How to Lose Water Weight (Safely)

Quick Answer: You can reduce temporary water retention by cutting excess sodium, keeping carbs consistent, staying well-hydrated, and eating potassium-rich foods. Skip the "water pills" unless your doctor prescribes them. And remember—water loss isn't fat loss. For lasting results, you still need a sustainable calorie deficit.

What Water Weight Actually Is

You step on the scale Monday morning: down two pounds. By Wednesday, you're up three. What happened? Probably nothing—at least nothing related to fat. What you're seeing is water weight, and it can swing by several pounds in a single day.

Water weight is exactly what it sounds like: fluid your body is holding in tissues or alongside stored carbohydrate. Your muscles store energy as glycogen, and each gram of glycogen brings along roughly three grams of water.^{1, 2, 3} So when you eat more carbs than usual—say, pasta night followed by Sunday brunch—your glycogen stores top off and you retain more water. The scale goes up, but you haven't gained fat.

This is why people see dramatic early results on low-carb diets. They're not losing fat faster; they're depleting glycogen and shedding the water that came with it. It's also why the scale can be so frustrating when you're doing everything right—your fat loss might be happening, but water fluctuations are hiding it.

Why You're Retaining Water

The most common culprit is sodium. Restaurant meals, packaged foods, and takeout are often loaded with it, and when you eat more sodium than usual, your body holds onto water to maintain the right concentration in your blood.⁴ That bloated feeling after Chinese takeout isn't in your head—it's your body responding to a sodium spike.

Carb swings matter too. If you've been eating low-carb and then have a high-carb day, expect the scale to jump. It's not fat; it's glycogen refilling and bringing water along for the ride.^{1, 2} This is temporary and will normalize once your eating patterns stabilize.

For women, the menstrual cycle adds another layer. Hormonal shifts can cause fluid retention, particularly in the week before your period.⁵ If you're tracking weight for fat loss, it helps to compare the same point in your cycle month-to-month rather than day-to-day.

Other temporary causes include travel (sitting for long periods, cabin pressure, dehydration), heat exposure, starting a new workout routine (inflammation from muscle soreness), and certain medications. Most of these resolve on their own within a few days.

That said, persistent or severe swelling—especially if it's one-sided, painful, or comes with shortness of breath—can signal something more serious like heart, kidney, or liver issues. If that describes your situation, see a doctor rather than trying to manage it yourself.⁶

How to Reduce Water Retention Safely

The good news is that most water retention responds well to simple changes. You don't need supplements, detox teas, or anything extreme.

Start with sodium. The American Heart Association recommends staying under 2,300 mg per day, and many people feel better closer to 1,500 mg.⁴ The easiest way to cut sodium is to cook more at home—restaurant and packaged foods are where most excess sodium hides. Check labels, choose low-sodium options when available, and season with herbs, spices, citrus, and vinegar instead of salt. If cooking every meal feels unrealistic, portion-controlled meal plans with balanced sodium can help you stay consistent without the effort.

Rather than swinging between very low-carb and very high-carb days, try keeping your carb intake relatively consistent. Pick a range that works for your goals and stick with it for a week. This lets your glycogen levels stabilize, which means fewer water weight swings obscuring your progress.^{1, 2}

Drink enough water—but don't overdo it. This sounds counterintuitive, but staying well-hydrated actually helps your body release excess fluid rather than hold onto it. Most adults do well with around 3.7 liters per day for men and 2.7 liters for women, including water from food.^{7, 8} Pale yellow urine is a simple indicator that you're in a good range.⁹

Potassium-rich foods help counter sodium's effects on fluid balance. Think beans, potatoes, leafy greens, bananas, citrus, and yogurt.¹⁰ These foods show up repeatedly on lists of the healthiest options for weight loss too—for a deeper dive, see our complete guide to the best foods for weight loss. One note: if you have kidney disease or take certain medications, check with your doctor before loading up on potassium.¹¹

Movement helps. Walking, light cardio, and general activity improve circulation and can reduce fluid pooling in your legs and feet. You'll also sweat out some water during exercise—just remember to rehydrate afterward.

Finally, protect your sleep. Poor sleep affects hormones that regulate fluid balance, appetite, and stress—all of which can contribute to water retention.¹² Limiting caffeine to at least six hours before bed and keeping alcohol moderate will help you sleep better and retain less water.

