NUTRITION

NUTRITION

Nutrition is the study or science of howfood nourishes the body.It is the study of the foods we eat andhow they affect our body.It includes the physical components ofdigestion, emotional issues with eatingand health issues in general. It alsoincludes a little biochemistry and foodscience.

The Importance of NutritionGood nutrition enhances quality of life and helps toprevent disease.

These could bee maintained by the followingrequirements:-

Energy

Growth

Maintenance

Reproduction

Lactation

NUTRIENTS:substances in foods that your body needs to grow, to repair, and to provide energy.

CALORIES:units of heat that measure the energy used by the body and energy supplied to the body by foods.

Nutrition provides us with the calories and nutrients our bodies need for maximum energy and wellness.

Factors Influence Food Choices?1. Hunger and Appetite:Hunger: Natural need to eat and not starve.Appetite: A desire to eat..

2. Emotions:Stress, Anger, Happy, Sad, etc,

3. Environment: Family and Friends

4. Cultural and Ethnic Background:Race, Religion, Heritage.

5. Convenience and Cost: Where you live, On the go lifestyle, Family income

6. Advertising: Health messages, Influence your looks.

THE NURSE

Participates in initiatives focused on prevention of health problems Educates clients about the benefits of nutritional dietsAdvocates for the nutritional needs of clients Develops nutritionally balanced diet plans for clients

Types of Nutrients1- MacronutrientsCarbohydrates, proteins and fats are called macronutrients, because they're large, and energy nutrients because they provide the fuel your body needs to do things.2- MicronutrientsThese include Vitamins and minerals.They are called micronutrients because they're much smaller in comparison. That doesn't mean they're less important; they're still essential nutrients, but we only need small amounts.

Macronutrients•Carbohydrates•Proteins•Fats

Carbohydrates

Carbohydrates: are the starches and sugars present in food.Polysaccharide are obtained in:-

•whole grains •seeds•Legumes

They are classified as either simple or complex.

Simple carbohydrates:Are sugars.

•Glucose , fructose and glactose.

Disaccharides

Composed of two monosaccharides

Broken down into the two monosaccharides before being absorbed by the body

Sucrose

Lactose

Maltose

Three Most Common Disaccharides

Complex carbohydrates

Polysaccharides :-

Starches

Glycogen

Celluloses

Fibers

Starches

The storage form of energy in plantsFound in two forms:

amyloseamylopectin

Glycogen

Form in which starch is stored in the liver and muscles

Accessed when glucose levels fall too low

Fiberis an indigestible complex carbohydrate that helps move waste through the digestive system.• Body converts all carbohydrates to glucose (simple sugar).

Glucose is:- Preferred fuel source for:

red blood cells

the brain

the central nervous system

Two categories of fiber:

insoluble and soluble

Insoluble fiber:

includes cellulose, hemicelluloses, and lignins

gives plant food texture

adds bulk to stool and promotes laxation

Cellulose:

the most abundant polysaccharide in nature

contains the monosaccharide glucose

a rigid fiber that provides structure to plants

Soluble Fiber

Includes gums, pectins, some hemicelluloses, and mucilages

Slows digestion, diminishing how quickly sugar is absorbed in the intestine

Binds fatty acids in the intestine, resulting in lower blood cholesterol

2- ProteinsProteins are nutrients that help build and maintain body cells and tissues.•Proteins have many functions:

- Help make new cells.-Help make and repair tissues.- Help make enzymes, hormones, and

antibodies.- Provide energy.

Proteins are classified into two groups: complete and incomplete.Complete proteins :-contain amounts of all nine essential amino acids.SOURCES INCLUDE:

Fish, meat, poultry, eggs, milk, cheese, yogurt, and many soybean products.

Incomplete proteins :-lack one or more essential amino acids.SOURCES INCLUDE:

Beans, peas, nuts, and whole grains.

Foods high in protein use the most energy to digest the protein, synthesize amino acids, and metabolize protein into urea and glucose. Alcohol uses the next most amount of energy, followed by the carbohydrates, such as in fruits and vegetables. The overall contribution of these differences to total energy expenditure is minimal.

