Nutrition and You:: 15 Works Cited
Length: 3612 words (10.3 double-spaced pages)
Nutrition is the relationship of foods to the health
of the human body . Proper nutrition means that you are receiving enough
foods and supplements for the body to function at optimal capacity. It is
important to remember that no single nutrient or activity can maintain
optimal health and well being, although it has been proven that some
nutrients are more important than others. Nutrition plays a critical role in
athletic performance, but many active people do not eat a diet that helps
them do their best. Without a basic understanding of nutrition, popping a
pill seems easier than planning a menu. In reality, there is no pill, potion,
or powder that can enhance your performance like the right foods and
All of the nutrients are necessary
in different amounts along with exercise to maintain proper health. There
are six main types of nutrients used to maintain body health. They are:
carbohydrates, fats, proteins, vitamins, minerals, and water . They all must
be in balance for the body to function properly. There are also five major
food groups. The groups are: fats and oils, fruits and vegetables, dairy
products, grains, and meats.
Exercise is also an important part of nutrition.
Exercise helps tone and maintain muscle tissue and ensure that the body?s
organs stay in good condition. Healthy eating without exercise will not
result in good nutrition and a healthy body - neither will exercise without
nutrition. The most important thing about exercise is that it be practiced
regularly and that it be practiced in accompaniment with a healthy diet. It
is also desirable to practice more that one sport as different sports exercise
different areas of the body.
Carbohydrates, proteins, and fats are the sources of energy for the
body. To have enough energy you need to consume enough energy.
Getting adequate calories is one of the keys to an ergogenic, or
performance-enhancing, diet. With too few calories you will feel tired and
weak, and you will be more prone to injuries. The contained energy is
expressed in calories.
There are 9 calories per gram in fat and there are about 4 calories
per gram in proteins and carbohydrates . Carbohydrates are the main
source of energy for the body. A high-carbohydrate diet increases stores of
glycogen, the energy for muscles, and improves overall athletic
performance. The bulk of the day's calories--60% to 70%--should come
from carbohydrates such as bread, cereal, grains, pasta, vegetables, and
fruit.Different carbohydrate foods can affect your energy level in different
ways. Digestion rates are expressed as a "glycemic index." Foods with a
high glycemic index release energy into the bloodstream rapidly, while
foods with a moderate or low glycemic index release their energy more
slowly . However, beware of the old idea that simple
sugars are always digested rapidly and cause wide swings in blood sugar,
and that all complex carbohydrates like bread are digested more slowly
and don't cause blood sugar fluctuations. This turned out to be wrong. If
you exercise for longer than an hour, you can begin to
deplete your muscles of glycogen. By consuming 30 to 75 grams per hour
of high-glycemic-index carbohydrate in liquid or solid form when you
exercise, you can minimize this effect.
This energy is mostly used for muscle
movement and digestion of food. Some sources of carbohydrates are :
grains, fruits, vegetables, and anything else that grows out of the ground.
The energy in carbohydrates is almost instantly digested. This results in a
quick rise in blood sugar which is soon followed by a drop in blood sugar
which is interpreted by the body as a craving for more sugars. After a long
workout or competition, your depleted muscle glycogen stores must be
replenished, especially if you will be exercising again within the next 8
hours. Eat at least 50 grams of high-glycemic-index carbohydrate just
after exercise, and consume a total of at least 100 grams of high-glycemic-
index carbohydrate in the first 4 hours afterward. Moderate-glycemic-
index foods may be added for the next 18 to 20 hours, with a goal of
consuming at least 600 grams of carbohydrate during the 24 hours after an
intense workout or competition. This sugar low may also result in fatigue,
dizziness, nervousness, and headache.However, not all carbohydrates do
this. Most fruits, vegetables, legumes, and whole grains are digested more
slowly. Oatmeal is an excellent choice for an inexpensive carbohydrate-
Fat is definitely an important energy source, particularly for athletes
involved in prolonged, low-intensity activity. (For high-intensity, short-
term activity, carbohydrate is the primary fuel source.) About 20% of the
calories in a performance-enhancing diet should come from fat (1), most
of it unsaturated fat like vegetable and fish oils. Fats, which are lipids, are
the source of energy that is the most concentrated.
