Dry January and Weight Loss: What Changes When You Stop Drinking for a Month
Quick answer: A month without alcohol removes every drinking calorie from your week, and for a regular drinker that adds up. Six 500 ml lagers over a weekend come to about 5,850 kcal across January, roughly 1.7 lb on paper. A glass of wine on five evenings a week is about 2,650 kcal, or three quarters of a pound. In a London study of regular drinkers, a dry month brought weight down by about 1.5 %. Whether you see that on the scale depends on what replaces the drinks: soda water keeps the saving, while dessert, juice and extra snacks take it back.
What your usual drinking adds up to over January
Alcohol calories are easy to miss because drinks rarely carry a label. Per-drink numbers are in our full table of calories in beer, wine and cocktails; here they are added up over the 31 days of January for four common patterns.
| Usual pattern | Per week | Over January (31 days) | On paper* |
|---|---|---|---|
| 1 glass of dry red (150 ml, ~120 kcal) on 5 evenings | 600 kcal | ~2,650 kcal | ~0.75 lb (0.35 kg) |
| Half a bottle of wine (~315 kcal), 3 evenings | 945 kcal | ~4,200 kcal | ~1.2 lb (0.55 kg) |
| 3 × 500 ml lager (~220 kcal) on Friday and Saturday | 1,320 kcal | ~5,850 kcal | ~1.7 lb (0.75 kg) |
| 2 mojitos (~220) + 2 gin and tonics (~165) on Friday and Saturday | 1,540 kcal | ~6,800 kcal | ~1.9 lb (0.9 kg) |
*Using the rough rule that a pound of body fat is about 3,500 kcal. Over a single month it's a usable estimate, as long as nothing else in your eating changes.
Two things stand out. First, the weekend pattern matters more than the daily glass: two nights of beer or cocktails cost more than wine five nights a week. Second, the totals are real but modest. A dry month is not a crash diet; it's a steady deficit of 100–250 kcal a day, which is close to what most people would choose on purpose anyway.
What the studies found
Most evidence on Dry January comes from people who signed up for it, so it shows what happens to volunteers, not to everyone. Three findings are worth knowing.
Weight and blood markers. A study at the Royal Free Hospital in London followed 94 healthy regular drinkers who stopped for a month and 47 who carried on. The abstinence group had been drinking about 258 g of alcohol a week, or around 18 US standard drinks. After the dry month their weight fell by about 1.5 %, blood pressure by about 6 % and insulin resistance by about a quarter; the drinking group showed no significant change. The authors report that the changes were not explained by shifts in diet, exercise or smoking. For an 80 kg (176 lb) person, 1.5 % is about 1.2 kg (2.6 lb). Lighter drinkers should expect less, because they have fewer calories to remove.
Self-reported changes. In the University of Sussex survey of more than 6,000 Dry January participants in 2019, 86 % said they had saved money, 70 % that they slept better, 66 % that they had more energy and 54 % that they had lost weight. These are participants' own answers, not measurements, but the direction matches the study above.
What happens afterwards. A University of Sussex study that followed participants for six months found they drank on fewer days, drank less per drinking day and got drunk less often than before the challenge. The change was also seen in people who didn't complete the full month. A dry month seems to reset habits as much as it removes calories.
Where the calories come back
The table above assumes nothing else changes. In practice, three things decide how much of the saving you keep.
What goes in the glass instead. Soda water, sparkling water with lime, black coffee and tea cost nothing. Other swaps do: non-alcoholic beer is 60–90 kcal per 330 ml because the sugar that would have become alcohol is still in it, a 150 ml glass of cola is about 65 kcal, and juice-based mocktails can be close to a real cocktail. Swapping three 500 ml lagers for three 500 ml alcohol-free beers keeps roughly half of the saving.
What used to come with the drinks. Crisps, nuts and late-night food often travel with alcohol. Our New Year's Eve party guide counts a typical evening of party snacks at about 1,310 kcal before the first glass. If the drinks go but the snack bowl stays, much of the deficit disappears.