3- FatsA compound that is insoluble in water, but

soluble in an organic solvent (e.g., ether, benzene, acetone, chloroform)

• “lipid” is synonymous with “fat”, but also includes phospholipids, sterols, etc.

• Chemical structure: glycerol + fatty acids

•The building blocks of fats are called fatty acids.

•Saturated:•Animal fats and tropical oils•High intake is associated with an increased risk of heart disease

•Unsaturated:•Vegetable fats•Associated with a reduced risk of heart disease

•Fatty acids that the body needs, but is unable to make are called essential fatty acids

•Fatty Acids are classified as two types•Saturated and unsaturated

Polyunsaturated Fats

The polyunsaturated fats (omega-6 fatty acids and omega-3 fatty acids) are essential because the human body doesn't have enzymes to produce them.Omega-6 fatty acids are found in vegetable oils and are rarely deficient (and more commonly people consume too much).Omega-3 fatty acids are not as common and are more likely to be deficient, but we can find omega-3's in foods like fish and seafood, soy,

walnuts and foods fortified with omega-3 fats.

Functions of Fats•Transport vitamins A, D, E, and K.•Sources of linoleic acid- essential fatty acid that is needed for growth and healthy skin.•High intake of saturated fats is linked to increased cholesterol production. •Excess cholesterol can lead to an increased risk of heart disease.

2- MicronutrientsVitamins and MineralsVitamins are compounds that help regulate many vital body processes that include:1.Digestion 2. Absorption 3. Metabolism 4. Circulation

Vitamins are classified into two groups:a- Water-soluble Vitaminsb- Fat-soluble Vitamins

b- Fat-soluble vitaminsAre absorbed, stored, and transported in fat. Your body stores these vitamins in your fatty tissue, liver, and kidneys. Excess buildup can be toxic. These include vitamins A, D, E, and K.

a- Water-soluble vitamins:Dissolve in water and pass easily into the blood during digestion. The body does not store these so they need to be replenished regularly. Includes vitamins C, B1 ,B2, Niacin, B6, Folic acid, and B12.

Minerals

Minerals are substances that the body cannot manufacture but are needed for forming healthy bones and teeth and regulating many vital body processes.Important minerals include:Calcium -Phosphorus –Magnesium -Iron

Characteristics:

inorganic elements

can combine with other compounds or elements

not a source of energy

Functions:

providing structure

maintaining fluid balance

serving as cofactors and coenzymes

role in nerve transmission and muscle contraction

acting as reserves

Mineral balance

Poor mineral status causes:

1/ Insufficient intake

2/ Mineral interactions

3/ Lowered mineral absorption

4/ Increased mineral excretionBody adjustment of absorption and excretion for balance

Mineral toxicity:-result of excess mineral content:

1/ Increased intake2/ Altered metabolism3/ Environmental exposure

Mineral bioavailability

Affected By:

1/ Naturally occurring substances

2/ Interactions among minerals

CALCIUM

Health and disease prevention:

strong bones and teeth

effect on biological reactions

potential to lower risk of chronic diseaseLow levels of calcium:

altered calcium balance

diminished bone mass

varies based on age

nurse should stress adequate intake

medical conditions may affect intake requirements

Dietary Reference Intakes (DRI)

Calcium Deficiency

Hypocalcemia:

pancreatitis, certain cancers, and severe vitamin D deficiency

may affect muscle contraction and nerve conduction

Poor mineral bone density:

osteoporosis

adequate intake of calcium and vitamin D

PHOSPHOROUS

Majority exists in bone:

structural component

reservoir for maintenanceBody seeks to maintain steady stateRDA is 700 mg/day for adultsRole in wellness:

affects bone health

Protein-rich foods

Phosphate Deficiency

Hypophosphatemia:

rare

can lead to anorexia, muscle weakness, confusion, alteration in blood clotting, and immune dysfunction

severe cases can lead to respiration and cardiac function problems

Magnesium

Bone and soft tissue

Kidney responsible for homeostasis

Role of magnesium:

