It is surprising that with the interest and near obsession
Americans have with weight, the obesity rates seem to continue to climb or at
the very best remain constant. There are many ways to measure weight; Americans
regularly climb on their scales to measure their weight desperately hoping to
see a drop in the numbers. This is difficult to do without the necessary
lifestyle changes, but that will be addressed as we progress.
As prior mentioned there are many ways to measure weight,
but the most common and the way in which individuals are identified as
underweight, overweight and Obese is through BMI (Body Mass Index). According
to the CDC, BMI is the estimated measurement of an individual’s body fat based
on their weight divided by height in kilograms and meters (CDC.gov 2015). Is
based on the individual results of these measurements that the terms
underweight, overweight and obese come from.
Being underweight it characterized as having a BMI of 18.5
or less, and was responsible for high number of premature deaths. Now
developing and starving nations, being underweight is a rare natural
occurrence. In the U.S, most cases of underweight patients are the result of
eating disorders like Anorexia nervosa and bulimia nervosa. Both disorders are
distinctively different, but can stem from the same phobia of gaining weight
(Sizer & Whitney 2013). These disorders are very dangerous and are becoming
a public health issue as more and more young individuals are affected by the
popular self-hating image of their weight and therefore are under a lot of
pressure to look a certain way (Anspaugh et al 2011). There are several health
implications with being underweight, as underweight people have no general
reserve of nutrients. They are at risk of death from starvation, if they are in
any situation in which they have to go without food for some time (Sizer &
Whitney 2013). Underweight women often become amenorrheic, meaning they stop
having a menstrual cycle and as such also experience infertility until they
gain some weight (Anspaugh et al 2011). The adipose fat cells in the body have
many benefits; they create insulation in the body and serve as a cushion to the
body’s organs to absorb shock. Underweight individuals are not privy to these
benefits, as they do not have sufficient adipose fat (Anspaught et al 2011).
This is an unhealthy image to present to young women.
Underweight individuals are encouraged to gain weight,
however the best treatment would be to prevent being underweight to begin with.
As prior mentioned in this nation, naturally being underweight it rare, most
occurrences are due to unhealthy body image and eating disorders. The
environment and family plays a big role in the way individuals see their
weight, especially young women. The obsession with being model thin is all over
the media, depicting an unhealthy and even dangerous body image to young
Americans, therefore parents, teachers and caregivers need to constantly
reinforce the beauty of a healthy body weight and encourage healthy eating and
physical behaviors. If more young people felt proud of their weight and the
skin they are in there would be a lot less underweight people (Sizer &
Whitney 2013).
The issues of overweight and obesity will be addressed
together as they are so closely related. As prior mentioned there are few
natural occurrences of underweightness, because most people are naturally
conditioned to gain weight. This of course is not to imply that we are by any
means slaves to our genetics, in fact in Ontario’s agrarian Amish society where
a good meal is usually followed by dessert, there men and women still maintain
a good body weight due their daily lives include a good amount of physical
activity (Gray 2010).The term
overweight is characterized by a BMI of 25.0 to 29.9, while obesity is defined
as over fatness characterizes by a BMI 0f 30.0 or higher (Anspaugh et al
2011).We have been discussion the
implications of having too much body fat in the weeks past. There societal
implications, as overweight and obese individuals are often discriminated
against. More important are the health implications of too much body fat and
their relation to many chronic diseases today. As BMI increases so does the risk of mortality and even slightly
higher than the risk of mortality to underweightness (there is a high risk
nonetheless) (Sizer & Whitney 2013). Overweightness is but a hop and skip
away from obesity, and because there are so many diseases associated with
obesity like heart diseases, diabetes, osteoporosis and metabolic syndrome
obesity truly pose a great public health risk (Anspaugh et al 2011).
The same preventative measure to underweightness applies to overweightness and obesity as well, the environment and home life play a big role in the eating habits, therefore healthy eating habits promoting healthy nutrition dense foods and portion control should be taught and encouraged. Physical activity is also an important life long habit that should be encouraged to aid a healthy body weight (Sizer & Whitney 2013).
