Chapter 5 - Nutrition Basics

What do your nutritional habits help determine?

The risk of major chronic illness, including heart disease, cancer, stroke and diabetes.

Define nutrition

The science of food and how the body uses it in health and disease.

What does caloric needs depend on?

• age

• body size

• sex

• activity level

• whether a person is breastfeeding or pregnant

Define vitamins

Organic (carbon-containing) micronutrients needed in small amounts for normal gowth, reproduction and maintenance of health.

How do vitamins act as coenzymes?

They facilitate action of enzymes to help initiate a variety of chemical body responses such as:

• energy production

• use of minerals

• growth of health tissue

What do antioxidants do and what vitamins are they?

They help preserve health cells in the body. Key vitamin antioxidants include:

• vitamin e

• vitamin c

• vitamin a precursor beta-carotene

How many vitamins do humans need?

13

• 4 fat soluable

• 9 water soluable

What are the fat soluable vitamins?

• Vitamin A

• Vitamin D

• Vitamin E

• Vitamin K

What are dietary sources of Vitamin A?

• liver

• milk

• butter

• cheese

• fortified margarine

• carrots

• spinach

• other orange and deep-green veggies and fruits

What are the major functions of Vitamin A?

• mainteneace of vision

• skin

• linings of the nose, mouth, digestive and urinary tracts

• immune function

What are dietary sources of Vitamin D?

• fortified milk and margarine

• fish oils

• butter

• egg yolks

• sunlight on skin*

What are the major functions of Vitamin D?

• development and maintenance of bones and teeth

• promotion of calcium absorption

What are dietary sources of Vitamin E?

• vegetable oils

• whole grains

• nuts and seeds

• leafy veggies

• asparagus

• peaches

What are the major functions of Vitamin E?

• protection and maintenenace of cellular membranes

What are dietary sources of Vitamin K?

• green leafy veggies

• smaller amounts widespread in other foods

What are the major functions of Vitamin K?

• production of factors essential for blood clotting and bone metabolism

What are the six classes of essential nutrients?

• protiens

• fats

• carbs

• vitamins

• minerals

• water

Define essential nutrients

Substances the body must get from foods because it cannot manufacture them at all or fast enough to meet its needs; include proteins, fats, carbohydrates, vitamins, minerals, and water.

How many essential nutrients are there?

50

Define digestion

A process by which the foods you eat are broken down into compounds your gastrointestinal tract can absorb and your body can use

Define macronutrients

Essential nutrients required by the body in relatively large amounts.

Define mirconutrients

Essential nutrients required by the body in smaller amounts.

What is the function of protien?

• forms important parts of muscles, bone blood, enzymes, some hormones and cell membranes

• repairs tissue

• regulates water and acid base balance

• helps in growth

• supplies energy

What are the major sources of protien?

• meat

• fish

• poultry

• eggs

• milk products

• legumes

• nuts

What is the function of carbs?

• main source of energy

• supplies energy to cells in brain, nervous system and blood

• supplies energy to muscles during exercise

What are the major sources of carbs?

• grains → breads and cereals

• fruits

• veggies

• milk

What is the function of fats?

• supplies energy

• isulates, supports and cushions organs

• helps absorption of fat soluable vitamins

What are the major sources of fats?

• animal foods

• grains

• nuts

• seeds

• fish

• veggies

What is the function of vitamins?

• promotes (initiats or speeds up) specific chemical reactions within cells

• help unleash the energy store in carbs, proteins and fats

• critical in the production of re blood cells and the maintenance of the nervous, skeletal and immune systems

• some act as antioxidants

What are the major sources of vitamins?

• fruits

• veggies

• grains

• meat

• milk

What is the function of minerals?

• helps regulate bofy functions

• aids in growth and maintenance of body tissues

• acts as catalysts for release of energy

What are the major sources of minerals?

• found in most food groups

What is the function of water?

• makes up ~ 60% of body weight

• provides medium for chemical reactios

• transports chemicals

• regulates temperature

• removes waste products

What are the major sources of water?

• fruits

• veggies

• liquids

Define kilocalories/calories

Measure of energy content in food; 1 kilocalorie represents the amount of heat needed to raise the temperature of 1 litre of water by 1 degree Celsius.

How many kilocalories does a person need a day to meet their energy needs?

2000

What three classes of essential nutrients supply energy?

• fat → 9 calories / gram

• protein → 4 calories / gram

• carbs → 4 calories / gram

note that these are also macronutrients

Define protein

Essential nutrient; a compound made of amino acids that contains carbon, hydrogen, oxygen, and nitrogen.

Define amino acids

The building blocks of proteins.

How many amino acids are essential?

9

How many amino acids can be produced by the body?

11

How many common amino acids are there?

20

What are complete proteins?

Proteins that supply all the essential amino acids in adequate amounts. Eg:

• meat

• fish

• poultry

• eggs

• milk

• cheese

• soy

What are incomplete proteins?

Proteins that do not supply all the essential amino acids and come from plant sources. Eg:

• legumes

  • beans

  • peas

  • lentils

• nuts

What are fats also known as?

Lipds

Define fats

The most concentrated source of usable energy @ 9 calories / gram

What two fats are essential compnents of the diet?

