chapter 2 nutrition. 6 groups of nutrients: carbohydrates fats proteins vitamins minerals water

Chapter 2 Nutrition

6 groups of nutrients:Carbohydrates

FatsProteinsVitaminsMinerals

Water

Nutrient – a chemical substance in food that

helps maintain the body.

Nutrition – the study of how your body uses nutrients in the foods

you eat.

Malnutrition – a lack of the right proportions

of nutrients over an extended period.

Dietary Supplements are purified nutrients

that are manufactured or extracted from natural sources.

Diet ?

Diet =

the foods we eat

Fortified Foods are foods to which

nutrients are added in amounts greater than would naturally occur

in the food.

Enriched Foods are foods to which

nutrients have been added back that were

lost during processing.

Calorie – the unit used to measure the energy value of foods

Carbohydrates – one of the six basic types of nutrients that is the body’s chief source of energy.

Fats – one of the six basic types of nutrients that are important energy sources.

Proteins – one of the six basic types of nutrients that is required for growth, repair, & maintenance of every body cell.

Vitamins – one of the six basic types of nutrients that is a complex organic substance needed by the body in small amounts for normal growth, maintenance, & reproduction.

Minerals – one of the six basic types of nutrients that is an inorganic substance & becomes a part of the bones, tissues, & body fluids.

Digestion – the bodily process of breaking food down into simpler compounds the body can use.

Absorption – the process of taking in nutrients and making them part of the body.

Metabolism – the chemical processes that take place in the cells after the body absorbs nutrients.

Carbohydrates

Main Function:1.Supply energy to the

body Carbs should be our body’s

chief source of energy.

Types of Carbs

1.Simple Carbs – • sugars• broken down quickly by

the body to be used as energy

Food Sources: sugar, foods made with sugar, honey, jam, jelly, fruit, soda, sports drinks, candy, etc

2. Complex Carbs:Starches – • Body must break starch down

into glucose (blood sugar) in order for it to provide energy.

• Therefore, starch provides our body with a long, sustained energy that is not used up quickly.

Food Sources: Grains, beans, breads, cereals, corn, pasta, rice, potatoes

Fiber – • Main function – clean & keep

digestive tract healthy• fiber is not fully broken down in

our digestive tract

* 2 kinds of fiber –

soluble & insoluble

Soluble fiber –

Turns into a gel-like substance in the intestines and slows down digestion. During this process, the cholesterol level is lowered in the blood stream.

Insoluble fiber -

Speeds up the movement of food through the intestines & promotes regularity.

Food Sources: Whole grain breads & cereals, fresh fruits & vegetables, dry beans, nuts, seeds, popcorn

Men - 38 grams of fiber daily

Women - 25 grams of fiber daily

Carbohydrate Deficiencies:

Not common

Carbohydrate Excesses:

Calorie – the unit used to measure the energy value of foods

The calories you eat are either converted to physical energy or stored as body fat.

It takes about 3500 calories to gain/lose one pound of body weight.

Simple carbohydrate food sources

are high in calories (energy), but low in other nutrients. Complex carbohydrate foods are high in calories (energy), but supply energy for a longer period of time & usually contain some other vital nutrients.

Fats

Functions of Fats:• Energy• Carry fat-soluble vitamins throughout body (Vitamins A, D, E, & K)

• Make food taste good

• Make foods tender (meats & baked goods)

• Satiety – full feeling after eating

• Fatty tissue in body provides organ protection & body insulation

3 major types of fats:1. Unsaturated Fats – • Found in plant foods and fish. • Usually liquid at room temperature. • May be good for heart health because

they do not raise blood cholesterol levels.

Sources of Unsaturated Fats: olive oil, peanut oil, canola oil, tuna, salmon, olives, avocados

2. Saturated Fats – • Found in meat and other animal food

products. • Eating too much saturated fat can raise

blood cholesterol levels and increase heart disease.

