The big benefits of plain water

Mallika Marshall, MD

Contributing Editor

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Water, water, every where, nor any drop to drink.” Unlike Samuel Taylor Coleridge’s Ancient Mariner, who was surrounded by undrinkable salt water, most Americans have an unlimited supply of clean water to quench our thirsts.

Yet many of us turn a blind eye to it and instead reach for other beverages throughout the day, like sodas, juices, coffee, and tea, despite warnings from health experts over recent years about the added calories in sweetened beverages and the health benefits of plain water.

Now a recent study in the Journal of Human Nutrition and Dietetics provides even more evidence that we should choose water over other drinks if we want to control our weight. For the study, researchers from the University of Illinois looked at data on the eating (and drinking) habits of 18,311 adults as recorded in the National Health and Nutrition Examination Survey between 2005 and 2012.

Survey participants were asked to recall their dietary intake over two separate days. They reported their consumption of plain water (which included tap water, water from fountains and water coolers, and bottled water) as well as their consumption of other beverages like soda, fruit drinks, energy drinks, sports drinks, and sweetened bottled waters. Participants were also questioned about their intake of “energy-dense, nutrient-poor” foods, like cookies, ice cream, chips, and pastries.

On average, participants drank 4.2 cups of plain water a day and took in 2,157 calories. About 125 of those calories came from sweetened beverages, and about 432 calories came from energy-dense, nutrient-poor foods.

The researchers found that the participants who drank the most plain water in their daily diet consumed fewer total calories, drank fewer sweetened beverages, and took in less total fat, saturated fat, sugar, salt, and cholesterol. In fact, they discovered that increasing plain water consumption by one to three cups a day could decrease calorie intake by 68 to 205 calories a day. That could add up to a lot fewer calories over time — and result in significant weight loss.

These results support prior research on this topic, which has shown that drinking water before meals and that substituting water for sweetened beverages can cut down on calorie intake and improve weight control. That means people interested in losing weight and improving their overall health could benefit from incorporating more plain water into their daily diet.

So next time you’re thirsty, instead of ignoring your kitchen sink at home or the bubbler at work, take a moment to savor the one drink that’s free, refreshing, and actually good for us: plain old water.


  1. Judy lapierre

    I’m surprised nobody has spoken about Kangen water®. Best thing I ever did was start drinking ERW, electrolyzed reduced water. Not on trial anymore, lots of solid research. Pub med is full of studies reporting the great results in pretty much any oxidative or inflammatory condition! Many people and pets could very easily improve their health!

  2. Maria Jasmine Freeman

    A thirst sensation deserves to be quenched by Clark water and the balanced electrolytes contained. No sugar or salt, or any additive is demanded by our body, so why take other than water. Taking other- than -water -drinks promotes pathogenic gut bacterial overgrowth due to refined sugar availability, depriving otherwise healthy bacteria of their nutrients-fiber, gives nutrient-lacking calories, and curbs intake of healthy food by suppression of appetite.
    Moreover, children on soft drinks grow more stubby than those on milk intake, while those on Caffeine-containing supplements turn, in addition, with a lower bone mass density!
    Man, 75-85% percent water, was made to drink water and not otherwise; it is depressing how ads spread the word about other -than -water drinks, and succeed at it!

  3. Janet

    I have an under the sink water filter which is serviced by a company, although I imagine it can be done by a DYI er. I use a twist of LIME in water with ice and it is the best thing…no chemicals, no caffeine, no calories, and a little vitamin C to boot. Tastes great. Not a fan of lemon. I wish I discovered this years ago. I will never drink soda or juice again.

  4. Lokesh Punj

    The best I have tried myself after relieving myself — is to gulp about 2 litres of water at room temperature as the first thing in the morning and go for morning walk / read news paper and eat biscuits or take morning tea, etc. only after 45 minutes of that..It keeps all systems quite toned up and helps metabolism.
    Initially, it is difficult to drink 2 litres but one can drink as much as possible and slowly increase it to 2 litres as a ritual.

    One more descipline recommendable is to drink water at room temperature only after 30 minutes of meals…not to take cold water or cold drinks with meals…try it out for few days to note the difference..

  5. Dr. Mallika

    Thank you everyone for your insightful comments. Clearly this topic has touched a nerve with some of you. Food (or drink) for thought!

  6. V.C.Vijayaraghavan

    Governments must force restaurants and pubs to provide tap water to anyone on demand. In 99% of the cases, the answer is ‘no we don’t provide tap water, you buy bottled water from us’ which is usually costlier than wine. In England, there is a 14th century law which states any inn should provide drinking water to customers, free of charge. While That law is still operational, most restaurants flout it

  7. Almis Peter Salcius

    After Flint Michigan’s real hazards, and the fluoride flake brigade campaign, I am not surprised to see the renewed hysteria regarding our precious bodily fluids. Our municipal water supplies are still the best in the world, but they are being compromised by public poverty, neglect, and the chemical hazards of fracking and other new hazards that the world did not have to deal with before. Their fears are real, even if only intuitive and not well formed into an arguable policy. People need to be educated about water and how to protect it before it’s compromised. My favorite author on the subject so far is Felix Franks.

