How many ounces of water should you drink per day?
Water is essential to life — and your health. Understand how much you really need.
You already know you can't survive without it. But how much water should you actually drink every day? You may have heard of the "eight glasses a day" rule. While this might be right for some, the truth is there's no one-size-fits-all answer. Staying hydrated starts with knowing your body's specific needs.
How hydration impacts your health
Everybody (and every body) needs water to work properly. Some of the ways it keeps you healthy:
- Eliminating waste through urine, bowel movements and sweat
- Keeping joints healthy and lubricated
- Regulating body temperature
- Aiding with bladder and kidney function
- Improving digestion
- Protecting sensitive tissues
- Keeping skin from drying out
The benefits of increasing your water intake
Some people set a goal to drink a gallon every day. Drinking plenty of water has its advantages. Among them:
- Reduced hunger
- Increased energy
- Smoother, healthier skin
- Balanced body fluids for circulation and digestion
- Improved brain power
- Enhanced agility and body movement
But while there are benefits to guzzling a gallon (128 ounces) of water each day, it’s not a requirement for everyone.
How many ounces of water should the average person drink?
The key to proper hydration: paying attention to your body and learning what it needs.
On average, a healthy adult should take in the following amounts of water per day:
- 125 ounces (15.5 cups or 3.7 liters) for men
- 91 ounces (11.5 cups or 2.7 liters) for women
However, your daily needs can vary based on other factors. You may need to adjust your fluid intake to account for:
- Weather: When it's hot, hydrate more. Warm temperatures can make you sweat, making you lose fluids faster. Higher altitudes can cause dehydration, too.
- Exercise: You lose fluids when you're sweating from being physically active. Drink lots of water before, during and after you exercise.
- Sickness: Fever, vomiting and diarrhea can cause dehydration. Replenish with plenty of fluids or follow your doctor's recommendations for rehydration.
- Pregnancy: If you're pregnant or breastfeeding, drink extra water. Your body is producing fluids for two.
About 20% of your daily fluid intake will usually come from food, and the rest you get from drinks. If counting how many ounces you're drinking sounds like a chore, don't sweat it. You can start with just listening to your body and drinking when you feel thirsty. Keep a bottle handy so you can quench your thirst throughout the day.
How to tell if you're dehydrated
When dehydrated, your body lacks the fluids needed to carry out normal functions. You might need more water if you notice the following signs of dehydration:
- Lightheadedness or dizzy feeling
- Dry mouth and tongue and cracked lips
- Less frequent need to urinate
- Muscle cramps
- Thirst
- Frequent headaches
- Fatigue or drowsiness
- Urine has a darker color
- Eyes more sunken than usual
You can also try the skin test. Pinch one of your knuckles and let go. If you’re dehydrated, the skin will stay raised for a few seconds. If it quickly returns to normal, you’re probably okay.
“While the skin test is useful, it may not be ideal for older people,” says Alex Germano, MD, a Geisinger family medicine physician. “They often have less elastic skin that doesn’t bounce back as easily, but that doesn’t mean they’re dehydrated.”
If you notice any of these signs, the first thing you should do is drink more water.
“If you feel sick and dehydrated, talk to your doctor or pharmacist,” says Dr. Germano. “They can recommend hydration mixes that will restore minerals your body has lost.”
How to stay hydrated
Even when you know water is crucial, new habits don't come easy. Try these easy tips to up your daily water intake:
- Drinking a glass when you wake up
- Eating fruits and vegetables with high water content (e.g., watermelon, strawberries, cantaloupe, celery and tomatoes)
- Carrying a refillable water bottle and drinking from it throughout the day
- Drinking a glass with every meal
- Flavoring water with lemon or a flavor packet
- Using a tracking app or setting reminders on your phone
Once you know how many ounces of water to aim for, find what works best for your personal lifestyle. For some, taking small, frequent sips to consume water gradually throughout the day is helpful. For others, gulping large amounts at scheduled intervals is a more effective habit. There’s no wrong way to hydrate.
Can you hydrate with other beverages besides water?
"All beverages you drink, including coffee, tea, milk and soda, have a high water content and count toward your intake,” says Dr. Germano. "But go easy on soda and other sweet drinks because they’re filled with sugar and can lead to obesity, diabetes and heart disease. And be careful with the amount of caffeinated beverages you drink, as caffeine causes you to urinate more and use water faster.”
Drink to your health
Most likely, your normal eating and drinking patterns already keep you hydrated throughout the day. As you estimate how many ounces to drink daily, consider your lifestyle, the weather and your health needs. Let your thirst guide you. Water benefits almost every part of your body, so drink up!
Next steps:
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