Nutrition 2

NutrientsMacronutrients

Carbohydrates Proteins Fats

All organic molecules

Water

Micronutrients

13 Vitamins All organic molecules

15 Minerals Elements, inorganic

Essential Nutrients

Nutrients the body cannot make, or produce in sufficient quantity

essential nutrients “Essential” means “required in the

diet”

Nonessential nutrients

Nutrients manufactured by the body from things in the diet are nonessential

Cholesterol, creatine, and glucose are examples

Nonessential nutrients are present in food, but not required in our diet

Nutritional State of the U.S. and the World

Just seventy years ago vitamin deficiency diseases

were common in children and adults

Disease due to malnutrition became more common before and during the Great Depression

In the developing world, we still see these deficiency diseases.

Iron—most common deficiency

1/3 of people in world are iron deficient ---mostly women and children

People with iron deficiency are weak and tired have short attention span are more susceptible to infection

Vitamin A Deficiency

Common in the developing world, esp.South Asia, South-East Asia and Africa.

Mainly affects infants, young children and pregnant women.

the number one cause of preventable blindness in children

increases the risk of death in infants.

Fig. 1-9, p. 15

Pellagra- Lack of Niacin

Disease of “4 D’s,”

dermatitis diarrhea dementia

death

Fig. 2-2b, p. 3

Rickets: Calcium or Vitamin D deficiency

India: 42 percent of children under five are

underweight - 3,000 children

dying daily due to illnesses related to poor diets –

Girls are much more likely to die of starvation or illness.

Marasmus: Protein-Calorie Malnutrition

UNICEF

trains Niger

to battle

malnutrition

Nutrition and Health

Today

In the U.S.

Now, dietary excesses are the problem in the US

Majority of Americans die from cardiovascular disease or cancer

These account for 51% of all deaths

Also contributes to death from diabetes

Life Expectancy

Lifestyle Factors: 51% of influence on longevity

Diet is one of the most important lifestyle factors

related to disease development and prevention

diets are within our control

Agriculture

Domestication of plants and animals began about 12,000 years ago Exc: dogs, over 30,000 years ago

Most people lived on farms or in villages or migrated with herd animals

Industrial revolution began about 1760 Today, 51% of world’s population lives

in urban areas

Then and Now

Human survival mechanisms are no longer an asset Stimulating hunger in spite of excess body

fat Conserving the body’s sodium A preference for sweet-tasting food A digestive system that prefers high-fiber

diet All advantages for early humans

Modern life: we may love it, but it doesn’t love us

Today’s chronic health problems are from diets and lifestyles greatly different from our early ancestors

Human body functions best on low saturated fat, sugar, and sodium, lean sources of protein, high in fiber, complex carbohydrates, and vegetables and fruits

Life Expectancy 2004-2005

1. Andorra 83.5 years 2. Japan 82 Australia 80 Canada 80 Spain 79 White Americans 78.3 42. U. S. 77.1 Cuba 77.0 Mexico 76 African Americans 73.3

Healthy weight in adultsObesity in adultsOverweight or obesity in children and adolescentsGrowth retardation in children

Weight Status and Growth

US Nutrition Objectives

Fruit intakeVegetable intakeGrain product intakeSaturated fat intakeTotal fat intakeSodium intakeCalcium intake

Food and Nutrient Consumption

Schools, Worksites, and Nutrition Counseling

Meals and snacks at school (dev.)Worksite promotion of nutrition education and weight managementNutrition counseling for medical conditions

Food Security little or no change

Iron Deficiency and Anemia

Iron deficiency in young children and in females of childbearing ageAnemia in low-income pregnant femalesIron deficiency in pregnant females (dev.)

Improving Getting worse Little or no change Cannot assess (limited data)

DHHS

19-1. Healthy weight in adults

19-2. Obesity in adults

19-3. Overweight or obesity inchildren and adolescents

19-5. Fruit consumption

19-6. Vegetable consumption

19-7. Whole grain consumption

Highlighted Objectives

DHHS

Dietary Guidelines for Americans

A set of guidelines for healthy eating Provides practical suggestions for dietary changes Updated every five years

Healthy Eating Pyramid

For adults; Additional calcium for young women

We have to understand the science of nutrition so we can

make the right changes– and not waste our time, energy, and

money on the wrong changes!

Americans want Nutrition Information ButBut

Nutrition "information" does not have to be true to be reported to the public

Nutrition "information" ranges from sound to outrageous

Fraudulent nutrition information exists due largely to the pursuit of money

Reliable information generated by science

Science requires systematic study

Nutrition Information

Publicity in media may be truths, or half-truths and gossip

Publicity does not have to meet standard of truth

Opinions are protected by ‘Freedom of Speech’

But it’s illegal to put false or misleading information about a product on a product label, in a product insert, or in an advertisement

Nutrition Misinformation

• Common features of fraudulent information about nutritional products and services

• If you find these in promotional information, you should be very suspicious of the product or service

Qualified Nutrition Professionals

Registered, licensed, or certified dietitians (such as RD's) meet qualifications

established by the American Dietetic Association and state regulations

They are qualified to advise and instruct people in nutrition issues.

They, and many university professors, including many medical doctors, are usually trustworthy

Many MD's in private practice or authors of diet books are not!

Scientific Nutrition News

More than 8000 nutrition-related research articles are published each year

New results in these areas are hot topics: Obesity, Cancer, Cholesterol, Heart

disease, Vitamins, Food safety Media oversimplifies nutrition

stories

Sources of Nutrition Information

Reliable sources use the standards of proof required by science

These are based on multiple studies and arrived at by scientific consensus

Majority opinion of knowledgeable scientists

Nutrition recommendations are based on this consensus of scientific opinion

Science Gives Results

Sound nutrition information survives systematic examination as dictated by science

Science produces facts and evidence from laboratory, animal, and human studies

Scientific studies provide facts for developing public policies about nutrition and health

And for inclusion in textbooks about nutrition

Methods of Science

Specific methods employed vary depending on the type of research

Scientific studies are carefully planned First process is observation Next, is stating a question and

transforming it into an explicit hypothesis

Hypothesis is then proved or disproved by the research

Research Design based on answers to these

questions

What type of research design should be used?

Who should the research subjects be? How many subjects are needed in the study? What information needs to be collected? What are accurate ways to collect the

needed information? What statistical tests should be used to

analyze the findings?

Epidemiological Studies

May track how disease rates change as people change lifestyles

Typical are studies of Japanese immigrants to the US

Diet and disease differences

Japanese men’s health changes inrelation to dietary intake of carbohydratesand fats aftermoving to the USA

What Type of Research Design?

Epidemiological Studies Case-control Studies

Retrospective Studies Nutritional Survey Prospective Studies

Dietary Intervention Studies Clinical Trials

Randomized Clinical Trials

Clinical trials test the effects of a treatment or intervention

an experimental group a control group

Because of the “placebo effect” A double-blind procedure is used

when possible to eliminate bias

More Types of Studies

Literature Review

Meta-Analysis

“Other”

Science and Nutrition

Science is based on facts and evidence

Grounding ethic of scientists is that facts and evidence are more sacred than any other consideration

These characteristics of science and scientists are strong assets for the job of identifying truths

The End