FOOD

1. Provides energy for all of the body’s functions, from the beating of the heart & the elimination of wastes to the transmission of electrical & chemical signals in the nervous system. Food is the fuel that contains energy from the sun, originally captured & stored by green plants, then passed along to fruits, seeds, & animals. Humans eat these foods & burn the fuel they contain to release the stored solar energy. As long as we live, we have to eat and eat often!

Text from: Eating Well for Optimum Health Andrew Weil, MD

2. Food provides the building blocks of our bodies. In the same way that you can’t build a lego castle without lego pieces, you can’t build the parts of your body without certain nutrients.

The food we eat contain nutrients. Some of these we disassemble and then reassemble for parts we need. (Like breaking down the lego castle to build a lego ship instead.)

Some nutrients are essential because we can’t manufacture these on our own.

Macromolecules come in 4 types. All macromolecules are organic which means they are produced made by living things.

Carbohydrates

Lipids

Proteins

Nucleic acids

CARBOHYDRATES All carbs are made up of only 3 elements: Carbon, hydrogen, & oxygen.

All carbs look like this in their simplest form. By the way, this is called a simple sugar or monosaccharide.

mono = one saccharide = sugar

But remember I said that you can use these guys as building blocks. Well if you put a two of them together you get this. It’s called a disaccharide. Di = two

And if you string a bunch of monosaccharides together you get a polysaccharide. They look like this.

Luckily they have the same general shape (hexagonal) and they are all carbohydrates .

WHY ARE CARBOHYDRATES IMPORTANT?

They are the body’s preferred choice of

energy .

Just like your favorite shirt, you could wear the other shirt, but this one fits over your head without tugging.

WHAT FOODS CONTAIN CARBOHYDRATES?

Let’s review carbohydrates.

Why do you need to eat them?

What foods contain carbs?

List the 3 elements that are contained in carbohydrates.

Which of the following is a polysaccharide?

LIPIDS

Lipids contain 3 elements; carbon, hydrogen and oxygen.Sounds familiar right!

Fats are triglycerides which are solid at room temperature.

Oils are liquid at room temperature.

Why are lipids important to our bodies?

1. Storage of energy. This way if you run low on carbs…..

2. Thermal insulation.

3. Mechanical protection. Example surrounding delicate organs such as the heart.

4. Waterproofing. Like the wax in your ears.

Some fats are called phospholipids. They look like this.

Basically , the difference is that instead of 3 fatty acids and one glycerol, they have 2 fatty acids and a glycerol.

The also have an end that loves to be in water and a side that repels water.

Two layers together is a perfect way to surround a cell or a cell part!

Also, by the way, some hormones are lipids.

WHAT CAN YOU EAT TO MAKE SURE YOU HAVE LIPIDS?

Review time.

What 3 elements make up the group called lipids?

Which of these are a lipid? How can you tell?

List 3 ways your body uses lipids.

What foods contain lipids?

PROTEINS

Proteins are composed of 4 elements: carbon, hydrogen, oxygen and nitrogen. The basic unit is called an amino acid and it looks like this.

This is a 3-D image of a protein containing thousands of amino acids connected together & folded to make this distinct shape.

WHY DO YOU NEED TO EAT PROTEINS?

Proteins make up most of the structure of your body. Actually, by weight, you are mostly water with proteins in second place.

These are muscle cells.

This is someone with big muscles.

Proteins can be enzymes; these proteins regulate chemical reactions in your body.

Hair is also made up of protein.

Proteins also form some of the entrances and exits through the cell.

WHICH FOODS PROVIDE PROTEINS IN OUR DIET?

Review again? Of course!!!!

1. Which of the following suspects is a protein component?

2. List some foods that provide proteins?

3. How does my body use proteins?

NUCLEIC ACIDS

Nucleic acids make up DNA and RNA which are gigantic molecules that carry your hereditary information from generation to generation and are used to make proteins (remember them).

Nucleic acids are make up of lots of nucleotides (the smallest units) strung together. DNA takes the shape of a double helix.

We will learn a lot more about nucleic acids later!!!!

What is a condensation reaction?

• Reaction used to link monomers to build polymers by the removal of water.

• All macromolecules are built using this reaction!

Micronutrients are nutrients you need in small amounts. (That’s why they’re called micro.)

VITAMINS AND MINERALS

All natural vitamins are organic food substances found only in living things. With few exceptions, our bodies can’t manufacture them. Many enzymes depend on vitamins to work properly.

Minerals are inorganic substances such as calcium, iron, and salt that we need for such basic functions as muscles and nerves firing.

Dehydration is a lack of adequate body fluids for the body to carry on normal body functions. Fluid loss of 5% are considered mild, 10% moderate and up to 15% severe. Severe dehydration can result in cardiovascular collapse and death if not treated quickly.

Symptoms: sunken eyes, dry or sticky mucus membranes in the mouth, skin lacks normal elasticity, decreased urination, decreased tears.

WATER makes up more than half the weight of the human body. Without water, humans would die in a few days. All the cell and organ functions depend on water for functioning. It serves as a lubricant and forms the base for saliva and the fluids that surround the joints. It regulates the body temperature, as the cooling & heating are distributed through perspiration. Water helps to alleviate constipation by moving food through in the intestinal tract & thereby eliminate waste.

WHAT HAPPENS WHEN YOU DON’T GET THE

NUTRIENTS YOU NEED?

Kwashiorkor

Meeting energy requirements is basic to survival A diet with excessive nonprotein calories from starch or sugar, but deficient in total protein and essential amino acids, results eventually in kwashiorkor.

Kwashiorkor is characterized by generalized edema, "flaky paint' dermatosis, thinning and discolouration of the hair, enlarged fatty liver, and apathy in addition to retarded growth.

Symptoms: Weight loss of 25% or more, cold intolerance, constipation menstruation absent, skeletal muscle atrophy, low blood pressure, dental cavities, increased susceptibility to infection, blotchy or yellow skin, dry hair, hair loss and sometimes death.

Anorexia nervosa is an eating disorder associated with a distorted body image. Inadequate calorie intake results in severe weight loss.

Cheese pizza diet causes scurvy in 5-year-old July 17, 2000

NEW YORK (Reuters Health) - When it was discovered that sailors away at sea could stop their gums from bleeding by sucking on a lime, one of the first links between disease--in this case, a vitamin C deficiency--and diet became apparent. But a recent report illustrates that even modern-day children anchored at home are vulnerable to scurvy--a vitamin C deficiency that causes bleeding gums, loose teeth, muscle degeneration and weakness.

In one case, a 5-year-old boy ate nothing but Pop-Tarts, cheese pizza, biscuits and water for 5 months, according to a report in the July issue of the Archives of Pediatrics and Adolescent Medicine. He refused fruits, vegetables, juices and vitamins. The result? A case of scurvy--a disease seldom seen in developed countries today.

While the boy was playful, alert and appeared to be growing normally, he developed a limp and was

diagnosed with anemia. His gums became swollen and he developed small, purple spots on his skin.

Eventually, the pain was so severe he was unable to get out of bed or walk without assistance.

After ruling out leukemia or other ailments, the doctors diagnosed the youngster with a severe vitamin C deficiency, most likely caused by his unusual diet.

The doctors gave the boy vitamin C, which improved his pain and symptoms within a week.