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By suppressing stress hormones and turning up the heat on fat metabolism, water can absolutely promote weight loss.
Of course, unlike the fifteen radio ads for “super fat burner 3000” pelting your ears on every commute, you won’t hear any arguments for plain old water as a weight loss tool.
And yet, water has been consistently proven in research to boost metabolism safely and sustainably in a demographically diverse range of study participants.
Obviously, anyone who has ever been thirsty is aware of water’s role in survival, but it’s time we gave it more credit for the additional benefits it can provide as a weight loss tool, stress reducer, and even a skin care product.
Here’s what the research says about water, weight loss, and some of those other helpful benefits.
As always, the record is always being revisited and remodeled, but as it stands currently, scientists are mainly pointing to two mechanisms water uses to keep the pounds off: suppression of a stress hormone and enhancement of fat metabolism at the cellular level.
Though our overstressed and overworked bodies need no introduction to angiotensin, the conscious mind does, so we’ll start there.
Angiotensin II (AngII) is a hormone released by the body when it is under certain forms of stress, like physical exercise or, in this case, dehydration.
In addition to angiotensin’s several effects on the kidneys, heart, and blood vessels is the promotion of fat creation (lipogenesis) and simultaneous suppression of fat metabolism (lipolysis).
Like most hormones we unknowingly abuse, AngII has many important, protective benefits in the short term, but chronic exposure leads to a lot of problems.
This study by the Universite de Lorraine in Vandoeuvre les Nancy, France found that “chronically elevated AngII appears to be involved in several chronic human diseases…antagonists of the renin-angiotensin system are prescribed in 85% of cases to treat cardiovascular disease.”
In other words, we’re leaving the angiotensin fountain on for far too long by stressing our bodies out with dehydration, poor nutrition, and lifestyle choices, thereby impairing our metabolism (and messing with our blood vessels) enough to promote diabetes and heart disease.
Since thirst is the primary trigger for angiotensin release, this study and others concluded that maintaining proper hydration will cut down on angiotensin, which will in turn crank our natural fat metabolism back up.
TL;DR: Drink more water to keep fat-promoting stress hormone angiotensin II at a healthier level.
Echoed universally enough to become a meme, that quintessential line we’ve all heard in biology class—“The mitochondria is the powerhouse of the cell”—comes into play here.
When the body is adequately hydrated, the cells are adequately hydrated, which scientists can detect fairly accurately by measuring their (increased) volume.
In many cases, a properly hydrated cell means the important organelles within it (e.g., the mitochondria and others) can function with greater efficiency.
Since the mitochondria is responsible for generating the energy required for a large range of reactions, many of them falling under metabolism, this means that it can promote fat metabolism more potently when it is boosted by adequate hydration.
This increase in metabolism caused by hydration is also referred to as “water-induced thermogenesis” (because nothing else sounded as cool), and it has held up under experimental conditions.
As concluded by this study from Dr. D.Y. Patil Medical College and Hospital in Navi Mumbai, India that measured the effect of increased hydration (1500 milliliters a day for all 50 overweight participants) on body weight, body composition, and body mass index (BMI), water-induced thermogenesis is indeed a thing.
All three metrics for body mass declined among participants, and obviously, the water was well-tolerated by all.
Since hydration has so many benefits beyond weight management, we’re going to go through a “lightning round” of sorts, rattling off several of the most important boosts it can provide for mind and body.
Drinking water can reduce your stress levels by suppressing cortisol, a stress hormone somewhat similar to angiotensin that will also add some pounds to your midsection.
Water is an important constituent (the base, really) for the fluid that cushions our joints, meaning adequate hydration is key to naturally staving off joint pain.
Staying hydrated is crucial to keeping wrinkles at bay, as water adds to your skin’s elasticity (and also makes scars and aging spots less visible).
Blood is more than 80% water, so yeah—we need blood.
Water also helps to flush out toxins, both by helping the kidneys do their job better and through several other mechanisms.
With the help of key electrolytes and hormones, water can help to regulate blood pressure.
Staying hydrated can prevent injury and improve performance when exercising.
“But wait, there’s more.”
No really, there are at least several dozen more benefits to staying hydrated, but you get the idea.
With all this praise, you’d think hydration is one of those “can’t have too much” situations, but it actually isn’t.
Tragically, people have died from consuming too much water, including distance runners overdoing the water stations and participants trying to win a car in poorly planned contests.
In the majority of cases, the cause of death by overhydration is hyponatremia, which refers to a severe lack of sodium in the blood (“Na” for sodium on the periodic table, “hypo-” for low, “-emia” for blood.)
Put simply, when the body is majorly overhydrated, it dilutes the sodium content in our blood to potentially lethal lows.
Other than the fact that you just chugged two gallons or more of water, one way to detect this issue and potentially save a life is to watch for signs of disorientation and/or “fogginess.”
The idea is not to fixate on some catch-all RDA (recommended daily allowance), because even the CDC claims there is “no recommendation for how much plain water adults and youths should drink daily.”
Instead, consider your re-commitment to hydration an exercise in listening to your own body.
If you feel cranky, foggy, tired, and stressed, remember that water can help, and keep in mind how quickly these problems go away after having a cup.
Of course it helps to regularly have water around mealtime, but many of us are lacking in the in-between as we focus on our daily lives.
It sounds weird, but you can even replace a nervous tic (chewing gum, tapping your feet, etc.) with drinking water to help the habit become automatic that much faster.
Whatever you have to do, do it, forget about it, and save the forehead palm for a couple weeks down the road when you’re feeling and looking much better.
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