Here is a link to the Mayo Clinics, helpful tips on Obesity prevention.
Every living thing needs energy via nutrients to survive,
even the most seemingly inanimate organisms like plant require the nutrient
they get from sunlight and water to survive and even thrive. Humans being, the
most advanced of living organisms are no different. In fact, the proper
nourishment of humans is a bit more sophisticated than just consuming any food.
Individuals require all necessary nutrients, the Macros or energy yielding. In
addition the micronutrients vitamins and minerals are just as vital for their
supporting and protective properties
As previously implied there are six classes of
nutrients that broken into energy yielding (Macronutrients), and supporting
(micronutrients), these nutrients are also considered essential nutrients
because they cannot be produced by the body (Anspaugh et al), and are thus
required to be consumed through food. The four Macronutrients or energy
yielding nutrients are indirectly derived from the sun, either through the
consumption of plant based foods or, plant eating animal foods, they are
“organic; that is, the nutrients contain the element carbon derived from living
things” (Sizer & Whitney 2013 p 7). The macronutrients are:
Carbohydrates: which are made up of sugar units
(saccharides) and are broken down in the body as such (Richards 2009).
Carbohydrates can be simple (Simple sugars, quickly digested) or complex
(starches and fibers, take more time to be broken down), however whichever from
it comes in is broken down to its simplest form, glucose and used as energy in
the body. Most if not all carbohydrates are plant based and the main source of
energy yielding nutrients. Some foods that are sources of carbohydrates are
grains, vegetables, fruits and legumes (Anspaugh et al 2011).
The next energy yielding macronutrient is Protein,
which is in addition to carbon also contains hydrogen and nitrogen (Anspaugh et
al 2011). Protein aids cell growth, tissue repair, as well as maintains the
functionality and regulation of cells, organs, hair, skin and nails. The
building blocks of proteins are amino acids, of which there are approximately
20. 11 are non-essential meaning they can be produced by the body; the
remaining 9 however must be acquired from food. Even though protein is an
energy-yielding nutrient, it would be ineffective as the only source of energy
as it does not yield enough, it must be coupled with other nutrients. Foods
that are a source of protein are meat, fish, milk, eggs, pulses, legumes, nuts
and seeds among others.
Another energy yielding macronutrient is Fat, which are
oils, sterols and waxes. They not water soluble (water and oil don’t mix), and
are high in calories, which is why a small amount of fat is recommended in
daily diet. Fat is a however an essential component of all cells, and aids in
the synthesis and repair of vital cell transport and absorption of fat-soluble
vitamins. Fats that remain liquid at room temperature like olive oil, rapeseed
oil (canola), grape seed oil; sunflower oils etc. are generally better than
those that solidify like butter, margarine and coconut. Fat consumption should
be kept to a minimum, especially if carbohydrate consumption high.
While all nutrients are important one of the most
important is water, which performs many functions. The human body can survive
up to 3 weeks without food, however it can only survive about 3 days without
water, that how important water is to the body. Water is essential for the body
to function properly, it makes up about two thirds of the human body an every
chemical reaction, lubrication, nutrient transportation and removal of toxins
and waste requires water (Richards 2009). It is recommended that 6-8 glasses of
water be drunk each day, and many fruits and vegetables also contain water.
Micronutrients like vitamins, minerals and trace
elements are also essential for proper bodily function, however they are only
needed in small quantities (Richards 2009).
Vitamins are organic, containing carbon and can be
found in plant or animal based foods, as prior mentioned they are only needed
in small amounts for proper function of the body (Anspaugh et al 2011).
Vitamins are essential nutrients because the body cannot produce them and as
such have to be consumed through daily diet, “Unlike carbohydrates, fats, and
proteins, vitamins yield no energy. Instead, some serve as catalysts that
enable energy nutrients to be digested, absorbed, and metabolized (Anspaugh et
al 2011. p191). Some vitamins interact with minerals to aid their absorption,
while some act as antioxidants to neutralize free radicals and toxins in the
body (Anspaugh et al 2011).
