Transcript Human nutrition and health - Mr Hartan`s Science Class

SPECIAL TOPICS IN HUMAN
NUTRITION AND HEALTH
(YOU ARE WHAT YOU EAT)
 Nutrients: Chemical substances (biomolecules) found in foods and used by
the body for growth and energy. Every cell in your body requires
nutrients in order to function properly.
 Types of Nutrients: Carbs, Proteins, Lipids, Nucleic Acids, Vitamins, &
Minerals
 Deficiency: A person is not getting enough of a certain nutrient, resulting
in a health problem.
Type of
Compound:
Minerals
Vitamins
Inorganic
Organic (Contain Carbon)
Source:
Rocks, Soil, Sea Water
Synthesized by plants and animals.
Examples:
Sodium Ion: (Na+)
Calcium Ion: (Ca2+)
Iron Ion: (Fe2+)
Vitamin A: C20H30O
Vitamin C: C6H8O6
Vitamin D: C27H44O)
Function(s):
Help in bone and tooth
formation, blood coagulation,
and muscle contraction.
Are important in energy metabolism, as coenzymes,
blood clotting, maintaining healthy skin, eyes and
hair.
Vitamins and Minerals are required by the body in small quantities. Vitamins are structurally
different than minerals.
“Nutrients are chemical substances found in foods and used in the
human body for growth and energy.”
Essential Nutrients
Non-Essential Nutrients
Cannot be replaced or synthesized by
the body and, therefore, required by
the diet.
Not necessary in the diet because these
nutrients can be synthesized by the
body.
Dietary fiber is required for a healthy diet but is not absorbed by the body and,
therefore, not necessarily considered a nutrient.
READING & REVISING THE NUTRITION LABEL
Reading a Nutrition Label
TOP 30 WORST FOODS
IN AMERICA
Recommended Daily Allowance
kcal requirements are recommendations. Requirements
can vary depending on size, gender, activity levels, health.
Health Consequences of Diets Rich in
Carbohydrates
• Consumption of large amounts of sugar can increase the risk
of obesity, Type II diabetes and tooth decay.
• Consumption of large amounts of starch can cause obesity –
slow digestible starches, however, can prevent rapid changes
in blood glucose levels.
• Consumption of indigestible fibers in vegetables and fruits can
lead to a feeling of satiety, slow glucose absorption, lower
risks of certain types of colon cancers and
Is Sugar Toxic?
What Happens When Your Diet is
Deficient in Certain Nutrients?
Protein Deficiency (Example: Kwashiorkor)
• Kwashiorkor is a disease resulting from malnutrition.
• Certain essential amino acids are lacking in the diet
due to extremely low protein intake.
• Kwashiorkor is common among children in nonindustrialized nations (the name comes from Ghana,
a West African Country).
“The disease of the first child, when the second child is
born”
Kwashiorkor is easily treated by providing the
individual with sources of food high in protein (eggs,
high-protein biscuits, etc.)
Kwashiorkor (Symptoms)
Kwashiorkor (Symptoms):
Artificial Dietary Supplementation: Iodine
Although Iodine is present in seawater and, therefore, fish &
kelp, individuals without access to regular seafood are at risk for
not getting enough iodine.
Iodine is a component of the hormone thyroxin (produced by the
thyroid gland in the neck). Hormones made by the thyroid gland
regulate the growth at which energy is released by the body.
Insufficient Iodine In the Diet Can Result In:
Goiter: An inflammation/swelling in the neck.
Cretinism in babies born to mothers with an iodine deficiency.
Cretinism results in stunted growth and varying degrees of
mental problems.
Goiter & Cretinism
Vitamin/Supplement Benefits?
Consequences of Excess Fat Consumption
Consumption of fats in large quantities carries a significant risk of:
1. Obesity
2. Elevated cholesterol levels.
3. An increased risk of coronary heart/artery disease (positive
correlation).
Not all fats are created equal.
• Polyunsaturated and monounsaturated fats are healthier than
either trans fats and saturated fats.
• Trans fats carry the greatest risks to human health.
What is Atherosclerosis?
The Benefits of Reducing Cholesterol (LDL)
Cholesterol is an essential component (lipid) of the human body. It is
considered a steroid and often is the basis for various hormones and cell
membranes.
• There are two main types of cholesterol (HDL vs. LDL). High LDL (low-density
lipoproteins) levels are associated with increased risk coronary heart disease.
Research has shown that a 10% rise in blood cholesterol plasma levels is
associated with a 30% increase in the risk of death from CHD. It appears as
though total blood cholesterol levels are less important the LDL levels.
• Diets that are high in saturated are linked (positively correlated) with high LDL
and total blood cholesterol levels, along with CHD.
• Cholesterol levels do have a genetic component and high cholesterol levels
tend to run in families.
• High LDL levels promote inflammation and plaques.
Reducing saturated fat consumption and high animal product consumption is a
first step in lowering cholesterol. Diet and exercise are critical. Medications may
be necessary.
Cholesterol
Coronary Artery Disease
Angioplasty
Videos
Interactive World
Hunger Map
Obesity in the U.S. (A Preventable Condition)
(Abnormal or excessive fat accumulation that may impair health)
Key Facts: Source (http://win.niddk.nih.gov/statistics/)
• Approximately 68.8% of adults are considered overweight or obese.
