Nutrition and Health

Nutrition Status

YOU ARE WHAT YOU EAT??? True to an extent – there is a link between food,

nutrition and health

Nutrition status of an individual may be measured in a number of different ways. Clinical evaluation – shiny hair, bright eyes Assessment of dietary intake – (RDI) Laboratory Test - blood

Nutrition Status Cont….

To assess the nutrition status of an entire nation in this way is time consuming and expensive. Methods used:

Census data Morbidity and Mortality rates Food Consumption surveys Nutrition surveys

Clinical Evaluation

Refers to the observation of the physical signs.

Fig 2.1 – indicates some of the physical signs of good nutrition.

Bright eyes Shiny Hair Clear Complexion

Recommended Dietary Intakes (RDI)

RDI – set in 1954, revised in 1991. The levels of intake of essential nutrients

considered, on the basis of available scientific knowledge, to be adequate to meet the known nutritional needs of practically all healthy people. (Appendix A)

NHMRC – recommends the following uses of the RDI’s

As a guide for planning menu’s for individual or groups For an assessment of an adequacy of the diet As a denominator for nutrition labeling Reference for monitoring the availability of nutrients in the national

food supply Guide in planning diets for specific therapeutic purposes

Body Mass Index (BMI)

Measurement of the human body can also indicate the nutrition status of an individual.

Measures the amount of body fat a person carries. BMI = weight (kg)

height 2 (m)

Below 18 – very underweight Under 20 – underweight 20-25 – acceptable 25-30 – overweight 30 and over – Obese

ACTIVITY 2.1

Laboratory Test

Tests are often used in conjunction with clinical evaluations.

Blood and Urine tests are the commonly used test

Food Consumption Surveys

The ABS provides data on the food available for consumption

Apparent food consumption data can indicate the type of nutritional problem you might expect in different countries.

Nutrition Surveys

Surveys gather information about what people eat & the nutrient content of the food intake.

ACTIVITY 2.2 Review 1-5

Food, Nutrition & Health

Food and the human body are composed of the same materials Carbohydrates Lipids (fat) Protein Water Vitamins Minerals

Nutrients

Nutrients – Organic and inorganic substances found in food that are required by the body for the growth and maintenance of body systems.

Macronutrients – required by the body in large amounts.

Micronutrients – required by the body in small amounts.

Nutrients cont…

Cells are the basic living unit of your body. Cells use nutrients to perform functions such as energy production, growth, repair and regulation of body processes.

Consumption of a variety of foods ensures a balance of nutrients to meet the body’s needs.

Digestion of nutrients

Digestion is the mechanical breakdown and mixing of food, the movement of food through the digestive tract and the breakdown of food through the action of enzymes.

Enzymes are a protein based chemical that allows the chemical reactions involved in digestion to take place.

Absorption

Some substances, such as water-soluble vitamins, alcohol, salts and glucose may be absorbed directly from the stomach.

Most absorptions occur in the small intestines – contains villi.

Large intestines – absorbs mostly water

Metabolism

Metabolism refers to all the chemical reactions involving nutrients that occur in the body.

Catabolism refers to the chemical reactions that result in the breakdown of molecules into simple form

Anabolism refers to the chemical reactions that result in new molecules being built.

Basal Metabolism refers to the use of energy in the body

REVIEW 1-6

Macronutrients

Carbohydrates

Proteins

Lipids/Fats

Carbohydrates

Preferred source of energy for the body. Two types are:

*Complex Carbohydrates (starches)– Occur naturally in vegetables and grains

*Simple Carbohydrates (sugars)– fruit, honey and milk

Both types are broken down into glucose during digestion providing energy for your body.

Carbohydrates cont….

Provides 16 kilojoules (energy) per gram. Some good food sources of carbohydrates are

bread, cereals, pasta, rice, potatoes and bananas. Fibre – A type of complex carbohydrate that the

body does not digest. Necessary for the transport of food in the intestinal tract, providing bulk to assist in the removal of waste from the body. Examples of fibre rich foods are wholegrain and wholemeal bread and cereals, fruit and vegetables.

ACTIVITY 2.3 & 2.4

Lipids/Fats

Concentrated source of energy. Difficult for the body to break down to use for energy. Provide 37 kilojoules (energy) per gram.

Fats contain fat soluble vitamins (A & D) and essential fatty acids

Provide insulation and protection for the body. Food sources are cream, meat, whole milk,

vegetable oils, oily fish. Cholesterol – A type of fat crucial to metabolic

functions. ACTIVITY 2.5

Proteins

Required for growth, repair and maintenance of body cells and tissues. Example – production of enzymes and hormones.