The sweet tooth. Many people notice they want more dessert or chocolate in the first weeks without alcohol. That's worth planning for rather than fighting: one square of chocolate is a far smaller number than the glass of wine it replaces, but a whole bar is not.
How to make the month count
- Weigh in during the first week and use the average of a few mornings as your starting point. January 1, 2027 is a Friday, so the first full week starts on Monday, January 4. If the scale is up after the holidays, part of it is water from salty food; our January restart guide explains how to read it.
- Log your normal drinking for one past week before you stop. It turns "I don't drink much" into a number, and it's the number you're saving.
- Pick your default drink for evenings and nights out before the first one comes up: soda water with lime, alcohol-free beer, or tea.
- Keep eating as usual otherwise. The dry month already gives you a deficit. Stacking a strict diet on top makes both harder to keep.
- Check in at the end of January with the same weigh-in routine, and decide what you want your drinking to look like in February. The Sussex follow-up suggests that's where the lasting change is.
A safety note: Alcohol Change UK, the charity that runs Dry January, says the challenge is not suitable for people who are clinically dependent on alcohol, because stopping suddenly can be dangerous. If you get shaky, sweaty or anxious when you go without a drink, speak to a doctor before you stop. For guidance on how much is safe to drink, follow your national health guidelines.
How to log a dry month
Logging matters most for the drinks that still have calories. Scan the barcode on a can of alcohol-free beer and the pack's serving size is kept. A quick voice note works for drinks at a bar: "two alcohol-free beers and a lemonade". Soda water and sparkling water can go in as water, so your water total grows rather than your calories. If you forget a night out, add it to that day from the calendar the next morning.
To see the effect, compare two weeks: your last ordinary drinking week and a dry one. The difference in daily calories is your real saving, after any extra snacks or desserts. If it's smaller than the table above suggests, the drinks you replaced them with are usually the reason.
FAQ
How much weight can you lose in Dry January? It depends on how much you usually drink. Regular drinkers can save 4,000–7,000 kcal over the month, about 1–2 lb on paper. In a London study of regular drinkers, weight fell by about 1.5 % after a dry month. Light drinkers save less, and extra snacks or sweet drinks can cancel the difference.
Why am I not losing weight after I stopped drinking? Usually because the calories moved elsewhere: alcohol-free beer, juice, mocktails, desserts or the snacks that came with drinks. Log a full week and compare it with a week of your old drinking. Post-holiday water weight can also hide a real loss in the first days of January.
Are alcohol-free beer and mocktails low in calories? Lower, not zero. Alcohol-free beer is 60–90 kcal per 330 ml, against 140–150 for a standard lager. Mocktails made with juice or syrup can be close to the cocktail they copy. Soda water, sparkling water and diet mixers are the zero-calorie options.
Does Dry January change drinking after January? In a University of Sussex study, participants drank on fewer days, drank less per occasion and got drunk less often six months later. The effect also appeared in people who didn't finish the full month.
Should I cut calories as well during Dry January? It's not necessary. Removing alcohol already creates a deficit for most regular drinkers. Keep your meals as usual, watch what replaces the drinks, and decide on further changes after the month.
Is Dry January safe for everyone? Not for people who are clinically dependent on alcohol. Alcohol Change UK advises them not to stop suddenly and to get medical advice first, because sudden withdrawal can be dangerous.
Data: Mehta G et al., Short-term abstinence from alcohol and changes in cardiovascular risk factors, liver function tests and cancer-related growth factors: a prospective observational study, BMJ Open 2018;8:e020673; de Visser RO et al., Voluntary temporary abstinence from alcohol during "Dry January" and subsequent alcohol use, Health Psychology 2016;35:281–289; de Visser RO, Evaluation of Dry January 2019, University of Sussex, as reported by Alcohol Change UK; Alcohol Change UK, Dry January challenge policies. Per-drink calories from our alcohol guide. Checked October 2026.
Related: Calories in alcohol · After the holidays: restart tracking · Calorie deficit for weight loss
CalMePlease logs a dry month without fuss: scan the alcohol-free beer, say "two lemonades" in a voice note, and add a forgotten night out from the calendar. Free on the App Store.
