ABCD OF Nutrition
Nutrition is essential materials
to live, there are six major classes of materials 1.Fat
2.Carbohyadrates (& fiber) 3.Protetin 4.Vitamins 5.Minerals 6.
Water.
These nutrient classes can be
generally grouped into the categories of macronutrients (needed in
relatively large amounts), and micronutrients (needed in smaller
quantities). The macronutrients are carbohydrates, fats, fiber,
proteins and water. The other nutrient classes are micronutrients. The
macronutrients (excluding fiber and water) provide energy, which is
measured in kilocalories, often called "Calories" and written with a
capital C to distinguish them from small calories. Carbohydrates and
proteins provide four Calories of energy per gram, while fats provide
nine Calories per gram. Vitamins, minerals, fiber, and water do not
provide energy, but are necessary for other vital functions. Other
micronutrients not categorized above include antioxidants and
phytochemicals. Most foods contain a mix of some or all of the nutrient
classes. Some nutrients are required on a regular basis, while others
are needed less frequently. Poor health can be caused by an imbalance
of nutrients, whether an excess or a deficiency.
1.Fat 2.Carbohydrate 3.Protein 4.Vitamins 5.Minerals 6.Water. 7.Phytochemicals 8.Antixidants
1. FAT- Fat provides 9 calories from one
gram. Fats are composed of fatty acids (long carbon/hydrogen chains)
bonded to a glycerol. Fat is classified as saturated or unsaturated.
Saturated fats have all of their carbon atoms bonded to hydrogen atoms,
whereas unsaturated fats have some of their carbon atoms double-bonded
in place of a hydrogen atom. Unsaturated fats are generally healthier
than saturated fat. Saturated fat is typically solid at room
temperature (such as butter), while unsaturated fat is a liquid (such
as olive oil). Unsaturated fats may be further classified as
monounsaturated (one double-bond) or polyunsaturated (many
double-bonds). Certain fatty acids are essentials to maintain health
because it cannot be synthesized in body, it must be consumed in diet.
Omega 3 and Omega 6 are essentials fatty acids. Omega-3 fatty acids are
another important group of essential fatty acids. Together, omega-3 and
omega-6 fatty acids play a crucial role in brain function as well as
normal growth and development. EFAs belong to the class of fatty acids
called polyunsaturated fatty acids (PUFAs). They are generally
necessary for stimulating skin and hair growth, maintaining bone
health, regulating metabolism, and maintaining reproductive capability.
Deficiencies in EFAs can lead to reduced growth, a scaly rash called
dermatitis, infertility, and lack of ability to fight infection and
heal wounds.It is important to maintain an appropriate balance of
omega-3 and omega-6 (another essential fatty acid) in the diet, as
these two substances work together to promote health. Omega-3 fatty
acids help reduce inflammation, and most omega-6 fatty acids tend to
promote inflammation. An inappropriate balance of these essential fatty
acids contributes to the development of disease while a proper balance
helps maintain and even improve health. A healthy diet should consist
of roughly 2 - 4 times more omega-6 fatty acids than omega-3 fatty
acids.Good sources of essential fatty acids include: fish, flax seeds,
hemp seeds, soy beans, pumpkin seeds, sunflower seeds, and walnuts.
2. Carbohydrates
Carbohydrate provides 4 calories
from one gram.Carbohydrates are the most abundant class of organic
compounds found in living organisms. Chemically, carbohydrates are
organic molecules in which carbon, hydrogen, and oxygen. Carbohydrates
may be classified as monosaccharides, disaccharides, or polysaccharides
by the number of monomer (sugar/saccharide) units they contain.
Monosaccharides contain 1 sugar/saccharide unit, disaccharides contain
2, and polysaccharides contain 3 or more. Polysaccharides are often
referred to as complex carbohydrates because they are long chains of
sugar units, whereas monosaccharides and disaccharides are simple
carbohydrates. The difference is important to nutritionists because
complex carbohydrates take longer to metabolize since their sugar units
are processed one-by-one off the ends of the chains. Simple
carbohydrates are metabolized quickly and thus raise blood sugar levels
more quickly resulting in rapid increases in blood insulin levels
compared to complex carbohydrates.
Fiber-Fiber does not provide any
calorie. Dietary fiber consists mainly of cellulose, a large
carbohydrate polymer, which is indigestible because humans do not have
enzymes to digest it. Whole grains, fruits (especially plums, prunes,
and figs), and vegetables are rich in dietary fiber. Recommended intake
of daily fiber is 25-30 grams per day to prevent constipation,colon
cancer and to reduce blood cholesterol.
