If you’ve ever noticed that the number on the scale fluctuates by a few pounds each day, know it’s completely normal. It’s likely just due to water weight gain or loss.
What is water weight, exactly? Well, “water has a weight to it,” explains Leslie Bonci, M.P.H., R.D., author of Sports Nutrition for Coaches, and founder of Active Eating Advice, based in Pittsburgh, Pennsylvania. “In fact, 16 ounces of water weighs one pound, so if you drank 32 ounces of water and weighed yourself before drinking it and after, guess what? You might be two pounds heavier.” And if you miss a meal or don’t drink much water one day, that loss of water weight might also mean you weigh a few pounds less than the day before.
While it’s fine for weight to move up and down slightly in short periods of time, water weight can also be a cause for concern in some cases. Here’s what to know about what causes water weight, when to talk to a doctor about it, and how to lose it in a healthy way.
What is water weight and what causes it to increase or decrease?
Water weight, technically speaking, is the retention of fluid that can cause you to gain weight. As mentioned, you can gain water weight by simply consuming lots of water or on the other hand, not drinking enough. That sounds counterintuitive, but this triggers your body to hold onto as much water as possible so it can properly function. But that’s not all that can cause weight gain from water.
“It can be caused by many things, such as a high-sodium diet, changes in your menstrual cycle, heart failure, or it can be an adverse reaction to medication,” explains Alicia Shelly, M.D., expert at HealthTestingCenters.com.
Regularly taking NSAIDs, like ibuprofen, can also contribute to fluid retention, explains Bonci.
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What does water weight feel like?
While every person is different, water weight tends to manifest in the body in a few common ways, Bonci says, including:
- Bloating, especially in the abdominal area
- Swollen legs, feet, and ankles
- Puffiness of the abdomen, face, and hips
- Stiff joints
- Weight fluctuations
- Indentations in the skin, like what you see on your fingers when you’ve been in the bath or shower a long time
“Typically, water weight will be felt in the gut, and sometimes in the limbs or face,” says Bonci. “You might feel bloated or like you’re more swollen than normal.” While this water weight is normal, if you’re feeling extremely bloated or more puffy than normal and it isn’t going away on its own, consider reaching out to your primary healthcare physician or medical professional.
What health concerns are associated with water weight?
While the bloating or puffiness that comes from water retention might not feel comfortable, it’s generally fine for your health. Many females will experience water weight gain during their menstrual cycle, which is common and not a cause for concern, and it should improve on its own, explains Dr. Shelly.
There are a few times, though, when water weight can be an issue. “It would be concerning if the water weight does not subside,” explains Bonci. “Also if a person is seriously over-consuming water, which could lead to hyponatremia, or low sodium levels, which could result in fluid in the lungs or brain, and is potentially fatal. That is why fluid needs are not unlimited and it is possible to consume too much.”
Water weight can also be alarming when it’s related to heart failure. “It can indicate that too much water is being retained,” explains Dr. Shelly. Other signs of heart failure include feeling congested in your lungs, dizziness, fatigue, weakness, and irregular heartbeats, so if you’re experiencing any or all of these symptoms, seek medical attention right away.
Keep in mind, you don’t need to weigh yourself excessively or obsess over a few pounds caused by water retention. If you’re a healthy individual who consumes H2O regularly, then there’s no concern and the pounds will just come and go. But if you see the scale number change drastically or you have other reasons to be concerned about your health, there are a few things to look for to determine if you should see a professional.
For example, you notice pitting edema (when you push your finger into a swollen area of your body and it creates a dimple or a “pit” after a few seconds), that is a cause for concern and a reason to contact your primary care physician, explains Bonci. Also contact your physician or a medical professional if you’re experiencing a persistent headache, excessive swelling, shortness of breath, or anything out of the ordinary that accompanies those typical signs of water weight, Bonci says.
How do you lose water weight?
You won’t ever be able to completely get rid of water weight—and you shouldn’t. “Water makes up 60 percent of total body weight, so having less than that is not advised,” explains Bonci.
However, Dr. Shelly says there are some things you can do to help decrease excessive weight gain caused by fluid retention:
- Decrease sodium intake: Most American adults tend to consume too much sodium, so be sure to stick to the USDA Dietary Guidelines, which says to limit your sodium intake to less than 2,300 milligrams per day.
- Increase water intake (but don’t have too much): Drink up, aiming for about 125 ounces (or about 15 and a half cups) for men and approximately 91 ounces (about 11 cups) of water each day for women. (Read more about how to make sure you’re drinking enough water.)
- Exercise: Lucky for runners, exercise can help you de-bloat by stimulating blood flow and circulation, which reduces fluid build-up in legs and feet. Plus, exercise creates sweat, which is also fluid loss.
Should runners be concerned about water weight?
Not so much. Generally speaking, it’s not a bad thing for your weight to fluctuate due to water weight gain or loss—the weight and side effects from it can disappear as quickly as they come. But if you notice abnormal changes with your body, like serious swelling in your ankles and a big increase in weight after a long run, then call your doctor or a medical professional.
Most importantly when it comes to monitoring your weight: “Don't obsess with the scale and don't drink to excess,” says Bonci. The best thing you can do is accept the fluctuations in your body and take good care of yourself so you simply feel good.
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Amy Schlinger, NASM-CPT
Amy Schlinger is a health and fitness writer and editor based in New York City whose work has appeared in Men’s Health, Women’s Health, The New York Post, Self, Shape, Cosmopolitan, Glamour, and more; The National Academy for Sports Medicine Certified Personal Trainer (NASM-CPT) is extremely passionate about healthy living and can often be found strength training at the gym when she isn’t interviewing trainers, doctors, medical professionals, nutritionists, or pro athletes for stories.