Fats produce more that
twice the amount of energy that is in carbohydrates or proteins. Besides
having a high concentration of energy, fat acts as a carrier for the fat
soluble vitamins, A, D, E, and K. Also, by helping in the absorption of
vitamin D, fats help make calcium available to various body tissues, in
particular, the bones and teeth. Another function of fat is to convert
carotene to vitamin A. Fat also helps keep organs in place by surrounding
them in a layer of fat. Fat also surrounds the body in a layer that preserves
body temperature and keeps us warm. One other function of fat is to slow
the production of hydrochloric acid thereby slowing down digestion and
making food last longer. Some sources of fats are meats and nuts as well
as just plain oils and fats.
Protein plays a minor role in energy production, contributing only
5% to 10% of the energy used during prolonged exercise. Although the
current recommended dietary allowance for protein is about 0.4 grams per
pound of body weight per day, most active people need slightly more. And
athletes involved in heavy resistance exercise or prolonged endurance
events may require 0.7 to 0.9 grams per pound per day. Even this amount
is relatively easy to eat, since 3 ounces of fish or chicken, 1 1/2 cups of
tofu, or 1 1/2 cups of garbanzo beans contain 20 to 24 grams of protein.
As an active person, you need protein for building muscles, repairing
tissues, growing hair and nails, making hormones, and assisting in
numerous other functions that contribute to a strong and healthy body.
Protein is found in many foods--such as meats and dairy products--besides
The daily amount of protein you need ranges from 0.5 to 0.9 grams
per pound of body weight per day; the higher end of the range is
appropriate for athletes who are growing, building muscles, doing
endurance exercise, or restricting calories. A 6-ounce serving of fish
provides about 40 grams of protein--a good part of the daily 75 to 135
grams of protein needed by a 150-pound athlete.The protein in fish is
among the most healthful animal sources of protein. That's because fish is
low in saturated fat, the type associated with clogged arteries and heart
disease. Saturated fat (as in beef lard and cheese) is solid at room
temperature. Fish would be unable to function if their fat were saturated
like that of many warm-blooded animals. Instead, fish store energy in the
form of polyunsaturated oils that are soft and flexible in the cool
temperatures of oceans and mountain streams.
Proteins, besides water, are the most plentiful
substance in the body. Protein is also one of the most important element
for the health of the body. Protein is the major source of building material
in the body and is important in the development and growth of all body
tissues. Protein is also needed for the formation of all hormones. It also
helps regulate the body?s water balance. When proteins are digested they
are broken down into simpler sections called amino acids. However, not
all proteins will contain all the necessary amino acids. Most meat and
dairy products contain all necessary amino acids in their proteins. Proteins
are available from both plants and animals. However, Animal proteins are
more complete and thus desirable.
As mentioned above,
there are six nutrients. All vitamins are organic food
substances that are found only in living things, plants and animals . It is
believed that there are about twenty substances that are active as vitamins
in human nutrition . Every vitamin is essential to the proper growth and
development of the body. With a few exceptions, the body cannot make
vitamins and must be supplied with them. Vitamins contain no energy but
are important as enzymes which help speed up nearly all metabolic
functions. Also, vitamins are not building components of body tissues, but
aid in the construction of these tissues. It is impossible to reliably
determine the vitamin requirements of an individual because of
differences in age, sex, body size, genetic makeup, and activity.
source of a recommendation is the RDA. The RDA makes it?s
recommendations based on studies of consumption of the given nutrient.
