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What would happen if you didn’t drink water? - Mia Nacamulli

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    Water is virtually eveywhere,
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    from soil moisture and ice caps,
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    to the cells inside our own bodies.
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    Depending on factors like location,
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    fat index,
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    age,
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    and sex,
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    the average human is between 55-60% water.
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    At birth, human babies are even wetter.
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    Being 75% water,
    they are swimmingly similar to fish.
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    But their water composition drops to 65%
    by their first birthday.
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    So what role does water
    play in our bodies,
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    and how much do we actually need to drink
    to stay healthy?
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    The H20 in our bodies works to cushion
    and lubricate joints,
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    regulate temperature,
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    and to nourish the brain and spinal cord.
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    Water isn't only in our blood.
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    An adult's brain and heart are almost
    three quarters water.
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    That's roughly equivalent to the amount
    of moisture in a banana.
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    Lungs are more similar to an apple at 83%.
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    And even seemingly dry human bones
    are 31% water.
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    If we are essentially made of water,
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    and surrounded by water,
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    why do we still need to drink so much?
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    Well, each day we lose two to three liters
    through our sweat,
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    urine,
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    and bowel movements,
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    and even just from breathing.
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    While these functions
    are essential to our survival,
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    we need to compensate for the fluid loss.
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    Maintaining a balance water level
    is essential to avoid dehydration
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    or over-hydration,
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    both of which can have devastating
    effects on overall health.
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    At first detection of low water levels,
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    sensory receptors
    in the brain's hypothalamus
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    signal the release
    of antidiuretic hormone.
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    When it reached the kidneys,
    it creates aquaporins,
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    special channels that enable blood
    to absorb and retain more water,
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    leading concentrated, dark urine.
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    Increased dehydration can cause
    notable drops in energy,
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    mood,
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    skin moisture,
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    and blood pressure,
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    as well as signs of cognative impairement.
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    A dehydrated brain works harder
    to accomplish the same amount
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    as a normal brain,
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    and it even temporarily shrinks
    because of its lack of water.
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    Over-hydration, or hyponatremia,
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    is usually caused by overconsumption
    of water in a short amount of time.
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    Athletes are often the victims
    of over-hydration
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    because of complications
    in regulating water levels
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    in extreme physical conditions.
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    Whereas the dehydrated brain amps
    up the production of antidiuretic hormone,
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    the over-hydrated brain slows,
    or even stops releasing it into the blood.
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    Sodium electrolytes in the body
    become diluted,
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    causing cells to swell.
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    In severe cases,
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    the kidneys can't keep up with
    the resulting volumes of dilute urine.
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    Water intoxication then occurs,
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    possibly causing headache,
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    vomitting,
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    and in a rare instances, seizures
    or death.
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    But that's a pretty extreme situation.
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    On a normal, day-to-day basis,
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    maintaining a well-hydrated system
    is easy to manage
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    for those of us fortunate enough
    to have access to clean drinking water.
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    For a long time, conventional wisdom said
    that we should drink eight glasses a day.
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    That estimate has since been fine-tuned.
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    Now, the consensus is that the amount
    of water we need to imbibe
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    depends largely on our weight
    and environment.
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    The recommended daily intake varies from
    between 2.5-3.7 liters of water for men,
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    and about 2-2.7 liters for women,
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    a range that is pushed up
    or down if we are healthy,
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    active,
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    old,
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    or overheating.
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    While water is the healthiest hydrator,
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    other beverages,
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    even those with caffeine
    like coffee or tea,
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    replenish fluids as well.
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    And water within food makes up
    about a fifth of our daily H20 intake.
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    Fruits and vegetables like strawberries,
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    cucumbers,
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    and even broccoli are over 90% water,
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    and can supplement liquid intake while
    providing valuable nutrients and fiber.
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    Drinking well might also have various
    long-term benefits.
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    Studies have shown that optimal hydration
    can lower the chance of stroke,
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    help manage diabetes,
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    and potentially reduce the risk
    of certain types of cancer.
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    No matter what, getting the right amount
    of liquid makes a world of difference
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    in how you'll feel,
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    think,
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    and function day to day.
Title:
What would happen if you didn’t drink water? - Mia Nacamulli
Speaker:
Mia Nacamulli
Description:

more » « less
Video Language:
English
Team:
closed TED
Project:
TED-Ed
Duration:
04:52

English subtitles

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