3. Protein
One gram protein provides 4
calories. Protein is composed of amino acids that are the body's
structural materials. The body requires amino acids to produce new body
protein (protein retention) and to replace damaged proteins
(maintenance) that are lost in the urine. Amino acid requirements are
classified in terms of essential (body cannot produce them) and
non-essential (body can produce them from other nitrogen containing
compounds) amino acids. Consuming a diet that contains adequate amounts
of essential (but also non-essential) amino acids is particularly
important for growing. Essential amino acids are phenylalanine, valine,
threonine, tryptophan, isoleucine, methionine, leucine, and lysine.
Dietary sources of protein include meats, tofu and other soy-products,
eggs, grains, legumes, and dairy products such as milk and cheese.
4. Vitamins
Vitamins are organic compounds.
They are required in small amounts. Vitamins have diverse biochemical
functions, including function as hormones (e.g. vitamin D),
antioxidants (e.g. vitamin A), and mediators of cell signaling and
regulators of cell and tissue growth and differentiation. Vitamins are
classified on the basis of solubility medium 1) Water soluble - Vitamin
C & eight Vitamin B are soluble in water so they are known as water
soluble. 2) Fat soluble - Vitamin A, D, E, K are absorbed through the
intestinal tract with the help of lipids (fats).RDA (recommended daily
allowance) is used to determine the daily intake of vitamins and
minerals, RDAs are dietary standards(dose) established by the food and
nutrition board of national academy of sciences.
5. Minerals
Minerals are inorganic compounds.
The term "mineral" is archaic, since the intent of the definition is to
describe ions, not chemical compounds or actual minerals. Minerals has
various functions in body that includes but not limited, to build teeth
and bones, hormones and enzymes formations ,to maintain acid-base
balance,transfering nervous system message. Some dietitians recommend
that these heavier elements should be supplied by ingesting specific
foods. Minerals are classified on the basis of their require
quantity,1)Macro minerals - minerals which are needed in large dose
,more than 200 mg per day, for example-
calcium,magnesium,phosphorus,potassium,sulphur,sodium,chloride. 2)
Trace minerals - minerals which are needed in very small quantity, per
day, for example - iron, zinc , selenium, manganese , molybdenum
,iodine, copper , chromium ,fluoride.
6. Water
About 70% of the non-fat mass of
the human body is made of water. Water is vital both as a solvent in
which many of the body's solutes dissolve and as an essential part of
many metabolic processes within the body. Water is also central to
photosynthesis and respiration. Water is also central to acid-base
neutrality and enzyme function. To function properly, the body requires
between one and seven liters of water per day to avoid dehydration; the
precise amount depends on the level of activity, temperature, humidity,
and other factors. With physical exertion and heat exposure, water loss
will increase and daily fluid needs may increase as well. Some experts
assert that 8-10 glasses of water (approximately 2 liters) daily are
the minimum to maintain proper hydration. United States National
Research Council in general recommended (including food sources): 2.7
liters of water total for women and 3.7 liters for men. Specifically,
pregnant and breastfeeding women need additional fluids to stay
hydrated. According to the Institute of Medicine-who recommend that, on
average, women consume 2.2 litres and men 3.0 litres-this is
recommended to be 2.4 litres (approx. 9 cups) for pregnant women and 3
litres (approx. 12.5 cups) for breastfeeding women since an especially
large amount of fluid is lost during nursing. For those who have
healthy kidneys, it is rather difficult to drink too much water, but
(especially in warm humid weather and while exercising) it is dangerous
to drink too little. People can drink far more water than necessary
while exercising. People who exercise should drink 8-16oz before (15
minutes) exercise, 8-10 oz during (after every 15 minutes) exercise and
16-32 oz after exercise.
7. Phytochemicals
Phytochemicals are plant- or
fruit-derived chemical compounds. "Phytonutrients" refer to
phytochemicals or compounds that come from edible plants.
Phytochemicals in freshly harvested plant foods may be destroyed or
removed by modern processing techniques, possibly including cooking.
For this reason, industrially processed foods likely contain fewer
phytochemicals and may thus be less beneficial than unprocessed foods.
8. Antioxidants
An antioxidant is a molecule
capable of slowing or preventing the oxidation of other molecules.
Oxidation is a chemical reaction that transfers electrons from a
substance to an oxidizing agent. Oxidation reactions can produce free
radicals, which start chain reactions that damage cells. Vitamin A ,C
,E, Carotenoids,Sulphur,selenium has antioxidant properties.
Blog by
Dr.Raju Bhandari
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