How much water to drink to lose weight in 3 days

When you think weight loss, your mind probably goes to a few places: more exercise, healthy food, plenty of sleep, stress reduction. Drinking more water may not be on the list—but it should be! (Plus, who doesn't love the look of a super cute water bottle?) This begs the Q: How much water should I drink to lose weight?

Table of Contents Show

Can drinking water help you lose weight?
Can you gain weight from drinking too much water?
For the average person:
If you're working out a lot:
If you're more overweight:

Drinking water is important for many reasons. "Drinking water helps regulate body temperature, keep our joints lubricated, prevents infections, deliver nutrients to cells, and keeps our organs and body functioning properly," says Seattle-based registered dietitian nutritionist Angel Planells, RDN, who is a national media spokesperson for the Academy of Nutrition and Dietetics. And, did you know? Water makes up about 50 to 70 percent of your body weight, according to the Mayo Clinic.

There is no question that water is essential to survival. If you're trying to lose weight, drinking water also plays a huge part in whether you can achieve your goals.

Can drinking water help you lose weight?

The short answer is yes, and its benefits are backed up by science:

Water is a natural appetite suppressant. A 2018 study published in Clinical Nutrition Research found that people who drank 300 mL of water before a meal ate less than those who didn't consume any beforehand.
It helps torch fat. Water actually plays a critical role in the process your body uses to burn fat (a.k.a. lipolysis). A 2016 mini-review of animal studies in the journal Frontiers in Nutrition found that increased water intake can result in loss of body fat by reducing food intake.
It can burn calories. One 2007 study found that people who drank 500 mL of water reported greater resting energy expenditure by 24 percent just 60 minutes after hydrating.
It can promote long-term weight loss. A 2013 review of 11 studies on water's impact on weight found that people who upped their water consumption along with adopting a weight loss plan reported dropping more pounds three to 12 months later than those on a weight loss plan alone.

This is where things get a little tricky, so let's start with a baseline: Drinking 64 ounces of fluid a day is the rule of thumb to keep your system operating at peak efficiency, according to the Cleveland Clinic. On a daily basis, the National Academy of Medicine recommends that women get 2.7 liters (about 91 ounces) of water per day.

But the amount of water you should be drinking to lose weight may be different from how much someone else should be having, according to Planells. For example, if you work out regularly, you will naturally need more water than those who don't. The same is true for women who are breastfeeding vs. those who aren't. So there isn't a one-size-fits-all answer to how much you should be drinking. But at a minimum, it should be 64 ounces. That's eight cups of water every day.

Drinking at least 64 ounces (eight cups) of water every day may help with weight loss.

Downing liquid is not the only way to meet this goal. About 20 percent of your hydration needs can be met through your diet, says Caroline Susie, RDN, a national spokesperson for the Academy of Nutrition and Dietetics. For example, foods with 90 to 100 percent water content include fruits, especially cantaloupe, strawberries, and watermelon and veggies like lettuce, cabbage, celery, spinach, and cooked squash.

Foods that contain 70 to 89 percent of water include fruits like bananas, grapes, oranges, pears, and pineapples; vegetables such as carrots, cooked broccoli, and avocados, and dairy products like yogurt, cottage cheese, and ricotta cheese. Incorporating these water-rich foods as much as possible can help ensure you're hitting your goals.

Can you gain weight from drinking too much water?

However, drinking too much water can make you put on weight, which is known as water weight. One major contributor to water weight is your salt intake. Having too much salt may cause water retention, says Planells.

If you're looking to shed excess water weight, here are a few strategies.

Stay hydrated. "Being in a dehydrated state can make your body hold onto to extra water," says Planells. So while you may think you can get rid of water weight by not drinking, it's actually the opposite.
Get moving. Being physically active can help since it makes you sweat. "As your heart rate goes up, you will circulate blood flow around the body and reduce fluid buildup in your legs and feet," says Planells. Note that you will need to replenish some of the fluids lost during your workout.
Cut back on carbs. When you eat too much carbs but your body doesn't use all of them, they are converted into glycogen, which is stored in your muscles with water.

Drinking too much water could also lead to a condition called hyponatremia, which occurs when the sodium level in your body is below normal, and it can be life-threatening because sodium is needed to maintain fluid balance, blood pressure control, and nerve and muscle regulation. When the sodium level in your blood is too low, extra water goes into your cells and makes them swell, per the National Kidney Foundation.

