Does Drinking Water Help Fatty Liver? What It Can and Can't Do

TL;DR

• Drinking more water isn’t a proven treatment for fatty liver, and it doesn’t flush fat out of the liver. The studies linking water to lower risk are observational.
• Water’s clear benefit is what it replaces. Soda, juice, sweet tea, sports drinks and alcohol all add to liver fat or liver damage, and water is the easiest swap.
• Most healthy adults can let thirst guide them. If you have cirrhosis with low blood sodium, your hepatologist may limit fluids, so follow their advice.

Drinking water doesn’t directly treat fatty liver, and there’s no good evidence it flushes fat out of the liver. Where water clearly helps people with MASLD (formerly NAFLD) is as a replacement: every glass that takes the place of a soda, juice or alcoholic drink removes sugar or alcohol your liver would otherwise have to deal with.

Here’s what the research shows, how much water you need, and the one situation where more isn’t better.

Does Drinking Water Reduce Liver Fat?

We couldn’t find any clinical trial that tested drinking more water as a treatment for fatty liver. What exists are observational studies, which can show a link but not cause and effect:

• A Chinese population study of 16,434 adults in Tianjin found that men who drank more than 7 cups of plain water a day had 23% lower odds of newly diagnosed fatty liver than men who drank 3 cups or fewer. There was no link in women. The study was cross-sectional, a single snapshot in time.
• A US study of about 3,500 adults with fatty liver from the NHANES survey linked higher plain water intake to lower death rates from any cause, stroke and cancer. Replacing sugary or artificially sweetened drinks with water was linked to lower mortality too.
• A UK Biobank analysis of 123,788 adults, presented at UEG Week 2025 as a conference abstract, estimated that replacing sugary drinks with water was linked to a 12.8% lower risk of developing MASLD, and replacing low- or no-sugar drinks with water to a 15.2% lower risk.

These findings point the same way, but they can’t separate water itself from what it replaces, or from the healthier habits of people who drink a lot of water. The fairest reading is that water is a marker of a better drinking pattern, and that the swap is what matters.

Why Replacing Sugary Drinks and Alcohol Matters

The best evidence for water comes from studies where it was the comparison. In a six-month Danish trial, 47 adults with overweight drank 1 liter a day of regular cola, semi-skimmed milk, diet cola or water. Liver fat rose 132–143% more in the regular cola group than in the other three groups. Our article on soda and fatty liver covers this research in more detail.

That’s why liver guidelines focus on drinks:

• Sugary drinks. The 2024 European liver guideline recommends that adults with MASLD avoid sugar-sweetened beverages. The NIDDK advises avoiding drinks with large amounts of simple sugars, especially fructose, which it notes is found in sweetened soft drinks, sports drinks, sweetened tea and juices.
• Alcohol. The European guideline discourages alcohol for people with fatty liver and says it should be stopped completely with advanced fibrosis or cirrhosis. See is alcohol safe with fatty liver.
• Coffee. Plain coffee is the one drink with good liver evidence of its own. See is coffee good for fatty liver.

Water may also help with weight loss, the most effective treatment for fatty liver. In a 12-week trial of 48 adults aged 55 to 75 with overweight or obesity on a reduced-calorie diet (Dennis et al., Obesity, 2010), those who drank 500 ml (about 17 ounces) of water before each meal lost about 2 kg (4.4 lb) more than those who didn’t. A UK trial of 84 adults with obesity (Parretti et al., Obesity, 2015) found a similar but smaller effect, about 1.3 kg (2.9 lb) more over 12 weeks. Both were small, but drinking a glass of water before meals is an easy habit to try.

How Do Common Drinks Compare?

Here’s how much sugar common drinks contain per 12-ounce serving:

Drink (12 fl oz)	Calories	Sugars
Tap water	0	0 g
Club soda or plain sparkling water	0	0 g
Black tea, brewed, unsweetened	4	0 g
Coconut water, unsweetened	66	14 g
Sports drink, lemon-lime	117	22 g
Orange juice	183	31 g
Apple juice, unsweetened	171	36 g
Cola, regular	155	37 g

Source: USDA FoodData Central (SR Legacy).