• Usually solid at room temperature. Sources of Saturated Fats: Meat, dairy

foods (except skim milk), butter, cheese. Palm & coconut oils which are used in commercially baked foods. (The baked foods you buy at the store.)

3. Trans Fats – • Hydrogenation creates trans fats. • Hydrogenation is the process of turning

an oil into a solid by adding hydrogen atoms to the oil.

• Trans fats raise cholesterol levels and increase the risk of heart disease.

Sources of Trans Fats: margarine (especially the sticks), shortening, snack foods, baked foods, and fried foods. When you see “hydrogenated” or “partially hydrogenated” oils on the food label, the food contains trans fats.

Cholesterol: a fat-like substance found in every cell in the body.

• Our body produces the cholesterol it needs, but eating foods high in dietary cholesterol is thought to increase our risk for heart disease.

Sources of dietary cholesterol: high fat

meats, saturated fats, trans fats, liver, egg yolks

Fat Deficiencies:

Rare in the United States.

Excess Fats:

A diet high in fat is usually high in calories and can contribute to weight problems.

Experts recommend no more than 35 percent of the calories in your daily diet should come from fat.

Choose a diet moderate in fat by:

eating a variety of fruits, veggies, legumes, and whole-grain products

opt for lean meats, skinless poultry, and fish

choose low-fat and fat free dairy products

choose fats and oils that have less than 2 grams of saturated fat per serving

limit foods that list hydrogenated oils on their ingredient list

cook with vegetable oil instead of animal fat

Protein

Proteins: Chemical compounds found in every body cell

Functions of Protein:• growth, maintenance, &

repair of body tissues• formation of enzymes, some

hormones, & antibodies• regulate fluid balance in the

cells & other body processes

Amino Acids: Proteins are made up of small units called amino acids.

There are about 20 amino acids that are important to the human body.

9 amino acids must be consumed from food because they are not made by the body = essential amino acids

Essential Amino Acids: Histidine, Isoleucine, Leucine, Lysine, Methionine, Phenylalanine, Threonine, Tryptophan, and Valine.

Nonessential Amino Acids: Alanine, Asparagine, Aspartic Acid, Glutamic Acid.

Conditional Amino Acids: Arginine (essential in children, not in adults), Cysteine, Glutamine, Glycine, Proline, Serine, and Tyrosine.

Complete protein: Proteins that contain all 9 essential amino acids.

Animal foods, soybeans, and quinoa have complete protein and support growth & normal maintenance of body tissues.

Incomplete protein:

Proteins that are missing one or more of the essential amino acids.

Most plant foods have incomplete proteins.

By combining different plant sources of protein such as, rice & beans, you obtain all of the essential amino acids if they are consumed in the same day.

Sources of protein:

Complete protein - lean meats, poultry, fish, milk, cheese, eggs, soy beans & products, quinoa

Incomplete protein – dried beans, dried peas, nuts

How much do we need daily?

• Women ages 14 – 70+ need 46 grams

• Young men ages 14 – 18 need 52 grams

• Men ages 19 – 70+ need 56 grams

Protein Deficiencies – A diet low in calories and

protein may result in protein-energy malnutrition (PEM).

Symptoms include fatigue, weight loss, diarrhea, infections, & stunted growth.

Protein Excesses –

If a diet contains too much protein, the body converts the extra protein to fat & stores it in the fat tissue.

Vitamins

Vitamins are complex organic substances

needed in small amounts for normal

growth, maintenance, and reproduction.

Fat-soluble vitamins:•A,D,E, & K•dissolve in fats•are carried by fats to body tissues for use•stored in the body

Water-soluble vitamins:

•C & B •dissolve in water•not stored in the body

Vitamin AMain function:makes chemical compound the eyes need to adapt to darkness

Sources: liver, egg yolk, whole milk, *deep yellow & dark green fruits and vegetables

Vitamin A Deficiencies:

Night blindness, rough skin, stunted growth

Vitamin DMain function:•helps body use calcium & phosphorus

Sources: eggs, liver, fatty

fish, *vitamin D is added to most milk, *sunlight

Deficiencies: Children who do not receive enough vitamin D can develop rickets.