If you're concerned that you aren't drinking enough (or are consuming too much) water, you should check in with a registered dietitian or physician who is working with you on your weight loss goals. They can make sure you are properly hydrating, and choosing the best beverages for your health.

Losing weight requires a consistent commitment to several lifestyle choices: Eat healthier, exercise more, get 6-8 hours of sleep a night, and drink lots of water. Not only will choosing water over caloric and sugary beverages save you calories, but water is also essential for sharp brain function, keeping your organs working properly, and exercise recovery — to name a few important reasons. And if you're reaching for detox water, it can help boost your metabolism and flush out toxins.

But just hearing that you need to drink "lots" of water can be confusing. For some people that could be the standard eight 8-ounce glasses, but others could need a lot more (or perhaps less). We tapped dietitian Jim White, RD, ACSM, and owner of Jim White Fitness and Nutrition Studios, to find out just exactly how much water you should be drinking for weight loss. And while you're making some changes, be sure to try out any of these 21 Best Healthy Cooking Hacks of All Time.

For the average person:

Although everyone has different needs, White says sticking to the oft-recommended amount of eight 8-ounce glasses (64 ounces total) should suffice and can help boost weight loss for the average person or someone just looking to drop a few pounds.

It doesn't sound like an overwhelming number, but the challenge for most people is drinking enough water in the first place. According to a study by the CDC, 43% of adults drink less than four cups of water a day, with 7% reporting they don't drink any glasses of water—yikes!

In general, you should let your thirst be your guide. If you're still thirsty after chugging 64 ounces throughout the day, make sure you adjust your intake accordingly. But if you're feeling quenched, be sure not to overdo it; drinking too much water could lead to hyponatremia, also known as water intoxication, where the sodium levels in the body become overly diluted and can lead to swelling in the brain, seizures, and coma. There's a reason this dangerous practice is one of the ways you're drinking water wrong.6254a4d1642c605c54bf1cab17d50f1e

If you're working out a lot:

If you're a big-time gym rat or endurance athlete, you'll need more water than the standard 64 ounces. After a serious sweat sesh, you could be depleting your body of proper hydration.

"The American College of Sports Medicine recommends to drink 16 ounces of extra water before you exercise, and to sip on 4-8 ounces during exercise, and another 16 ounces after exercise," White explains. "You can also weigh yourself before exercise and see how many pounds you lose. Drink 16 ounces afterward for every pound lost."

RELATED: Your guide to the anti-inflammatory diet that heals your gut, slows the signs of aging, and helps you lose weight.

If you're more overweight:

For overweight or obese people, their water needs are different. White says they'll need to drink even more water to stay properly hydrated and aid in weight loss. A simple math equation for this is to drink half of your body weight in ounces of water. So if you weigh 180 pounds, you should aim for 90 ounces of water a day.

A study published in the Annals of Family Medicine found that people with higher BMIs were the least hydrated. The study suggested that water is an essential nutrient and may play as big of a role in weight loss as food and exercise. Virginia Tech researchers found that overweight adults who drank 16 ounces of water a half an hour before their meals lost three more pounds than those who didn't, and 9 pounds at the end of 12 weeks.

Replacing caloric and sugary beverages such as soda, fruit juice, and sweetened iced teas with water can also help boost weight loss, White says.

Although everyone has their own individual hydration needs, shooting for 64 ounces is a good place to start. Let your thirst be your guide; if you're still parched after 8 glasses, feel free to drink more (just don't go overboard).

Another indicator for if you've had enough water is the color of your urine: A pale yellow or almost clear color means you are properly hydrated. Anything darker than a pale yellow, and you need to drink more H2O.

"Remember the signs of dehydration: Thirst, dry mouth, headaches, and in extreme cases dizziness and feeling lethargic," White explains. "Just a 2% dehydration in the body can negatively impact athletic performance."

There are other factors that could impact just how much water you should be drinking: Sweating more, being outside in the heat, taking certain medications, or drinking alcohol. White recommends to drink one 8-ounce glass of water for every alcoholic beverage you consume, and get plenty of hydrating foods such as watermelon, cucumbers, and celery.

Regardless, a weight-loss program should include around 64 ounces of water — more if you've got a lot of weight to lose or your program involves a lot of working out. So grab a reusable, BPA-free water bottle, keep refilling it, and sip your way slim.