1. linoleic acid

2. alpha-linolenic acid

What type of fat are linoleic acid and alpha-linolenic acid? (saturated, polyunsaturated or monounsaturated)

polyunsaturated

Is linoleic acid an omega 3 fatty acid or omega 6 fatty acid?

omega 6

Is alpha-linoleic acid an omega 3 fatty acid or omega 6 fatty acid?

omega 3

What are the functions of lineoleic and alpha-linolenic acid?

they are used to make compounds that are key regulators of many body functions, such as the maintenance of blood pressue and the progess of a healthy pregnancy.

What is the biochemical compostition of most food fats?

A triglyceride → a molecule of glycerlol with three fatty acids

What are food fats usually composed of?

1. saturated fatty acids

2. unsaturated fatty acids

Food fats containing large amounts of saturated fatty acids are usually ______ at room temperature.

Solid

Food fats containing large amounts of monounsaturated and polyunsaturated fatty acids are usually ______ at room temperature.

Liquid

What are the sources of saturated fatty acids in food?

animal products:

• red meats

• homogenized milk

• cheese

• hot dogs

• lunchmeats

What are the sources of monounsaturated fatty acids in food?

plant products:

• olive oil

• canola oil

• peanut oil

• safflower oil

What are the sources of polyunsaturated fatty acids in food?

plant products:

• soybean oil

• corn oil

• cottonseed oil

Can trans fats be naturally occuring?

Yes, in small amounts.

Define hydrogenation

A process by which hydrogens are added to unsaturated fats, increasing the degree of saturation and turning liquid oils into solid fats. Hydrogenation produces a mixture of saturated fatty acids and standard and trans forms of unsaturated fatty acids.

Why is hydrogenation used?

• increases stability of oil so it can be reused for frying

• improve texture of foods

• increase shelf life

What are trans fats?

A type of unsaturated fatty acid produced during the process of hydrogenation; trans fats have an atypical shape that affects their chemical activity.

What are some dietary sources of trans fats?

• deeo fried foods

• baked and snack foods

• stick margarine

Why are health experts concerned about Canadian’s consumption of trans fats?

• they have triple negative effects on heart health

  • raises total cholesterol LDL (low-density lipoprotein)

  • lower HDL (high-density lipoprotein)

  • produce inflammation in blood vessels

Why are monosaturated fats better for you?

• raises HDL

• decreases risk of heart disease

Define omega 3 fatty acids

Polyunsaturated fatty acids commonly found in fish oils that are beneficial to cardiovascular health.

What is the function of omega 3s

• reduce the blood clot tendency

• inhibits inflammation and abnormal heart rythms

• reduces blood pressure and risk of heart attack and stroke in some people

What do dietitians reccomend in regards to omega-3?

Canadians should increase the porptions of omega 3 in their diet by eating fish twice a week.

What fats should you consume less?

• saturated

• trans

What fats should you consume moderately?

• monosaturated

• polyunsaturated

  • omega 3 fatty acids

  • omega 6 fatty acids

What is the biochemical compostition of carbohydrates?

Various combinaions of sugar units called saccarides.

What are the two classifications of carbs?

• simple

• complex

What is the function of simple carbs?

Provides natural sweetness to foods.

What do simple carbs include?

• sucrose

• fructose

• maltose

• lactose

What are some food sources of simple carbs?

• fruits

• milk

• honey

What do complex carbs include?

• starches

• fibre

• most imortant dietary carbs

What are some food sources of complex carbs?

• grains

• legumes

• tubers → potatoes and yams

What essential nutrients are unrefined complex carbs (whole grain) high in?

• fiber

• vitamins

• minerals

• other compounds

Why do complex carbs enter the bloodstream slowly?

They take longer to digest.

Define fibre

Non digestible carbs from plants.

What is the function of fibre?

It isn’t digested, but passes through the intesitnal tract and procided bulk for feces in the large intestine in facilitates waste elimination. In the large intestine some tyhpe of fibre are broken down by bacteria into acids and gases, which is why too much fibre leads to intestinal gas.

What are the benfits of fibre?

• decrease risk of type 2 diabetes and heart disease

• improve gastrointestinal health

What are the two types of fibre?

• dietary (normal)

• functional (isolated or synthesised in a lab)

Define minerals

Inorganic (non-carbon-containing) compounds needed in relatively small amounts for regulation, growth, and maintenance of body tissues and functions.

How many essential minerals are there?

17

Define major minerals (macrominerals)

Minerals that you need in larger amounts. >100mg per day

What are exampels of major minerals?

• calcium

• phosporus

• magnesium

• sulphur

• sodium

• potassium

• chloride

Define trace minerals

Minerals that you need in smaller amounts.

What are examples of trace minerals?

• zinc

• iron

• copper

• selenium

• iodine

• flouride

Define osteroporosis

A condition in which the bones become dangerously thin and fragile over time.

How many Canadians are living with osteoporosis?

Approximately 2 million.

How long can you live without food?

Up to 50 days

How long can you live without water?

A few days

When the body uses oxygen or breaks down certian fats or proteins as a normal part of metabolism, it gives rise to:

free radicals

What type of enviornmental factos can increase free radical production?

• excessive sunlight

• certain drugs

• stress

What does DRI stand for?

Dietary Reference Intakes

What does RNI stand for?

Recommended Nutrient Intakes

What are the Dietary Reference Intakes

• Standards for nutrient intake designed to prevent nutritional deficiencies and reduce the risk of chronic disease.

• Frequently reviewed as new nutrition related information becomes available

• broader focus

When was the first official food rules published?

1942 (WWII)

What was the purpose of the orginal food rules?

It was a wartime nutrition program to improve the health of Canadians in the context of rationing and poverty.