Vitamin EMain function:•Dietary Antioxidant – a substance in foods that reduces the harmful effects of oxygen on normal body functions

Forms of Vitamin EVitamin E exists in eight different forms: alpha-, beta-, gamma-, and delta-tocopherol; and alpha-, beta-, gamma-, and delta-tocotrienol. Alpha-tocopherol is the most active form in humans.

Sources: •*fats & oils, whole grain breads & cereals, liver, eggs, whole milk dairy foods, & leafy green vegetables

Deficiencies & Excesses:

Very rare in US.

Vitamin KKnow as the

blood-clotting vitamin.

Main function:

•Aids in blood-clotting by helping the liver make prothrombin.

Sources: *Leafy green vegetables, cauliflower, other vegetables, organ meats, egg yolk

Deficiencies & Excesses:

uncommon

Vitamin C

Also know as ascorbic acid.

Main functions:•helps in the formation & maintenance of collagen, a protein that is part of connective tissue

•helps the body fight infection

Sources: *citrus fruits, strawberries, cantaloupe, leafy green vegetables, green peppers, broccoli, cabbage, most fresh fruits & vegetables

Deficiencies: •Vitamin C is a water-soluble vitamin and cannot be stored in the body. •Need a daily supply.

•Scurvy – a disease with symptoms of weakness, bleeding gums, sore joints, poor appetite caused by too little Vitamin C

B-complex vitamins

Each B vitamin has distinct properties, however they work

together in the body.

B-Complex Vitamins

All B vitamins work to convert food into fuel. They do this by helping in the process to turn carbohydrates into glucose, fat into energy, and metabolize amino acids (protein) for growth & maintenance of body tissue.

Thiamin (B₁)Main function:Helps promote normal appetite & digestion

Sources:

Rich sources – wheat germ, pork, legumes, & whole grain and enriched cereals

Deficiencies:Beriberi – disease of the nervous system.

Severe cases lead to paralysis & fatal heart disturbances.

Riboflavin (B₂)Main functions:

•Helps cells use oxygen

•Helps keep skin, tongue, & lips normal

Glossitis (white splotches on tongue) Cheilosis (fissures on sides of mouth)

Sources: Organ meats, milk & milk products, eggs, oysters, leafy green vegetables, whole grain & enriched cereal products

NiacinMain function:

Helps keep the nervous system, mouth, skin, tongue, & digestive tract healthy

Sources: Muscle meats, poultry, milk, peanuts, & peanut butter

Deficiencies: Pellagra – skin lesions & digestive problems are initial symptoms. Mental disorders & death may follow if untreated.

Vitamin (B₆)Main function:Helps nerve tissue function normally

Sources: Muscle meats, liver, vegetables, & whole grain cereals

Folate

Main Function:Important in the diets of pregnant women since it has been shown to help prevent damage to the brain & spinal cord of unborn babies.

Folate prevents damage to brain & spinal cord of unborn babies.

Vitamin (B₁₂)Main function:

Plays a role in the normal functioning of cells in the bone marrow, nervous system, & intestines.

Sources: Animal protein foods, fortified cereals

Pantothenic Acid

Main function:Helps the body make cholesterol

Sources: Organ meats, yeast, egg yolk, bran, wheat germ, milk, dry beans

Pantothenic Acid (B5) is found in all plant & animal tissues.

BiotinFunctions:

Essential part of several enzymes

Helps with breakdown of fats, carbs, & proteins

Sources: chicken, eggs, milk, fresh veggies, fruit, wheat germ, whole grain breads & cereals

MineralsBecome a part of the bones, soft tissues, & bodily fluids.Help regulate body processes.

Calcium is the most abundant mineral in the body.

