What You Need to Know About Staying Hydrated
Updated: May 26
Written by: Julie Tang, MS, RDN, CNSC
According to the U.S. Geological Survey, at one year of life, the human body contains 75% of water. By the time we reach adulthood, it decreases to 60%. That is still a pretty significant amount!
For the majority of our life, water makes up more than half of the body and it’s distributed throughout the different body parts. Maintaining the right amount of water in our body is important for homeostasis, which is the body's ability to maintain a relatively stable internal environment.
Our body does this by balancing our intake with output through mechanisms involving thirst, kidneys, and hormones. We lose fluids through sweating, urinating, gastrointestinal losses, and even breathing. It is vital to replenish our daily losses by taking in enough water to maintain homeostasis.
Why the water is important
These are some of the important roles water plays in our body and the reasons why proper hydration is so important:
Proper organ function
Transporting nutrients and oxygen to cells
Regulating body temperature
Flushing away bacteria
Regulating blood pressure
Ability to focus more
Improved physical performance
Reducing the risk of kidney stones
Helping with portion control and overall weight management
How much fluids do we need?
For a healthy adult, it is generally recommended to have 1 milliliter per calorie consumed or about 30 milliliters per kilogram of body weight (to convert your weight from pounds to kilograms, divide the number of pounds by 2.2). The standard fluid recommendations may seem like a lot, but keep in mind, not all fluids have to come from water.
For some people, fluid needs may be even higher if they’re physically active, breastfeeding, dehydrated, and/or during warmer temperatures. For others, they might require fewer fluids when instructed by their physician due to certain medical conditions. Overall, fluid needs and losses vary from individual to individual, so it’s best to check with your physician for a more individualized approach.
What counts as fluids?
Fluids can come from beverages such as juice, smoothies, milk, tea, and coffee, but water remains the best way to stay hydrated, without the worry of excess sugar, caffeine, or fat. In addition, foods such as fruits, vegetables, soups, broths, and yogurt can also provide some fluids.
On average, about 80% of our fluid needs come from drinking water and other beverages while the other 20% comes from foods. It is recommended to have water as your main source of hydration. Continue to monitor for signs of dehydration that include dry mouth, chapped lips, dark-colored or minimal urine output, dry skin, lack of energy, irritability, and/or dizziness.
How you can stay hydrated
1. Have a reusable, BPA-free water bottle.
Have a reusable water bottle to refill throughout the day. Consider having multiple reusable bottles and place them in a few of your most frequented spots. That way, even if you forget to pack one, you will have one ready on hand. Look for BPA-free bottles to ensure the product is safe to drink out of.
2. Include water-rich foods in your diet.
Drinking fluids is a sure way to meet hydration needs but you can also stay hydrated by eating foods that have high water content such as watermelon, cantaloupe, orange, cucumber, lettuce, zucchini, broths and soups, celery, bell pepper, tomato, lettuce, cabbage, and coconut water.
3. Freshen up your water.
Get creative and add natural flavors to your water using citrus, berries, cucumber, or herbs such as mint or basil. This could help encourage you to drink more throughout the day!
4. Hydrate when you drink alcohol.
Build the habit of drinking one to two glasses of water before you drink alcohol and in between each alcoholic drink. Alcohol has a diuretic effect that can cause you to become dehydrated and increase your chance of having that awful hangover. It’s best to have alcohol in moderation by practicing the recommendation: For women, limit to one alcoholic drink per day. For men, limit to two drinks per day (serving size of the type of alcohol consumed will vary).
5. Set an alarm or reminder.
Since most of us carry our phones with us throughout the day, consider setting a recurring reminder or using a phone app that alerts you to drink more fluids.