What About Diuretics?

Skip the "water pills" unless your doctor prescribes them for a specific medical condition. Over-the-counter and prescription diuretics can cause electrolyte imbalances and other problems when used for weight loss.¹³ They're designed to treat conditions like high blood pressure and heart failure—not to make you look leaner for a beach trip. If you're tempted to use them, that's a sign you're focusing too much on the scale and not enough on sustainable habits.

A Simple 24-48 Hour Reset

If you have an event coming up and want to minimize bloating, here's a gentle approach that won't backfire.

For meals, focus on lean protein, vegetables, and a moderate portion of whole grains or starchy vegetables. Keep sauces simple—lemon juice, fresh herbs, a light drizzle of olive oil. Aim for roughly 400-600 mg of sodium per meal, which means cooking at home and avoiding anything processed, cured, or restaurant-prepared.

Keep your carb intake steady rather than crashing low. Going very low-carb will drop water weight quickly, but you'll also feel flat and tired—and you'll regain it all the moment you eat normally again.

Sip water throughout the day and include hydrating foods like berries, cucumber, citrus, and yogurt. Stop drinking fluids about two to three hours before bed so you're not up all night.

Get some easy movement—a walk after meals, light stretching, nothing intense. And prioritize sleep: aim for seven to nine hours and skip the alcohol, which disrupts sleep quality and contributes to water retention.

This won't produce dramatic results, but it will help you feel your best without any extreme measures that leave you feeling worse afterward.

The Bigger Picture

Water weight fluctuations are normal. Everyone experiences them. The problem is when we let the scale dictate how we feel about our progress—or worse, when we chase water weight loss thinking it's fat loss.

If your goal is actually losing fat, water weight management is just one small piece. You still need a sustainable calorie deficit, adequate protein, and consistent habits over time. For help with the nutrition side, our guides on setting calorie goals and portion control vs. calorie counting are good starting points. If you're hitting a plateau on keto, this troubleshooting guide addresses the unique water weight dynamics of low-carb eating.

The scale is one data point, not the whole story. Trends over weeks matter more than any single weigh-in.

Frequently Asked Questions

How fast can I lose water weight?

You might see the scale drop within 24-72 hours as sodium levels normalize and glycogen stabilizes. Just remember this isn't fat loss—it's fluid. Keep your habits steady to see true fat-loss trends emerge over time.

Should I cut carbs to drop water weight?

Going very low-carb will deplete glycogen and the water stored with it, which shows up as quick weight loss on the scale. This can be useful if you have a specific weigh-in, but it's not necessary for fat loss and most people do better keeping carbs consistent rather than cycling between extremes.¹

Which foods help reduce water retention?

Potassium-rich foods like beans, potatoes, leafy greens, bananas, and yogurt help balance out sodium's effects. Minimally processed whole foods in general will help because they're naturally lower in sodium. If you have kidney disease or take certain medications that affect potassium levels, talk to your doctor before making big changes.^{10, 11}

When should I see a doctor?

If your swelling is new, one-sided, painful, or persistent—or if it comes with shortness of breath, chest pain, or rapid unexplained weight gain—get medical attention. These could be signs of heart, kidney, liver, or clotting issues that need professional evaluation.⁶

References

1. Murray B. Fundamentals of glycogen metabolism—~3 g water per 1 g glycogen. PMC.
2. Fernández-Elías V, et al. Muscle water and glycogen recovery. PubMed.
3. Olsson K, Saltin B. Body water varies with glycogen changes. PubMed.
4. American Heart Association. How much sodium should I eat per day? heart.org.
5. White CP, et al. Fluid retention across the menstrual cycle. PMC.
6. NHS. Oedema (swelling): causes and when to see a GP. nhs.uk.
7. National Academies. Dietary Reference Intakes for Water. nap.nationalacademies.org.
8. American Heart Association. Staying hydrated, staying healthy. heart.org.
9. CDC/NIOSH. Urine color and hydration. cdc.gov.
10. American Heart Association. Potassium and sodium. heart.org.
11. National Kidney Foundation. Potassium and CKD. kidney.org.
12. AASM. Caffeine effects on sleep. jcsm.aasm.org.
13. FDA. Questions about weight loss products. fda.gov.

Educational content only; not medical advice.