  8. Chad

    Wish more was being done to remove fluoride from tap water.
    If somebody wants fluoride get it from toothpaste or rinses.
    A study showed some fluoride is contaminated with multiple chemicals since it is a byproduct of some manufacturing processes or is imported from China.
    If you poor a huge bag of fluoride in the river you can be arrested yet it is poured into our water!

  9. Letitia

    THE WATER FROM THE FACET IT IS NOT HEALTHY!!!!!!!!!!!!!!!!!!!!!!!!

  10. Russell Byers

    The article makes the case that drinking plain water involves the consumption of less energy than many other, particularly sugar-intense drinks and foods. I don’t believe however that it provides any reason for me to desist drinking unsweetened and unmilked tea (both black and green).

  11. Anda Friedman

    It has been already proved by Harvard scientists that water fluoridation is harmful. If it is good for somebody it should be given as medicine. For others it is not informed consent. Why Harvard does not work on eliminating it from our public water supply?

  12. Dr Anisetti Thammayya

    Very important information on the benefits of drinking water instead of beverages. we have to realize that human body with its millions of cells need water not beverages containing so many additives which are some times lead to maladies and diseases. Adequate water intake is one of the essentials for healthy life.

  13. Erin Marie

    But what about the chlorine, pesticide, pharmaceuticals, fluoride, lead, Mercury, hormones and many other contaminants in tap water. Water is good for you, be be sure to consume good quality!

  14. Flavia(Montevideo-Uruguay)

    Excelente informe,muchas gracias por compartir y difundirlo.
    Lo he comprobado hace varios años conmigo misma y el agua pura es lo más sano que tenemos disponible para beber diariamente.

  15. Mary Coakley

    I guess I am lucky I cannot exist without at least two litres a day this was checked out by my Doctor as he taught I was drinking too much but agreed for me to continue.Water I find is so refreshing and cools your thirst over all the minerals.

  16. Jonathan Jan

    Water is the most complicated substance on this planet. Life began when double-helical small cluster water was formed as result of holographic projection by cosmic radiation. This is the substrate for DNA architecture. Water fortified with colloidal trace minerals can deliver catalysts to the cell membrane and mitochondria for intra-cellular energy conversions. High-density small cluster water (structured water) is more advanced memory device than DRAM.

  17. Lee Coppack

    Coffee and tea get thrown in with sweetened drinks at the start but then the article doesn’t mention them further. If highly sugared, sure, but what’s the disadvantage of plain black or with a little milk? Or herbal tea. And as Nikki Zang says, there is likely to be an element of confirmation bias here.

  18. Jackie

    Great idea if you are sure your water doesn’t contain mercury lead etc.
    how does one find out if their water at home or in the office is pure and safe?

    • Susan

      Hi, Jackie. I don’t know where you live, but in El Dorado County, California, there is a water analysis published annually, showing minerals, coliform and other bacteria content, etc. Call your local state or county health department.

  19. Nikki Zang

    This is interesting but couldn’t it also be that people interested in healthy living already drink lots of water and consume less junk food?

    • Jean Childers

      Nikki Zang, I was thinking the same thing. Water drinkers may have chosen water as a drink as well as determining not to consume unhealthy “energy” bars and oversugared food. No reason to suppose that water drinking creates an appetitite for quality nutricious food.

  20. mounir

    can I put your article on my facebook
    Mounir Joudeh CPA

  21. Brian Moore, MD

    One can get oneself to drink more water by adding a hint of flavor to the water: a touch of grapefruit juice, a squirt of lemon, etc.

    • Nikki Zang

      Or you could make unsweetened herbal iced or hot tea. There is nothing superior about plain water to water that had been flavored with peppermint or lemongrass.

      • jonathan jan

        Small cluster water (structured water) fortified with colloidal trace minerals can deliver intra-cellular catalysts for energy conversion at the cell membrane and mitochondria. Herbal teas have both organic aromatic flavonoids and inorganic minerals.

  22. Cathy Broun

    Please comment on alkalyzed or ionic water…a food-sharing place here in Cincinnati has been offering this to their participants…

    • Jonathan Jan

      pH value is a poor indicator of acidity. There are many non-chemical ways to change the H-O-H bond angle and give high pH reading while the water is neutral. H2O does not exist as a single molecule.

      • Sheila Barnett

        Re deionised water : I have drops containing:

        Deionised water, potassium bicarbonate, potassium citrate, potassium lactate, TriPotassium phosphate, calcium, selenium, magnesium, zinc and ‘Aminozone’ ( a brand from Better Health Lab which contains 78 amino and chelated trace minerals including calcium, zinc, manganese,and silver from ‘ancient marine deposits’)

        Would these drops, in your opinion, be effective as an ‘Alkaline booster with antioxidant’ as the makers claim?

        ( I have interstitial cystitis and reducing acidity is important in controlling pain )

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