On the recommendation it will usually specify what size diet the
recommendation is based on, for example, a two thousand calorie per day
diet. It is harmless to ingest excess of most vitamins. However, some
vitamins are toxic in large amounts. Vitamin A is a fat soluble vitamin
which is only available in two forms. Pre-formed, which is found in
animal tissue. The other is carotene, which can be converted into Vitamin
A by animals . Carotene is found in easily found in carrots as well as other
vegetables . Vitamin A is important to the growth and repair of body
tissues and helps maintain a smooth, soft, and disease free skin. It also
helps protect the mucus membranes of the mouth, nose, throat, and lungs
which reduces the chance of infection. Another function is helping mucus
membranes combat the effects of air pollutants. Vitamin A also protects
the soft lining of all the digestive tract. Another function of vitamin A is to
aid in the secretion of gastric juices. The B complex vitamins have many
known sub-types, but they all are water soluble vitamins. The B vitamins
can be cultivated from a variety of bacteria, yeast, fungi, or molds . They
are active in the body by helping the body convert carbohydrates into
glucose, a form of sugar. B vitamins are also vital in the metabolism of
proteins and fats. They are also the single most important element in the
health of the nerves. B vitamins are also essential for the maintenance of
the gastrointestinal tract, the health of the skin, hair, eyes, mouth, liver,
and muscle tone. The intestine contain a bacteria that produces vitamin b
but milk-free diets, and taking sulfonamides or antibiotics can destroy
these bacteria . Whole grains contain high concentrations of B complex
vitamins. Also, enriched bread and cereal products contain high
concentrations of B vitamins due to a governmental intervention of the
whole food group to ensure that the nation was getting enough B vitamins
Vitamin C, also known as ascorbic acid, is a water soluble vitamin. It is
sensitive to oxygen and is the least stable of all vitamins . One primary
function of vitamin C is to maintain collagen, a protein necessary for the
formation of skin, ligaments, and bones. Vitamin C also plays a role in
healing of burns and wounds because it aids the formation of scar tissue.
It also helps form red blood cells and prevent hemorrhaging. Another
function is to prevent the disease, scurvy, which used to be seen in sailors
because of their lack of vitamin C in their diet. This was corrected by
issuing each sailor one lime per day which supplied citric acid, a source of
vitamin C. Other sources include broccoli, Brussels sprouts, Strawberries,
Oranges, and grapefruits . Vitamin E is a fat soluble vitamin which is
made up of a group of compounds called tocoherols. There are seven
forms of it but the form known as Alpha tocoherol is the most potent .
Tocoherols occur in the highest concentrations in cold pressed vegetable
oils, all whole raw seeds and nuts, and soybeans. Vitamin E plays an
essential role in cellular respiration of all muscles, especially the cardiac
and skeletal. It makes these muscles able to function with less oxygen,
thereby increasing efficiency and stamina. It also is an antioxidant, which
prevents oxidization. This prevents saturated fatty compounds from
breaking down and combining to form toxic compounds.
nutrients that exist in the body and in organic and inorganic combinations.
There are approximately seventeen minerals that are necessary in human
nutrition . Although only about four or five percent of the body weight is
mineral matter, minerals are important to overall mental and physical
health. All of the body?s tissues and fluids contain some amount of
mineral. Minerals are necessary for proper muscle function and many
other biological reactions in the body. Minerals are also important in the
production of hormones. Another important function of minerals is to
maintain the delicate water balance of the body and to regulate the blood?s
pH. Physical and emotional stress causes a strain on the body?s supply of
minerals. A mineral deficiency often results in illness, which may be
treated by the addition of the missing mineral to the diet. Calcium, a
primary mineral, is available through dairy products. In order to get all the
other minerals, one should eat protein rich foods, seeds, grains, nuts,
greens, and limited amounts of salt or salty foods. They don't contribute
energy themselves, but vitamins and minerals are integral to food
metabolism and energy production. Iron and calcium are the minerals
most commonly deficient in athletes, and strict vegetarians may be
deficient in vitamin B12. By consuming adequate calories and following
the food guide pyramid plan, your needs for all the important
micronutrients can be met.
Water is the ultimate ergogenic aid--but because the body has a poor
thirst mechanism, you must drink before you feel thirsty. Once you are
thirsty you are already slightly dehydrated, and your performance will be
To stay well hydrated, you need to drink about a quart of caffeine-
free, nonalcoholic fluids for every 1,000 calories of food you eat,
assuming you maintain your weight. To ensure that you are well hydrated
before you exercise, drink 2 cups of water or sports drink 2 hours
beforehand. To avoid dehydration during exercise, begin drinking early
and at regular intervals. For exercise lasting an hour or less, 4 to 6 ounces
of cool water every 15 to 20 minutes provides optimal fluid replacement.
