If you check your body weight on a regular basis, you will likely notice that some days, your weight seems to fluctuate up or down rather significantly from one day to the next.
Although when we seemingly gain weight overnight, it can cause a lot of anxiety and worry that we are rapidly gaining weight, however, in most cases, it is virtually impossible to gain an appreciable amount of body fat overnight.
Sudden changes in weight are almost always attributable to changes in your body water balance and your water weight rather than actual gains or losses of fat (adipose) tissue.
But how much of your weight is water? How much water weight can you lose in a day? How do you know when you’re losing water weight vs fat loss?
In this article, we will discuss water weight gain, losing water weight, how much of your weight is water, and how to differentiate water weight vs fat loss.
We will cover:
- What Is Water Weight?
- Causes of Excess Water Weight
- How Much Water Weight Can You Lose In A Day?
- How to Lose Water Weight
Let’s jump in!

What Is Water Weight?
When people use the term “water weight,“ they can be referring to different things, ranging from how much water weight is actually in the body to a feeling of edema, or swelling due to retention of excess water, artificially increasing body weight.
In general, water comprises about 50-60% of an adult’s total body weight. Research suggests that the percentage of body weight that is water tends to be lower in women (52-55%) than men (closer to 60%), as well as lower in the elderly and obese individuals.
When the body holds onto extra water beyond these expected levels, this excess body weight due to water retention is termed “water weight.”
Water weight, or excess water retention, can cause bloating and puffiness, particularly in the abdomen, thighs, and arms.

Causes of Excess Water Weight
There are several diet, lifestyle, and health conditions that can contribute to retaining excess water and gaining water weight.
Some of the top causes of water weight gain include the following:
- Eating a high-sodium meal or following a chronic high-sodium diet
- Physical inactivity
- High carbohydrate intake and/or carb loading
- Taking certain medications such as oral contraceptives, steroids, and certain anti-inflammatory medications
- Menstruation, pregnancy, or premenstrual syndrome
- Hormonal imbalances
- Stress
- Insufficient sleep
Note that prolonged water retention, in which it is very difficult to lose water weight, can be symptomatic of kidney or liver disease or congestive heart failure, but these conditions are much rarer, and most people are able to lose excess water weight by modifying their diet and lifestyle habits.

How Much Water Weight Can You Lose In A Day?
Studies suggest that changes in the water levels in your body can cause body weight fluctuations of approximately 2 to 4 pounds in a single day, meaning that from one day to the next, your weight on the scale may change as much as four pounds simply due to differences in the amount of water your body is holding onto.
Your excess water weight may be even higher if you eat a particularly salty meal or have a larger body size.
The good news is that water retention is usually temporary, and simple lifestyle changes can help you lose water weight quickly.
It’s important to note that losing water weight is not the same as losing actual body fat.
To lose stored body fat, you need to generate a caloric deficit that burns excess stored calories. For every 3500 calories you are able to burn over that which you consume, you can lose one pound of stored body fat.
In contrast, losing water weight does not require a caloric deficit. Your body fat percentage will not change appreciably by losing water weight.
Rather, you can lose water weight by tweaking the water balance in your body and encouraging a diuretic effect, meaning the excretion of excess body water.

How to Lose Water Weight
There are several different ways in which you can naturally and rather quickly lose water weight. Here are a few techniques and tips to help you lose excess water weight:
#1: Reduce Your Sodium Intake
The number one thing you can do to lose water weight is to decrease your salt intake.
Consuming too much salt, whether habitual or in a single meal or snack, causes the body to hold on to extra water, increasing your water weight and causing bloating and puffiness.
This is because the body has to maintain a specific sodium-to-water ratio or balance, so if your body’s sodium level increases, your body has to retain more water to offset the increase.
We often assume most of the dietary salt consumption comes from salting our food before we eat it, but up to 75% of dietary sodium intake is usually attributable to sodium found in processed foods. Foods such as frozen pizza, deli meats, condiments, pickles, peanut butter, cereals, soups, cheese, pretzels, chips, and biscuits are particularly high in added salt.
According to the Dietary Guidelines for Americans, adults should consume no more than 2,300 milligrams (mg) of sodium per day, but under 1,500mg is recommended.

#2: Reduce Your Carbohydrate Intake
Eating a lot of carbs can lead to excess water weight because your body retains about four grams of water for every gram of glycogen you store.
Therefore, if you want to quickly drop some water weight, you can follow a low-carbohydrate diet and burn through your glycogen stores via high-intensity exercise, which will encourage your body to get rid of extra water weight.
#3: Cut Out Alcohol
Alcohol is technically dehydrating, but the body can overcompensate for this effect by holding onto water as if it’s a limited resource.
Additionally, alcohol is metabolized before carbohydrates, fat, and protein, so it can affect your digestion and metabolism, all of which can cause you to hold on to extra water weight.
#4: Drink More Water
Although it seems counterintuitive, drinking more water can help you lose water weight. The body actually retains more water when water seems scarce—as when you are dehydrated.

#5: Try a Natural Diuretic
Certain foods and drinks may contain compounds that encourage the body to excrete excess water.
For example, green tea and black tea can be natural diuretics because they contain caffeine. Studies also suggest that foods and herbs like dandelion, coriander, fennel, radish, and melon have been shown to reduce water retention.
#6: Get More Sleep
It may sound surprising, but a lack of sleep has actually been shown to increase water retention, potentially causing an uptick in your water weight gain.
Although the exact mechanisms are not fully understood, it is thought that a disruption in the body’s circadian rhythm caused by insufficient sleep can alter the production and secretion of the hormone vasopressin.
Vasopressin is considered an antidiuretic hormone, meaning that higher levels lead to excess water retention.

#7: Work Out
Getting in a good workout is certainly an effective way to quickly drop some water weight because the body loses water through sweat.
However, it’s important to note that you really should rehydrate after your workouts, potentially counteracting the temporary decrease in body weight–and water weight–you experience.
With that said, because you’ll also lose sodium through sweat, even if you rehydrate after exercise, as long as it’s plain water, you can still improve your overall sodium/fluid balance, which may decrease your water weight.
#8: Boost Your Potassium Intake
Eating food high in potassium, such as bananas, avocados, mushrooms, beet greens and other greens, potatoes, Lima beans, dairy products like yogurt, citrus fruits like oranges and grapefruits, honeydew, cantaloupe, watermelon, and honeydew can potentially help you drop excess water weight.

Potassium is an electrolyte that kind of works in opposition to sodium, such that increasing your potassium intake can help the body excrete excess sodium.
Since sodium increases water retention, decreasing your sodium levels by boosting your potassium intake can help shed excess water weight.
Overall, water weight can contribute several pounds to your reported body weight on the scale and can lead to feelings of bloating and puffiness.
Cutting back on sodium, alcohol, and carbohydrates may help you lose several pounds of water weight.
If you’re concerned about chronic water retention, speak with your doctor about potential underlying health conditions and potential medications to help you manage your body water and decrease water weight retention.
To ensure you stay well-hydrated, especially if you work out, check out our hydration guide for tips and tricks.
