Nutrition: Growth and Life SpanGrowth and Life Span

Copyright 2010:PEER.tamu.edu

Things to Consider:1.How do you feel about

your weight? …. Height?

3. Do you think you will always have the same weight or height relative to other students?

2. Have you and your siblings or friends grown in a uniform way over the years?

Factors That Influence Your Factors That Influence Your Growth Include:Growth Include:

Genetics Gender Nutrition Physical Activity Health ProblemsEnvironmentHormones

Which of these do you think are affecting you right now? Why?

Measures Used for Growth Differ In babies: length, weight, head circumference

In older children and teens: height, weight, body mass index

You can calculate how you compare with other people of your age.

Use the automatic calculator at:http://pediatrics.about.com/cs/usefultools/l/bl_kids_centils.htm

Or use activity included in lesson

Body Mass Index (BMI)For Adults:

• BMI is based on the ratio of your weight to your height

What BMI tells youBMI Categories for adults:

Underweight = <18.5 Normal weight = 18.5-24.9

Overweight = 25-29.9 Obesity = BMI of 30 or

greater

Body Mass Index

Comparisons for Children

Proper Nutrition is Crucial During Pregnancy and Early Childhood

If a woman is malnourished during pregnancy, or if her child is malnourished during the first

two years of life, the child's physical and mental growth and development will be impaired.

This cannot be made up when the child is older – it will

permanently affect the child.

Good Growth Requires Good Growth Requires a Balanced Dieta Balanced Diet

• Proteins: source of materials for growth and repair.• Carbohydrates: source of energy.• Fats: source of energy and contain fat soluble vitamins.• Vitamins: needed for many enzyme systems.• Minerals: needed for healthy teeth, bones, muscles etc.• Fiber: help your intestines function correctly; it is not

digested.

Protein – An Essential Nutrient for Growth

• A little protein chemistry:– Proteins are organic substances made of Carbon, Hydrogen,

Oxygen and Nitrogen.– Some proteins may also contain Sulfur or Iron.– Proteins are large molecules made up of combinations of amino

acids.

Enaptin: C44189H71252N12428O14007S321

See slide note on Enaptin’s function in the body

This is the general structure of an amino acid.The R stands for an organic subgroup.Proteins are chains of amino acids combined. They can get very large.Here is the chemical formula for Enaptin, a very large protein:

Protein – Most Essential for All Growth

All meats are high in All meats are high in protein!protein!

Protein content in grams per 1 cup:

Beef Sirloin 68.8Chicken Breast 43.3Salmon 40Cheddar Cheese 32.9Eggs 24.4Soybeans 22Almonds 20.2Beans, Pinto 15Peas, black-eyed 13Beans, red kidney 13Beans, baked 13Peas 8Spinach 6

Corn 5Rice 5Veggie burger 5Peanut butter 4Noodles 3.7Potatoes 3.5Beans, green 1.6Cauliflower 2Cabbage 1.5Carrots 1Cucumber 0.7Lettuce 0.7Mushrooms 0.3

Carbohydrates: Where we get Energy

• Some carbohydrate chemistry:– Carbohydrates are organic

substances made of Carbon, Hydrogen and Oxygen in a ratio of 1 carbon atom, 2 hydrogen atoms, and 1 oxygen atom (CH2O).

– Carbohydrates are also called “sugars” and “starches.”

– Carbohydrates are used in our bodies for energy.

– Foods high in carbohydrates include fruits, breads, pastas, beans, potatoes, bran, rice, and cereals.

Fats: the “Bad”…….• Fats are organic molecules

made of Carbon, Hydrogen, and Oxygen.

• Saturated fats are considered unhealthy for the body and have been linked to cardiovascular disease and several types of cancers.

• Examples of foods containing a high proportion of saturated fat include dairy products, animal fats and oils like coconut oil, cottonseed oil and palm kernel oil.

A double cheeseburger can have 35g of saturated fat! That is almost twice

the maximum daily amount suggested!

…And the “Good”• Unsaturated fats are fats in which

there is at least one double bond between the Carbon atoms. These fats, if used in place of others, can lower your risk of heart disease by reducing the total cholesterol and low-density lipoprotein (LDL) cholesterol levels in your blood.

• Sources of these fats include vegetable oils, fish, nuts, seeds, olive oil and avocados.

Learn more about fats here.

Compare the two types of fats. What is the difference?

Bones Need Key Components to Bones Need Key Components to Support GrowthSupport Growth

• Calcium• Vitamin D• Vitamin C• Exercise• Hormone release from

parathyroid gland

Did you know that sunlight induces skin cells to make vitamin D?

* See slide notes for information about HOW these components support bone growth.

Think Break:• What are some of the things that affect

growth rate?• Why is proper nutrition critical, even at a very

early age?• What are some good dietary sources of

protein, carbohydrates, and “good” fats?• Do you think your diet is balanced and

healthy?