Minerals are also simple, but important nutrients,
and like vitamins are only needed in minute quantities. The compositions of
mineral are inorganic, and they are found in rocks or soil. However they can
also be consumed through plants and animals, as plants can absorb them from the
ground and plant-eating animals can ingest and digest them (Richards 2009).
Minerals like vitamins are not energy yielding, and “As inorganic compounds,
they lack the complexity of vitamins, but they fulfill a variety of functions.
For example, sodium and potassium affect shifts in body fluids, calcium and
phosphorus contribute to the body’s structure, iron is the core of hemoglobin
(an oxygen-carrying compound in the blood), and iodine facilitates production
of thyroxin” (a hormone that influences metabolic rate) (Anspaugh et al P197).
There
is much to learn about nutrition and physical activity with regards to
wellness, however it matters not without the knowledge of how the body converts
food into energy and the process it undergoes to do this. From infancy, human
beings are taught that food is required for nourishment and energy by the body,
however this course has specified that it is actually the nutrients from food
that is needed by the body to produce energy. The digestive system is and
important component in this process. Here is a video on how it works.
According to the required text, Nutrition: Concepts and Controversies when the body needs food, the
brain sends a signal to the consciousness which illicit the feeling of hunger
(Sizer & Whitney 2013), this is but a precursor to the digestive process.
When food id introduced in to the body, “The digestive system transports
nutrients, water and electrolytes from food into the body’s inner environment…
Food provides a source of energy for the production of adenosine triphosphate
(ATP) by cells so that the functions of active transport, contraction,
synthesis and secretion, which are energy-dependent activities, can be carried
out (Sherwood 2013). Food is also required so that body tissues can be repaired
and renewed and for this to occur, food needs to be processed into a form that
the body can use readily” (Hendry et al 2014, par 17).
In other words the purpose of the digestive system is
to break down food to its simplest form, so that it can be absorbed and
transported to all parts of the body that need the necessary nutrient. While
some nutrients can be produced in the body, most need to be ingested in the
form of food. And those produced by the body, require energy for the production
process. Some evolutionary scientists might imply that the digestive system is
a sophisticated piece of ‘equipment’, which by its evolution provides new and more
effective opportunities for nutrition (Broderick 2015).
The digestive system consists from an array of organs
beginning from the mouth and ending at the anus, and is mostly run by the
autonomic nervous system (Johnstone et al 2014). The organs, which make up the
digestive system include the : Mouth, Pharynx, Esophagus, Stomach, Small
intestine, Large intestine, Rectum and anal canal. As food passes through the
digestive tract, each organ performs a function to aid digestion and the
absorption of nutrients. Other accessory organs like the Teeth, Tongue, major
pairs of salivary glands, Liver, Pancreas, Gall bladder also assist the
digestive system in this of consuming and digesting food, absorbing nutrients
and expelling waste from the body. The digestive system works in two ways to
perform these functions, mechanical and chemical.
The mechanical aspect of digestion food being broken
down into its smaller particles, mixed up with digestive juices as it moves
along the gastrointestinal tract, and the rest removed from the body as feces
(Hendry et al 2014). In greater detail, mechanical digestion begins in the
mouth, where pieces of food are torn apart and mixed with saliva. At this stage
chewing is very important, because it allows enzymes and digestive acids to
better break down food. Saliva also coats and moistens the food, making it
easier to pass down the esophagus (Sizer & Whitney 2013). The masticated
food, known as bolus is then transported through the esophagus to the stomach,
where it is held and ground into a fine paste to aid the remainder of the
digestive process. Water and digestive juices is also added to the finely
ground up food as well, now forming chyme. The chime through the muscular
pyloric valve, is forcefully squirted into the small intestine a little at a
time. This process is completed a few hours after the meal is consumed. Most of
digestion and the absorption of nutrients occur in the small intestine, which
is about six meters long. The small intestine is designed to maximize the absorption
of nutrients with its maximal surface area consisting of villi and microvilli
(Johnstone et al 2014). The remainder, which is not able to be digested is then
moved to the large intestine. Regardless of its name, the large intestine or
colon isonly about 1.5m long and
continues from the end of the ileum, the latter part of the small intestine to
the anus (Johnstone et al 2014). Even though the main function of the large
intestine is to expel waste from the body, there is still some absorption of water
and minerals prior donated by former digestive organs leaving behind undigested
materials as fecal matter excreted by the body as waste (Sizer & Whitney
2013).