metabolic enzyme reactions

maintenance of heart rhythm

regulation of sodium, potassium, and calcium homeostasis

DRI varies based on age

risk for patients with poor kidney function

positive effects of a diet with appropriate magnesium

low intake brings risk of metabolic syndrome

Best sources:leafy vegetableswhole grainsseedsnuts

Magnesium Deficiency

Neuromuscular hyperexcitability:

can lead to cardiac arrhythmias and muscular contractions

Hypokalemia, hypocalcemia, and increased intracellular calcium

Magnesium not generally assessed in routine testing

Cardiac patients on diuretic therapy are at risk

Electrolytes

Sodium, Potassium, Chloride

Effects:

fluid concentration

acid-base balance

nerve conduction

membrane permeability

Body seeks to maintain balance

DRI:

sodium for adults age 19 to 50 years is 1.5 gm per day

chloride for adults age 19 to 50 years is 2.3 gm per day

Sodium’s relationship to blood pressure

Potassium

Found within cells and in extracellular fluids

Involved in:

neural transmission

muscle contraction

maintenance of fluid balance

DRI:

for all adults, the AI is 4.7 gm /day

Major sources:fruitsvegetableslegumesmilk

Potassium

Trace Minerals

Present in the body in amounts less than 5 grams

Daily requirement is less than 100 mg

Some necessary, others not

Iron

Essential for oxygen transport

Body conserves iron stores

Iron needs change over lifespan

Iron consumption concerns:

excess iron

hemochromatosis

iron deficiency anemia

iron supplements

Heme iron:

animal foods

better absorbed

Nonheme iron:

plant foods

not absorbed as well

primary dietary source of iron

Iron

Major sources

Zinc Roles:

cofactor or coenzyme for catalytic reactions

enzyme structure and regulation

involved in DNA expression, cell growth, differentiation

Homeostasis—GI tract

Recommendation:

adult females 8 mg daily

adult males 11 mg daily

Common sources:

oysters

red meats

other seafood

wheat germ

wheat bran

fortified breakfast cereals

Zinc

Selenium

AntioxidantSoil contentRDA: 55 mcg

Copper

Requirements uncertain

Constituent of enzymesWound healingRDA: 900 mcg daily

Sources:plants grown in soil with high selenium contentbeef, poultry, seafood, and nuts

Sources:organ meats, seafood, and nutsgrain proteins

Fluoride

Mineralization of bone and teethDRI:

2 mg per day for adult females 3 mg for adult malesPresent in drinking water

Iodine

Present in Soil and Seafood

Hormones thyroxine and triiodothyronineRDA: 150 mcg for adults

Water

Water helps to maintain many bodily functions.•Lubricates your joints and mucous membranes.•Enables you to swallow and digest foods. •Absorb other nutrients, and eliminate wastes.•Perspiration helps maintain normal body temperature.•Water makes up around 65% of the body.•It’s important to drink at least 2 liters (8 cups) of water a day to maintain health.

The Food Guide Pyramid

Nutrition and Product LabelingProduct labeling advertise a food’s nutritious value.*Some common used terms are light, less, free, more, rich, rich in, lean, or excellent source of. *Many food products have open dates on their label.Examples:*Expiration date.*Freshness date.*Pack date and*Sell-by date.

Food Sensitivity and Foodborne Illness1. Food Allergy:-A condition in which the body’s immune system

reacts to substances in some foods.•Allergies to peanuts, tree nuts, eggs, wheat, soy, fish, and shellfish. •A simple blood test can indicate whether a person is allergic to a specific food. •These reactions may include rash, hives, or itchiness of the skin; vomiting, diarrhea or abdominal pain; or itchy eyes and sneezing.

2. Food Intolerance:A negative reaction to a food or part of a food caused by a metabolic problem.

•The inability to digest parts of certain foods or food components.•May be associated with certain foods such as milk or wheat, or even with some food additives.•Common symptoms include nausea, vomiting, diarrhea, and fever.

3. Foodborne Illness:A term that means a person has food

poisoning. •To prevent foodborne illness you should clean, separate, cook and chill food when handling it.•A foodborne illness can result from eating foods contaminated with pathogens or poisonous chemicals.