Two types are:* Complete Proteins – 8 essential amino acids found in

foods such as meats, poultry, eggs and milk.* Incomplete Proteins – Lacks certain amino acids and

is found in plant foods such as nuts, legumes and beans.

Secondary source of energy providing 17 kilojoules (energy) per gram.

Water

Water is essential for life. Every body function requires water – transports nutrients to cells, filters out waste and lubricates food as it moves through the gastro-intestinal tract.

Many fruits and vegetables have high levels of water.

ACTIVITY 2.6 REVIEW 1-8

Micronutrients - Vitamins

Required by the body in small amounts. They help the body to use energy effectively and regulate the action of chemicals in the body.

Two types:• Water soluble – C and B group vitamins• Fat soluble – A, D, E and K.

Water Soluble Vitamins

Vitamin C – Needed for soft tissue formation and healing. Aids iron absorption. Food sources include citrus fruits and leafy green vegetables.

B group vitamins – B1, B2, B3, B6. Enable energy to be released from macro-nutrients. Food sources include lean pork, wholegrain bread and cereals.

B group vitamin – B12. Necessary for blood cell formation and maturation. Food sources include liver, meat, milk, eggs and cheese.

Fat-Soluble Vitamins

Vitamin A – Maintenance of normal vision, growth of soft tissues and bone formation. Food sources include butter, cheese, yellow fruits and leafy green vegetables.

Vitamin D – Assists calcium and phosphorus absorption from the intestine. Sunlight is the major source.

Vitamin E – Anti-oxidant that prevents damage to cell membranes. Food sources include vegetable oils, eggs and green leafy vegetables.

Micronutrients - Minerals Inorganic chemical elements in the diet. The human

body needs at least 20 different minerals to function properly.

The main minerals are: Calcium• Phosphorus• Iron• Sodium• Fluorine• Iodine

Use the information on page 80 of your text to find out the major food sources and functions.

ACTIVITY 2.7 & 2.9 & 2.10REVIEW 1-13 H/W

Nutrition and disease

The amount of food that we eat is not the issue. It’s the quantity of nutrients.

Foods high in saturated fat to be avoided and kept to a minimum

Fruits and vegetables are to be encouraged

Cardiovascular disease

Cardiovascular disease refers to disease of the HEART & BLOOD VESSELS.

Leading cause of death in Australia The main diseases that relate to diet in this

category include: Coronary Heart Disease (Heart Attack,

angina) Hypertension Stroke

Cardiovascular disease cont…

The underlying cause of CVD is atherosclerosis, which is hardening of the arteries.

Atherosclerosis occurs when plaque builds up along the walls of the blood vessels. Cholesterol is a major component of plaque.

As the problem progresses, arteries become narrower and less elastic and blood flow become restricted, usually increasing blood pressure.

SEE FIG 2.16

Cardiovascular disease cont…

Coronary Heart Disease (ishaemic HD) Caused by a clot or other obstruction Heart Attack occurs when a clot lodges in one of

the coronary arteries and blocks the supply of blood (O2) to the heart.

Angina Caused by atherosclerosis. Pain caused by an inadequate blood supply Happens when the heart is working harder –

during exercise – Angina is a warning that the heart muscle is at risk

Cardiovascular disease cont…

Risk Factors Age Gender Heredity Hypertension –Uncontrolled high blood pressure

can overload the heart Smoking Stress Obesity Nutrition

Cardiovascular disease cont…

Relationship to diet The nutrients that contribute to arthrosclerosis

will also contribute to coronary HD. CHOLESTEROL SATURATED FAT FIBRE SODIUM

(Summarise the above)ACTIVITY 2.11 & 2.12

Cardiovascular disease cont…

Hypertension Hypertension is also known as high blood pressure Refers to the pressure of the blood on the walls of the

blood vessels. The factors that contribute to the pressure inside the blood vessels include:

Pumping from the heart Resistance from the capillary itself Volume of fluid

When blood pressure becomes too high smaller blood vessels become damaged, kidneys may become damaged. Most people don’t know that they have it

Cardiovascular disease cont…

Risk Factors Age Heredity Obesity Alcohol – people who tend to drink more then two

standard drinks a day Smoking

Relationship to diet Sodium Moderate intake of alcohol

Cardiovascular disease cont…

Stroke A Stroke occurs when a blood clot lodges in an

artery in the brain, blocking oxygen supply and permanently damaging the brain tissue surrounding the blockage. The problem depends on the part of the brain that is affected.

