply for several hours. The fat from that evening's meal is then more likely to be stored.

3. Wine makes you eat more

Alcohol lowers restraint and can sharpen your appetite. In a 2015 study at Indiana University, women given alcohol ate more at the meal that followed than when given a placebo, and brain scans showed stronger responses to food smells. In real life it looks like the cheese board while you cook, a second helping, or chips at 10 p.m. Those snacks often carry more calories than the wine.

4. Worse sleep, hungrier tomorrow

Wine helps you fall asleep but breaks up the second half of the night (see alcohol and sleep quality). Short or poor sleep is linked to more hunger and more snacking the next day, and less energy to move. A nightly glass can affect your weight through the day after, not only the evening.

What the research says

• Light drinking, on average, isn't linked to gain. In the US Women's Health Study (Wang and colleagues, 2010), about 19,000 women who started at a normal weight were followed for about 13 years. Those who drank lightly to moderately gained a little less weight on average than non-drinkers, and red wine showed the strongest link of that kind.
• Heavy drinking is. A review of the research (Traversy and Chaput, 2015) found light to moderate drinking was mostly not linked to weight gain, while heavy drinking was, and binge drinking especially.
• Those studies show links, not causes. Light drinkers in such studies often differ in other ways (diet, activity, income). They don't show that wine helps weight; they show that a little wine, in people who already keep their weight steady, isn't the main driver.
• Your pour may be "heavy" without feeling like it. Two large glasses a night is about 3 to 4 standard drinks, which for a woman is past the heavy-drinking line of 8 a week by Wednesday.

For the general picture of drinks and weight across beer, cocktails and wine, see will drinking less help me lose weight?

Is "wine belly" real?

Partly. Alcohol doesn't send fat to your waist on its own; people tend to gain weight all over. But heavier drinking is linked to more fat around the middle in several studies, and after menopause women tend to store more fat at the waist anyway. The fix is the same: less wine and fewer evening snacks, not a special food or drink.

Why it seems to hit harder after 40

• Lower calorie needs. Most people burn fewer calories as they lose muscle with age, so the same glass makes up a bigger share of the day.
• Menopause. Hormone changes shift where fat is stored, and sleep often gets lighter, which wine makes worse.
• Habit length. A nightly glass that's been there for 10 years has added up quietly; the pour has often grown too.

Red, white or rosé: does it matter for weight?

Very little. Dry reds, whites and rosés have similar calories per glass, and the difference comes mostly from strength. A 14.5% Zinfandel has more than an 11% Pinot Grigio. Sweet wines add sugar on top. If you're choosing for weight, pick a lower-strength dry wine, and keep the glass small.

Eight changes that keep the wine but cut the gain

1. Measure your pour once. Pour your usual glass into a measuring cup. If it's 8 oz, a smaller glass alone cuts about 40%.
2. Make two nights a week wine-free. That's 250 to 400 fewer calories a week at one glass a night, and the easiest step to keep.
3. Drink it with dinner, not before. Wine while cooking is when the snacking starts.
4. Water first. A big glass of water or sparkling water before the wine, and one alongside it.
5. Try a spritzer. Half wine, half soda water: half the calories, the same glass in your hand.
6. Lower-alcohol wine. Wines at 9 to 11% have fewer calories; alcohol-free wines have far fewer (often 20 to 60 a glass, check the label).
7. Close the kitchen. Decide that the wine ends with dinner, and brush your teeth after.
8. Buy one bottle at a time. Wine in the house gets drunk. Our guide how to cut back on drinking wine has more on this.

A 3-week test you can run yourself

Compare the average of each week's weights, not single days; water weight swings by 1 to 3 pounds. Many people find the snacks and sleep changed more than the scale did in 3 weeks, and that's the early sign it's working.

If the hard part is the moment you pour, not the wine itself, our free 2-minute drinking pattern quiz finds the cue behind it. For the nightly pull itself, see craving wine every night.

When to talk to a doctor

• You're gaining weight without a clear reason, or losing it without trying.
• You can't skip wine for a night, or feel shaky, sweaty or anxious when you do. Stopping suddenly after heavy daily drinking can be dangerous; a doctor can help you cut down safely.
• You have high blood pressure, diabetes, fatty liver or take medicines that don't mix with alcohol (see wine every night and blood pressure).

The free, confidential SAMHSA National Helpline is open every day: 1-800-662-4357.

Questions people ask

Will one glass of wine a night make me gain weight?

Not necessarily. One 5 oz glass is about 125 calories, about 875 a week. If the rest of your eating stays the same and you don't snack with it, many people's weight holds steady. A bigger pour, or snacks alongside, is what usually tips it.

Will I lose weight if I stop drinking wine every night?

Many people do, if they don't replace the wine with other evening calories. Expect sleep and appetite to change first and the scale more slowly.

Is red wine less fattening than white?

No. Dry reds and whites have similar calories; strength makes the difference.

Does wine have a lot of sugar?

Dry wine has very little, usually 1 to 2 grams a glass. Most of its calories come from alcohol. Sweet and dessert wines have much more.

Is wine before bed worse for weight?

Late wine tends to bring late snacking and worse sleep, both linked to weight. Having it with an earlier dinner is better.

How long after cutting back does weight change?

Water weight and bloating can drop within a week or two; fat loss from the calories saved takes longer, usually showing over 1 to 3 months.

More on wine and drinking less: all our drink less guides.

Sources: USDA FoodData Central, table wine, red and white. Wang L, Lee IM, Manson JE, Buring JE, Sesso HD, "Alcohol consumption, weight gain, and risk of becoming overweight in middle-aged and older women", Archives of Internal Medicine, 2010. Traversy G, Chaput JP, "Alcohol Consumption and Obesity: An Update", Current Obesity Reports, 2015. Siler SQ, Neese RA, Hellerstein MK, "De novo lipogenesis, lipid kinetics, and whole-body lipid balances in humans after acute alcohol consumption", American Journal of Clinical Nutrition, 1999. Eiler WJA et al., "The apéritif effect: alcohol's effects on the brain's response to food aromas in women", Obesity, 2015. NIH Body Weight Planner. Sleep Foundation, "Alcohol and Sleep". SAMHSA National Helpline, 1-800-662-4357.