Our Culture Affects our Diet

In Thailand, only 3% of the people have the ability to process (metabolize) milk sugar (lactose). Historically, these people have not been major consumers of dairy products. Why do you think this is?

In Northern India, where dairy foods have been extensively used in their culture for many centuries, about 70% of the people can metabolize lactose.Why do you think this is?

Examples:

Why do certain cultures seem to have certain food preferences?Japanese people eat large amounts of seafood.

Americans and Central Americans eat large amounts of corn.Argentineans eat large quantities of beef.

Large amounts of rice are consumed in Southern Asia.Why?

How Bones Grow: Longer Limbs and Taller Height

• Special tissue at ends of bones add calcium to underlying matrix of existing bone.

• The bone-forming tissue seals off somewhere around the late teens, and growth stops.

• Why do you think the growth stops?

• Researchers are currently trying to answer that question.

Pituitary Growth Hormone is Crucial for Cell and Tissue Growth

• Pituitary Growth Hormone is a protein made in pituitary

• Release controlled by neurons in the hypothalamus

• Stimulates liver and some other cells to make a growth factor

• Promotes protein build-up, reduces fat, and helps regulate blood glucose

•Some athletes illegally use Human Growth Hormone to stimulate more growth. This is a dangerous practice.

Links to Human Growth Hormone Information:AbuseInformation

Growth Hormone Use in Cattle• Growth hormone is regularly used by beef cattle

producers.• A small implant is inserted into the ear of the animal

and it slowly releases growth hormone over a period of around 120 days.

• Why do you think beef producers do this?*

*See slide notes for

more information.

Light Stimulates Cultured Bone

•Scientists have found that certain types of light promote cell growth.• Skin, bone and muscle cells grown in cultures were exposed to the same light-emitting diodes used to treat wounds in patients and grow plants in space.• Biologists found that cells exposed to the near-infrared light grew 150 to 200 percent faster than control cells not stimulated by the light. •Scientists are trying to learn more about the way cells convert light to energy and identify the wavelengths of light that are most effective at stimulating growth.

Growth at the Cell LevelGrowth at the Cell Level• Humans have about 100,000 billion cells (about 1 Humans have about 100,000 billion cells (about 1

billion/gram of tissue) – all came from a single billion/gram of tissue) – all came from a single fertilized egg cell.fertilized egg cell.

• In most tissues (except brain) huge numbers of cells In most tissues (except brain) huge numbers of cells die routinely and have to be replaced.die routinely and have to be replaced.

• Certain genes trigger the cycle of cell division.Certain genes trigger the cycle of cell division.• Certain types of cells, like skin cells and blood cells, Certain types of cells, like skin cells and blood cells,

divide frequently. Other cells, like kidney and heart divide frequently. Other cells, like kidney and heart cells, do not.cells, do not.

• Why do you think that is?Why do you think that is?

The Cell Cycle and Growth Factors Influence Growth

• Normal cells in most tissues divide, either to grow or replace dead cells.

• Specific proteins trigger growth of specific tissue.

• Examples: – Bone, blood, connective tissue, liver, skin– This is crucial for wound healing!!

Cancer is Growth That is Uncontrolled!Cancer is Growth That is Uncontrolled!

Characterized by cells that:Characterized by cells that:• Divide faster than they die. Divide faster than they die. Programmed cell death is called Programmed cell death is called apoptosis.apoptosis. It is a normal part of the It is a normal part of the cell cycle. Old or damaged cells die cell cycle. Old or damaged cells die and are replaced by new ones.and are replaced by new ones.

• Invade normal tissue and impair the Invade normal tissue and impair the function of the organ of origin.function of the organ of origin.

• Spread through blood, lymph, and Spread through blood, lymph, and body cavities to other organs.body cavities to other organs.

For more on apoptosis click here

Research with Cells and Tissue is Constantly Developing and Expanding:

Click on a Hyperlink Below to Learn More:

•Effects of space travel on cellular growth

• Use of stem cells for tissue regeneration

• Human tissue bank sources for transplants aid burnvictims, the visually impaired, the infertile, and persons living with cancer, heart defects, and various other illnesses and injuries.

•Tissue culture of a layer of pig intestine for growing human cells to help regenerate human tissue

Bone Marrow Stem Cells Cell Cultures in Space Pig Embryonic Stem Cell

Stem Cells and the Future

• Stem cells are found in all multicellular organisms.

• They have the ability divide and differentiate into many different cell types. That means they can make different types of body tissues.

• Stem cells can be embryonic stem cells or adult stem cells.

Adult Stem Cells from Bone Marrow

Potential Uses of Stem Cells

The stem cells could be grown in a culture and used to re-grow or repair tissues that are diseased or damaged.

Final thoughts-What do you think?

•Do you think your culture affects your food choices and overall health? How?

•How do you think the body “knows” when a cell needs to die? Discuss various options. How could knowing this be helpful in understanding cancer?

•The use of stem cells is a controversial topic.

• Why do you think this is?

•Injection of stem cells into a patient may not work. • Why do you think that is? (see slide notes for answer!)