there are a lot of popular diets out
there so we thought we create a simple
video investigating which ones are
scientifically sound and actually work
from the outside it seems like a simple
equation your weight is determined by
the balance between the calories you
take in and the calories you burn by
changing what you eat or your activity
level you can tip this equation towards
weight gain or loss which brings us to
our first category of diets calorie
restriction companies like Weight
Watchers claim you can eat whatever you
want as long as you stay below a
prescribed number of daily calories
getting all your calories from junk food
is technically allowed but from a health
perspective it's important to think
about the nutritional value of the foods
too if you don't you risk heart problems
nutrient deficiencies and chronic health
issues calorie restriction with optimal
nutrition or cron diets generally reduce
their caloric intake by 20% while still
meeting the daily nutritional
requirements for example instead of
having a whole apple a cron dieter might
just have the apples skin which contains
most of the nutrients if used properly
and not excessively calorie restriction
can be a safe and effective tool for
weight loss next up is carb restriction
many diets like the South Beach Atkins
or Zone diet suggest that carbs are the
enemy of the Fit Body you've always
dreamed of the ideology claims that when
more carbs are taken in then burned off
the liver converts them into fats but
for most healthy reasonably active
people
carbs are broken down to glucose and
transported to the cells for energy very
little is actually turned into fat in
response to excessive glucose the body
uses insulin to turn it into glycogen
which is stored in the liver and muscles
this glycogen may later be broken down
in times of low glucose to refuel the
body but the type of carbs you eat do
matter those from simple sugars like
honey fruit or sugar are more readily
turned into triglycerides or fat then
complex carbs like whole grains and
veggies if you consistently eat way more
than necessary and most calories are
from simple carbs then these will be
converted to fat low carb diets often
have extreme restriction at first no
starches like bread or pasta and no
sugars including from fruits or even
alcohol this can lead to some intense
side effects including
to pation dry mouth bad breath fatigue
dizziness and nausea in studies carb
restriction dieters tend to lose weight
faster initially compared to those
simply using calorie restriction but
this is likely due to water loss which
returns in later phases when you're
encouraged to eat normally again on top
of this the Atkins diet for example
promotes caloric intake from high fat
and high protein sources which means
meats cheeses cream butter and losing
weight sounds pretty good right but many
doctors show concerns over the high
intake of saturated fat that it may lead
to more bad cholesterol and therefore an
increased risk of heart disease
some claim these diets are dangerous and
unhealthy given that they promote the
limitation of foods like carrots sweet
potatoes or apples that provide the body
with important micronutrients and
vitamins instead people require
supplements which the body is not able
to absorb as effectively as vitamins
minerals and micronutrients and whole
foods then there are high protein diets
the main principle is that protein rich
foods are not as easily broken down by
the body and take more energy to digest
the link ARB rich food this means you
won't feel hungry again as quickly and
you're more likely to run a caloric
deficit than if you ate the same number
of calories from carbs the Paleo diet
for example suggests that 10,000 years
ago agriculture was introduced and the
human diet changed from hunter-gatherers
eating primarily meat wild fruits
veggies and nuts to diets containing
more grains and as a result some believe
the human body isn't designed to digest
these processed foods like grains dairy
and breads some also believe that grains
lead to inflammation related health
problems but this is largely untrue
except in the case of people with celiac
disease but because of its
straightforward guidelines many find it
easy to follow and it does promote more
nutrient absorption
however as paleo cuts out all grains and
legumes we lose an important source of
dietary fiber necessary to keep our
bowels running smoothly not to mention
the high protein leads to nitrogen
production
stinky farts add to that constipation
which allows your digestive material to
sit longer in the large intestine and
continuing to decompose and yep even
smell your farts there is another class
of diets we might call the just stop
eating diets those looking to get slim
quick might be tempted to only eat
cabbage soup for seven days or do the
Master Cleanse diet which only allows
the salt water in the morning and a
concoction of water maple syrup lemon
and cayenne pepper through the day and a
laxative tea at night but these diets
are exceptionally unhealthy not only is
most of your weight loss from water
weight but there are many side effects
such as dizziness fatigue dehydration
and nausea the Master Cleanse can even
lead to a white tongue which some claim
is the toxins leaving your body
but it's actually due to swelling and a
yeast infection of the mouth and after
going through all that you're likely to
gain any weight loss after stopping then
of course there are straight-up crazy
diets like eating cotton balls dipped in
soup or juice so that you feel fall
which of course provides hardly any
nutritional content and can cause
intestinal blockages which requires
surgical intervention or how about the
sleeping beauty diet where you just
sleep the candy if you're always asleep
the truth is most diets focusing on
quick dramatic results also have a yo-yo
effect where you lose initial weight but
slow down your metabolic rate so your
body starts burning less calories and
then when you start eating again there's
all the weight back and often more after
following contestants from the show with
the Biggest Loser for six years of some
of which who had lost hundreds of pounds
in those seven months scientists noticed
something interesting not only did most
of the participants in the study regain
their weight but their metabolic rates
changed one man in particular now burns
eight hundred fewer calories a day than
would be expected for a man his size
this is six years after leaving the show
showing how extreme measures to lose
weight while they may be successful at
the time have long lasting impacts on
your metabolism making it harder to keep
off weight in the future the hard truth
is that even using many of the principal
diets about
7% of people regain everything lost and
sometimes more within three years if you
want to lose weight
finding a diet that works for you and
keeps you motivated with small
incremental changes is important of
course a number on a scale doesn't
measure how healthy a person is though
many struggle with this perception if
food and way preoccupations are a
problem for you or someone you know
check out the description of this video
for links with more information and
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