Kelly Brooks, MD, is a family medicine resident at Family Medicine Milton, part of the University of Vermont Medical Center.

Kelly Brooks, MD, is a family medicine resident at Family Medicine Milton, part of the University of Vermont Medical Center.

Although it may seem like a simple thing, staying well-hydrated with water (which is considered an essential nutrient!) is becoming more and more important as we begin to understand how much it affects our health.

New research from the University of Michigan shows that not being well-hydrated is linked to obesity and being overweight (Source: Annals of Family Medicine, July 2016).

Functions of water in the body

  • Water makes up approximately 60 percent of your body weight (this varies some depending on your body composition, and whether you are male or female).
  • Water does all of these things!
    • Regulates your body temperature
    • Helps keep tissues such as the mouth, nose and eyes moist
    • Protects your vital organs
    • Lubricates joints
    • Helps the kidneys and liver flush out waste products from the body
    • Helps prevent constipation
    • Helps to dissolve nutrients and minerals so they can be used by the body
    • Helps to carry oxygen and nutrients to cells throughout the body and within every organ system
  • Lack of enough water to complete these body functions is called dehydration. Even mild dehydration can cause you to feel tired or give you other symptoms such as a headache.

Here are some tips to staying well-hydrated:

  • The amount of water or fluid an individual needs every day varies, based on things like how active you are, what other health conditions you have, and even what kind of climate you live in.
  • The Adequate Intake (AI) of water, according to the Institute of Medicine, is approximately 3.7 Liters per day for adult males, and 2.7 Liters per day for adult females.
  • Pure water does not have to be your only source of fluid; many beverages are mostly composed of water and can contribute to your daily fluid intake. Things such as coffee, tea or sodas can contribute, but certainly should not be the majority of your fluid intake. Remember that water is the best source of fluid intake because it is sugar-free, calorie-free and caffeine-free!
  • Try drinking seltzer or sparkling water instead of soda or sports drinks, which can often have a surprising amount of sugar or caffeine.
  • Try unsweetened iced tea or iced green tea for an afternoon treat (watch out for how much caffeine or sugar it may contain).
  • Try adding sliced fresh fruit (orange slices, lemon or lime slices or berries) to your water to make a delicious “fruit-infused water”
  • Be sure to drink plenty of water and have healthy snacks when it is hot and humid out to be sure to help replace the water, salts and other nutrients your body loses when you sweat!
  • Try and drink a glass of water with each meal, and between each meal.
  • Drink water before, during and after exercise.
  • You may need to increase the amount of fluid you take in based on certain health characteristics or how active you are. For example, if you are pregnant or breast-feeding, if you have an illness that causes diarrhea or vomiting, if you are very active and exercise vigorously, or if you live in a hot or humid environment. Talk with your doctor if you’re experiencing any of these things to get a better sense of the appropriate amount of water or fluids you should be taking in.
  • Keep in mind, there are certain health conditions that require you to limit the amount of water, salt or other nutrients you take in during the day. Talk with your doctor to see if this applies to you.

Kelly Brooks, MD, is a family medicine resident at Family Medicine Milton, part of the University of Vermont Medical Center. Kelly has interests in medical education and physician/student wellness, integrative medicine, women’s health, and geriatrics. Outside of medicine, she enjoys yoga, watercolor painting, drawing, and loves good ol’ New England outdoor activities such as hiking and skiing. 


Chang, T, Ravi, N, Plegue, M, Sonneville, K, Davis, M. Inadequate hydration, BMI, and obesity among U.S. adults: NHANES 2009-2012. Annals of Family Medicine, Vol 14 (4). July/August 2016.

“Water: How much should you drink every day?” Mayo Clinic: Patient Care and Health Information. Updated: Sept. 5, 2014.

Dietary and Reference Intakes Tables and Application. The National Academies of Sciences: The Institute of Medicine.

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