For context, the FDA’s Daily Value for added sugars is 50 g. A single can of cola uses up about three-quarters of it. Juice has no added sugar, but its sugar arrives without the fiber of whole fruit, and the European guideline recommends fruit rather than juice. Coconut water sits in the middle; see is coconut water good for fatty liver for the details.

How Much Water Should You Drink?

There’s no special water target for fatty liver. The best general reference is a 2004 report from the Institute of Medicine of the National Academies:

• Adequately hydrated women take in about 2.7 liters (91 ounces) of total water a day, and men about 3.7 liters (125 ounces). That’s total water, from all drinks and foods.
• About 80% comes from water and other beverages, “including caffeinated beverages,” and about 20% from food.
• The panel deliberately didn’t set a “how many glasses” rule. It concluded that most healthy people stay hydrated by drinking with meals and “letting their thirst guide them.”
• People who are very active or live in hot climates may need more.

In practice, if water becomes your default drink with meals and between them, most people land in a healthy range without counting. If you like a target, an app like Liverly can track water alongside coffee so you can see your daily pattern.

What If You Have Cirrhosis?

Fluid advice is different with advanced liver disease, so don’t apply general “drink more water” tips without checking.

• Fluid restriction is not routine. A 2024 review by liver specialists says only patients with severe low blood sodium (below 125 mEq/L) should be put on a fluid restriction.
• Sodium is the main tool for fluid buildup. For ascites, limiting sodium (usually with diuretics) does more than limiting water. Our cirrhosis diet guide explains the sodium targets.
• Your plan is personal. Blood sodium, kidney function, diuretics and heart health all affect how much fluid is right for you.

If your hepatologist has given you a fluid limit, follow it, even if it differs from what you read here.

Easy Ways to Drink More Water

• Make water the default with meals. Order it when eating out and skip free soda refills.
• Keep a bottle in sight. At your desk, in the car, on the kitchen counter.
• Add flavor without sugar. Lemon, lime, cucumber, mint, a few crushed berries or slices of fresh ginger.
• Use sparkling water to replace soda. It keeps the fizz without the sugar.
• Step down gradually. If you drink soda daily, go to a smaller size, then half soda and half sparkling water, then plain sparkling water.
• Brew unsweetened iced tea by the pitcher for a change from plain water.
• Have a glass before meals. It’s a simple habit with some evidence for helping weight loss.

The Bottom Line

Drinking water doesn’t directly treat fatty liver, and it doesn’t flush fat out of the liver. Observational studies link higher water intake to lower fatty liver risk and better survival in people with MASLD, but they can’t prove water itself is the reason.

What is clear is that water is the best replacement for the drinks that do harm a fatty liver: soda, juice, sweet tea, sports drinks and alcohol. Make water your default, let thirst guide how much you drink, keep coffee and tea unsweetened, and if you have cirrhosis, follow your hepatologist’s fluid and sodium advice.

Sources

• National Academies: Report Sets Dietary Intake Levels for Water, Salt, and Potassium to Maintain Health and Reduce Chronic Disease Risk (2004).
• Wang X, et al. Higher plain water intake is related to lower newly diagnosed nonalcoholic fatty liver disease risk: a population-based study. European Journal of Clinical Nutrition. 2021.
• Zhao N, et al. Association of plain water intake with risk of all-cause and cause-specific mortality in individuals with NAFLD or MASLD. Frontiers in Nutrition. 2024.
• Maersk M, et al. Sucrose-sweetened beverages increase fat storage in the liver, muscle, and visceral fat depot: a 6-mo randomized intervention study. American Journal of Clinical Nutrition. 2012.
• Kwong AJ, Norman J, Biggins SW. Management of ascites and volume overload in patients with cirrhosis. Clinical Liver Disease. 2024.

This article is for informational purposes only and is not medical advice. Talk to your doctor or hepatologist about your specific situation.