CalciumMain Function:Combines with phosphorus to build & strengthen bones & teeth.Almost all calcium is stored in bones and teeth, where it supports their structure and hardness.The body also needs calcium for muscles to move and for nerves to carry messages between the brain and every body part. In addition, calcium is used to help blood vessels move blood throughout the body and to help release hormones and enzymes that affect almost every function in the human body.

Other Functions:Helps blood clot & keeps heart & nerves working properly.Helps regulate the use of other minerals in the body.

Calcium is required for vascular contraction and vasodilatation, muscle function, nerve transmission, intracellular signaling and hormonal secretion….

Sources: Milk, yogurt, cheese, cottage cheese,Whole fish, green vegetables, broccoli(Remember, Cream cheese, sour cream, butter, etc are not a good source of calcium because the are made primarily with milk fat.)

Calcium Deficiencies:

Children – malformed bonesOsteoporosis – a condition in which bones become weak, porous, & brittle.

Children with severe calcium deficiencies may develop malformed bones.

Many teens & adults in the U.S. do not get the recommended daily intake of calcium. If the diet does not supply enough calcium, the body will take the calcium it needs from the bones. This becomes an increasing problem in old age, when bone mass naturally decreases. Osteoporosis can develop. It causes many hip & bone fractures, especially among older women. Complications from falls make osteoporosis a leading cause of crippling & death. Women are most afflicted because they have less bone mass than men. Osteoporosis is also related to hormone changes that take place in older women therefore, women who have gone through menopause are at the greatest risk of developing this disease.

“Osteoporosis” means porous bone. Our bones should be dense. Osteoporosis causes bones to be porous, they look more like a honeycomb than strong hard bone. (see next slide)

Porous bones break easily. Studies suggest that approximately one in two women and up to one in four men age 50 and older will break a bone due to osteoporosis. Doctors can correct osteoporosis. However, obtaining enough calcium can prevent it. This is especially important during the growth years when bones are developing, birth through teen years. Bone density reaches its peak from 30-35 years of age. That means our bones absorb calcium until we are about 35 years old. After about 35 years of age, mineral losses begin in both men and women. It is very important that you are getting enough calcium now in your teens to make sure your bones are dense.

Research has shown that being physically active throughout life can also help reduce the risk of osteoporosis. This is because weight-bearing activities, such as walking, help increase bone mass.

Getting too much calcium (from supplements) can cause constipation and possibly kidney stones. Other excess problems are just theories and have not been researched fully.

PhosphorusFunctions:Works with calcium to give strength to bones & teeth

Sources: meat, fish, poultry, eggs, milk & milk products

Some soft drinks also supply a fair amount of phosphorus in the form of phosphoric acid. It adds tartness to the soft drink.

There are no symptoms for phosphorus deficiencies, most people don’t have trouble getting the phosphorus needed in their diets.

Having too much phosphorus in the body is actually more common and more worrisome than having too little. The calcium to phosphorus ratio in the diet should be now lower that 1:2. It has been said that people who drink a lot of soft drinks and not much milk may have a lower calcium to phosphorus ratio. This can cause calcium to be pulled from the bones to correct the ratio. This is a cause of depleting the bones’ calcium supply which can lead to osteoporosis. That said, new research is noticing that it may not be the phosphorus that depletes the calcium in bones, but those who drink large quantities of soda tend to drink low amounts of calcium rich milk or consume less calcium rich foods.

Foods high in phosphorus: dairy foods, meats, fish, whole grains

MagnesiumFunctions:

•Regulates body temperature

•Helps muscles contract

•Helps cells use proteins, fats, & carbs

Sources: whole grains, nuts, beans, meat, dark

green leafy vegetables

Sodium, Chloride, & Potassium

Functions together:•Work together as a nutrient team to control osmosis.

•Known as ‘electrolytes.’

Sodium, chloride and potassium function in your body as electrolytes, small particles that carry an electrical charge.