During exercise that lasts longer than 60 minutes, carbohydrate-
electrolyte beverages containing 5% to 8% carbohydrate should be drunk
at the same rate to replace fluid and spare muscle glycogen. Also,
consuming sports drinks during intense activities such as soccer or
basketball may enhance performance. After exercise, replace every pound
lost during exercise with at least 2 cups of fluid.
Fiber, found only in plant foods, is an indigestible form of
carbohydrate that provides plants with structural rigidity. Fiber is
classified by its ability or inability to dissolve in water. Most plant foods
contain both types. (See "Soluble and Insoluble Fibers," below.) Both
soluble and insoluble fibers enhance the work of the intestines, but in
different ways. Following are some of the health benefits of these types of
Soluble fiber slows the absorption of sugars and starches from the
small intestine into the bloodstream. This action helps smooth out the
peaks and valleys in blood sugar levels, possibly helping to ward off type
2 ("adult onset") diabetes. For someone who already has diabetes, soluble
fiber helps control blood sugar levels
Cholesterol made by the body is an ingredient in bile, a substance
that is used in digestion and is recycled. Soluble fiber binds to bile acids in
the intestines, thereby lowering the body's cholesterol pool. Soluble fiber
can lower blood cholesterol levels by at least 5% in people with healthy
cholesterol levels, and even more in those who have elevated cholesterol.
Insoluble fiber provides bulk that helps move food residues through
the intestine, which helps prevent constipation and diverticular disease.
Insoluble fiber also flushes carcinogens, bile acids, and cholesterol out of
the system. Studies of total fiber intake (soluble and insoluble) show a
decreased risk of colon, rectal, breast, prostate, and other cancers with
consumption of a high-fiber diet.
Dietary fiber plays an important role in weight management.
Because fiber helps you feel full and slows the emptying of your stomach,
you eat less. Also, high-fiber diets tend to be low in calories and less likely
to contribute to obesity. By avoiding obesity, you lower your risks for the
development and progression of heart disease, cancer, high blood pressure,
To increase your fiber intake, make plant foods the foundation of
your diet. For packaged foods, read nutrition labels for the amount of fiber
per serving--a good source of fiber contains more than 1 gram per serving.
Refined bread and cereals usually contain less than that, and beans, whole
grains, and fiber-fortified bread and cereals usually have more (table
below). Be sure to get plenty of fluid with a high-fiber diet.
Common Fiber-Containing Foods
Food Dietary Fiber Content (grams)
Kidney beans, cooked (3/4 c) 9.3
Cereal, All Bran (1/3 c) 8.5
Prunes, dried (3 medium) 4.7
Popcorn, air popped (3 1/2 c) 4.5
Pear (1 medium) 4.1
Apple (1 large) 4.0
Orange (1 large) 4.0
Potato, baked, with skin (1 medium) 4.0
Spinach, cooked (1 c) 4.0
Sunflower seeds (1 oz) 4.0
Banana (1 medium) 3.8
Rice, brown, long-grain, cooked (1 c) 3.3
Carrots, cooked (1/2 c) 3.2
Barley, cooked (1/2 c) 3.0
Strawberries (1 c) 2.8
Bread, whole wheat (1 slice) 2.4
Cranberries (1/2 cup) 2.0
Cereal, wheat flakes (3/4 c) 1.8
Oatmeal, cooked (3/4 c) 1.6
Seaweed, nori or kombu (1 c) 1.0
Bread, white (1 slice) 0.6
Increase your fiber slowly to prevent cramping, bloating, and other
unpleasant symptoms. Be aware, too, that you can get too much fiber.
Excess fiber decreases the absorption of minerals, and large amounts over
a short time--as in supplements--can lead to a serious intestinal
obstruction. More than 50 grams per day is probably too much.
Nutrition is just one aspect of total body health. It is important to remember that on must
compliment good nutrition with good exercise and emotional health in
order to achieve complete well being. It is also important to remember that
no one part of nutrition will completely fulfill the body?s requirements for
health. Knowledge of the nutrients and their function is essential to
understanding the importance of good nutrition.
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