The chemical aspect of digestion “occurs when food is
broken down into absorbable units so that they can pass through the intestinal
mucosa into the circulatory system (Hendry et al 2014, par 17). In chemical
digestion, food is hydrolyzed using enzymes from different organs. This process
also begins in the mouth, as an enzyme in saliva begins breaking down starch
from carbohydrates and some fat, particularly milk fat (Sizer & Whitney
2013). The digestion of protein does not begin until it reaches the stomach,
here the release of gastric juices; which is a mixture of water, enzymes and
hydrochloric acid activates a protein-digesting enzyme to begin the digestion
of protein. In the small intestine, the work that was begun in the mouth and
stomach gets underway as the gallbladder and pancreas secrete bile and
pancreatic juices in just the right amounts to support the digestive enzymes in
the small intestine. Sugar and starch are broken down to monosaccharaides and
absorbed. Fibers are not digested, however they bind to fat and some minerals
on their way to the large intestine. Fats are broken down to fatty acids by the
bile from the liver by way of the gallbladder and are absorbed as such.
Proteins are broken down into amino acids by enzymes in the small intestine and
pancreas before it is absorbed. The prior mentioned fiber is relieved of more
water and minerals before it excreted as part of the feces (Sizer & Whitney
2013).
Without a doubt the digestive tract/system is a very
important part of every human body, however not much consideration is given to
it until there is discomfort and sometime even that is ignored. According to
the required text in A Letter from your
Digestive Tract, many food choices and the way they are consumed contribute
greatly to discomforts and digestive disorders. Consuming foods to fast can
cause hiccups, while consuming too much of new foods can lead to excessive
flatulence, which could be serious. In addition, overeating causes the acidic
juices to rise back up the esophagus causing heartburn. However some more
serious conditions, like hernia, and ulcers could be the cause and should be
checked out by a physician instead of self-medicating, constipation and
diarrheas are also signs that the digestive system is afflicted. To avoid these
conditions among others, healthy food choices should be consumed regularly. New
foods should be introduced slowly, a little at a time, and Foods should be
eaten in a relaxed manner (Sizer & Whitney 2013). The digestive system
works for the human body, and ensures that food taken in is broken down
(digested), and absorbed to produce energy for every bodily function; the most
humans can do is help it along by feeding the body right.
References:
Anspaugh, D. J., Hamrik, M. H., & Rosato, F. D. (2011).
Wellness concepts and
applications. (8th
ed.). New York: NY, McGraw-Hill Higher Education
Broderick, N. A. (2015). A common origin for immunity and
digestion. Frontiers In
Immunology, 61-3.
Hendry, C., Farley, A., McLafferty, E., & Johnstone,
C. (2014). The digestive system: part
2.Nursing Standard, 28(25), 37-44.
Johnstone, C., Hendry, C.,
Farley, A., & McLafferty, E. (2014). The digestive system: part
1.Nursing Standard, 28(24), 37-45.
Richards, S. (2009). The building blocks of a healthy
diet. Practice Nurse, 38(3), 12-17.
Retrieved from EBSCOhost.
Richards, S. (2009). The building blocks of a healthy
diet Part 2. Practice Nurse, 38(4), 29-33. Retrieved from EBSCOhost
Sizer, F. & Whitney, E. (2013). Nutrition:
Concepts and Controversies (13th ed.). Mason, OH: Cengage Learning.