These three minerals work to maintain the correct balance of water in your blood and cells, to control the passage of molecules into and out of your cells and to transmit the electricity that powers muscle contraction and nerve transmission.

Too much in your body, however, can lead to toxicity and unpleasant or even dangerous side effects.

Other functions:

• maintain the acid-alkali in the body

• help nervous system & muscles function properly

Sources:

•Sodium & Chloride: table salt, found naturally in many foods, but processed foods are by far the largest source in the U.S.

Processed foods???What are processed foods?

•Any food that has anything done to it to prepare for eating. So what foods are we talking about that are too high in sodium chloride?packaged foods (most), foods that are prepared & ready to eat (including restaurant & fast foods)

•Some processed foods make it easier for us to eat healthy, such as bagged greens, sliced fruit, canned vegetables & fruit (make sure they are low sodium & pack in water or their own juice) The process of canning, killing any bacteria at high heat then vacuum packing, should preserve the food, sodium & sugar do not need to be added as a preservative.

Sources:

Potassium: potatoes, sweet potatoes, tomato products, seafood, bananas, peaches, apricots

Deficiencies:Potassium intake is low in the diets of many people, but important because potassium helps people have a healthy blood pressure.

Excesses:Edema – swelling resulting from too much sodium intake and the body cannot get rid of the excess sodium and fluids build up.

Excesses:

Hypertension, or high blood pressure, is caused from consuming too much sodium

The best way to reduce sodium in the diet is to

limit your use of processed foods & limit

your use of salt in cooking & at the table.

Trace Elements – minerals our bodies need in very small

amounts

IronFunctions:

•Iron is a part of the protein hemoglobin which carries oxygen throughout our bodies. Hemoglobin is a protein pigment found in red blood cells. It takes oxygen from the lungs & carries it to cells throughout the body.

Sources:

meat, egg yolks, liver, leafy green vegetables, enriched grains

Deficiencies: Anemia – illness caused by low iron reservesSymptoms include fatigue & decreased mental function. Women & infants suffer from anemia more often than other groups of people.

Zinc

Functions:•Helps enzymes perform their functions

It is required for the catalytic activity of approximately 100 enzymes and it plays a role in

•Helps wounds heal & aids in functioning of immune system

•Promotes normal growth & development in children

Sources:

meat, poultry, seafood, legumes, & whole grains

Deficiencies:

poor wound healing, impaired taste, stunted growth & sexual development in children

Excesses:

fever, nausea, vomiting

Large doses of zinc supplements over time can develop heart failure & kidney failure.

Iodine

Functions:•Essential part of thyroxine.

Thyroxine is a hormone produced in the thyroid gland

that regulates the rate at which the body uses energy.

Large doses of zinc supplements over time can develop heart failure & kidney failure.

Sources: cheese, milk, salt water seafood, seaweed, iodized salt

Deficiencies: Goiter – a visible enlargement of the thyroid gland due to a diet lacking in Iodine.

Examples of Goiter

FluorineFunctions:•Resistance of tooth decayFluorine also help maintain bone structure. Low doses of fluoride salts may be used to treat conditions that cause faster-than-normal bone loss, such as menopause.

Sources: drinking water, may be added to water where natural fluorine level is low

Fluorine also help maintain bone structure. Low doses of fluoride salts may be used to treat conditions that cause faster-than-normal bone loss, such as menopause.

WaterFunctions:•aids in proper digestion, cell growth, & maintenance

•a part of all chemical reactions in the body

•lubricates the joints & body cells

•regulates body temperature

Your body takes the water it needs from the liquids

you drink and the foods you eat.

Drink water when thirsty, at meals, when sweating

excessively, and when sick.

• Your body tells you when it NEEDS water, don’t ignore it!

• When you feel thirst, it is important to rehydrate.

• Hydrate before you need it. • When you are sick with diarrhea,

vomiting, &/or fever, it is extremely important to hydrate.

Benefits of drinking water