Risk Factor Hypertension Smoking Atherosclerosis

Relationship to diet Same as Atherosclerosis

Obesity

A person who is overweight is a least 10% heavier then they should be for their height.

A person who is obese is a least 20% heavier then they should be for their height.

Increase the risk of CVD a number of other problems

Cause Lifestyle Heredity Hormones

ACTIVTY 2.13 & 2.14

Diabetes mellitus

Diabetes mellitus is a conditions where the pancreas produces inadequate or ineffective insulin. This means that the body is unable to process carbohydrates normally.

Three of the more common forms of diabetes include:

Type 1 – juvenile diabetes, which usually begins in childhood

Type 2 – mature onset diabetes, which is usually begins in adulthood

Gestational – appears in the mother during pregnancy and disappears soon after birth

Diabetes mellitus cont…

Risk Factors Age: type 2 affects people over age of 40 Heredity Obesity – See Fig 2.20 pg 96 Diet

Relationship to diet Carbohydrates Alcohol Fat

ACTIVITY 2.15

Anaemia

Iron deficiency is the most common nutritional deficiency disease in Australia

Most at risk – female youths and pre-menopausal women.

Risk Factors Gender Pregnancy Diet

Relationship to Diet Vitamin C – promotes iron absorption Vitamin B – foliate is responsible for the production of red

blood cells

Dental Caries

Dental Caries (tooth decay) results from the build up of plaque on the tooth surface.

The bacteria that form the plaque break down sugar in the foods and product acids as a by product. It is those acids that attack teeth and create holes in the enamel.

Risk Factors Sugar Type of foods Fluoride Dental Care

Relationship to diet

Osteoporosis

Osteoporosis is the condition that results when calcium is lost from the bones leaving them porous and weak.

This deterioration increases the risk of a fracture from relatively minor injuries.

Risk Factors Diet Gender Hormones Genetics Smoking

Osteoporosis cont…

Relationship to diet Calcium Phosphrous Vitamin D

Colorectal Cancer

Colorectal Cancer - Second most commonly diagnosed cancer in Australia – 1st is skin cancer

Develops from polyps (small growth) that form on the lining of the bowel. Polyps are usually harmless but can develop into cancerous tumors.

Risk Factors Genetics Age Diet Physical Inactivity

Colorectal Cancer cont…

Relationship to diet Fibre from vegetables seem to play a protective

role against colorectal cancer Cabbage Broccoli Brussel sprouts Cauliflower

It is thought that these vegetables induce anti-cancer enzymes and block the substance in action of carcinogens (substance that promotes cancer)

ACTIVITY 2.18 & 2.20 Review 1- 19 H/W

Consequences of dietary imbalance

Consequences for the community of dietary imbalance go far beyond the disease itself.

The costs associated with dietary imbalance can be divided into three types

Direct Cost Indirect Cost Intangible Cost

Direct Cost

Direct Costs include those associated with providing health services to individuals and their families:

Diagnosis Treatment Hospital care

Further divided into the following: Pharmaceutical

Both prescriptions and non prescription medications used to treat ill health.

Direct Cost cont…

Medical Consultations Doctors and Specialists

Hospital Cost of accommodations, treatment, pharmaceutical

cost while in hospital, emergency rooms, outpatient activities and general hospital operating costs

Allied Health Treatment Physiotherapists, Chiropractors, homeopaths and

dieticians Ambulance

Indirect Costs Indirect Costs are not directly related to the disease.

Indirect costs may be borne by the individual or by the community. They include: Absenteeism

Cost to the economy of people who are unable to work because of the disease they have themselves or a dependent.

Lost of Productivity Person unable to work to their full capacity – who is

suffering from a disease Lost of earnings

Amount a person would usually earn it they did not suffer a disease.

Home Help Help around the home. E.g. meals on wheels

Intangible Cost

Intangible costs are sometimes hard to identify but are probably best described as the social and emotional costs. These include

Pain Suffering Anxiety Reduced quality of life

Very hard to assign a dollar value to these costs buy they are often the costs that are felt the most

ACTIVITY 2.21 & 2.22

The Role of nutrition in public health

Given the costs involved in ill health across Australia, it is in everyone’s best interest to increase the health status of all Australian’s.

Public health aims to do this through nutrition policies and programs.

Australian Guide to Healthy EatingDietary Guidelines across the lifespanVarious campaigns run by non-

government agencies