• Approximately 35.7% of adults are considered to be obese.
• Approximately 6.3% have extreme obesity.
• Almost 74% of men are considered to be overweight or obese.
• The prevalence of obesity is similar for both men and women (about
36%).
• About 8% of women are considered to have extreme obesity.
• Since the early 1960s, the prevalence of obesity among adults more than
doubled for adults >20. (From 13.4% to 35.7%).
• Among children and adolescents, the prevalence of obesity also
increased during the 1980s and 1990s but has leveled off at 17%.
 A BMI greater than or equal to 25 is considered overweight.
 A BMI greater than or equal to 30 is considered obese.
Just the Facts
Causes of Obesity and Overweight
The fundamental cause of obesity and overweight is an energy imbalance
between calories consumed and calories expended.
Globally there has been:
• Increased intake of energy-dense foods high in fat and sugar and the
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availability of cheap, highly-processed foods (as compared to relatively
expensive fruits and vegetables).
An increase in physical inactivity due to the increasingly sedentary nature
of many forms of work, changing modes of transportation, and increasing
urbanization.
Cheaper foods have allowed for LARGER portion sizes.
Many tasks that were done in the home by hand are now done by machine.
Popular activities require less activity (tv and video games have replaced
sports).
Health Consequences of Overweight and
Obesity
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Overweight and obesity are the fifth leading risk for global deaths.
Approximately 2.8 million people worldwide die each year as a result of
being overweight or obese.
44% of the diabetes burden, 23% of the ischemic attack heart disease
burden and between 7% and 41% of certain cancer burdens are
attributable to overweight and obesity.
Health Consequences
Adverse metabolic effects on blood pressure, cholesterol, triglycerides, and
insulin resistance.
Risks of coronary heart disease, ischemic stroke and type 2 diabetes
mellitus increase steadily with increasing BMI.
Increased risk of cancer of the breast, colon, prostate, endometrium,
kidney and gall bladder.
Increased risk of musculoskeletal disorders (osteoarthritis)
Treatment Options
• Increased physical activity.
• Diet counseling and diet modification to include more fruits and
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vegetables.
Psychological counseling.
Support Group Participation.
Surgery: Gastric Bypass Surgery, Liposuction, Apronectomy
Medications (Orlistat)
Interactive Graphic
(Worldwide Obesity Rates)
Obesity (Videos)
Body Mass Index (BMI)
An imperfect scientific attempt to quantify whether or not an individual has
the appropriate mass.
WHO: “Body mass index (BMI) is a simple index of weight-for-height that is
commonly used to clarify overweight and obesity in adults. It is defined as
a person’s weight in kilograms divided by the square his/her height in
meters (kg/m2).”
BMI = (mass in kg)/(height in m)2
Reminder(s):
• Weight (Newtons) is a measure of the force pulling you down towards the
ground.
• Mass (kg) is the amount of matter you have in your body.
Example
Example: What is the BMI of a 17 year old woman who
is 1.65 m tall and has a mass of 60 kg?
BMI = (mass in kg)/(height in m)2
BMI can not indicate how mass is distributed.
BMI
Status
Below 18.5
Underweight
18.5-24.9
Normal Weight
25.0-29.9
Overweight
30.0 and Above
Obese
Type II Diabetes
Type II diabetes is the most common form of diabetes worldwide and
develops as a result of the complex interplay between genetics and
diet.
(Also known as ‘adult-onset diabetes’ or diabetes mellitus type II or noninsulin dependent diabetes mellitus (NIDDM)).
• Type II diabetes results from the body developing an insensitivity to insulin
over a period of years. While it is most common in overweight or obese
adults over age of 40, it is now being observed in overweight children.
• Some groups have a higher incidence of Type II diabetes than others: (1)
Native Australians (Aborigines); (2) Native Americans; and (3) Maoris.
Type II Diabetes
(Animations)
Reminder: Beta cells in the pancreas produce insulin while
Alpha cells produce glucagon.
Statistics and Symptoms
(can be mild and develop over a period of years)
Symptoms: (1) being more thirsty than usual; (2) urinating
more than usual; (3) feeling tired and fatigued all the time; (4)
more infections than usual (skin infections in particular); (5)
elevated blood glucose levels and glucose in the urine.
Dietary Advice for Type II Diabetics
(gaining Control of blood Glucose levels)
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5.
Decreasing body mass and maintaining a healthy BMI through
exercise and a proper, well-balanced diet.
Eating foods rich in fiber and complex carbs, cutting down on
saturated fat. Complex carbs release their energy slowly. Fiber
allows nutrients to be absorbed slowly over time.
Eating small, regular meals throughout the day.
Eat lots of fresh fruits and vegetables. Low GI foods.
Exercise.
The Ethical Issues of Meat Consumption
Many people choose what to eat, based on likes and dislikes,
availability, choice and cost. Some people also have ethical reasons
for not eating certain foods.
• Vegetarians do not eat the flesh of any animals: no red meat, no poultry,
and no fish.
• Some vegetarians (vegans) do not eat ANY animal products (eggs, milk,
dairy, honey) or any product that contains animal products.
For some vegetarians and vegans, vegetarianism goes even further . . .
They will not wear/use leather, fur, wool or silk.
The Stats & Shocking Facts
Documentaries/Lectures
Warning: Some of these videos are Graphic/Disturbing