Nutrition

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• Trans fats are the most unhealthy and dangerous fats to consume.

• Recently there has been a trend to limit the consumption of trans fats.

• Trans fats are used to convert unsaturated fats to saturated fats in a process called hydrogenation.

• Hydrogenated fats have a higher melting point which is useful in cooking and it also extends the shelf life of products.

• Currently, the Canadian Minister of Health has made recommendations on limiting the trans fat contents of foods manufactured and sold in Canada.

And here is what Health Canada has to say about these trans fats…

• http://www.hc-sc.gc.ca/fn-an/nutrition/gras-trans-fats/index-eng.php

• Fats play an important role in the proper functioning of your cells.

• It is never wise to completely eliminate fats from a diet.

• Limiting the unhealthy saturated fats and avoiding trans fats is recommended.

• Consuming unsaturated fats and polyunsaturated fats is essential to having a healthy body.

Proteins• Proteins are the most important and most

abundant biochemical macromolecule in your body.

• They are a major structural component of human tissue including skin, muscles, and organs.

• In addition, they also serve as enzymes for the chemical reactions that take place within cells.

• All proteins are made up of amino acids.

• Amino acids consist of an amino group, a carboxyl group and a side chain (shown as R in the image on the right).

• There are 20 different amino acids.

• Of that 20, eight are considered to be essential and must come from the diet.

• Amino acids are linked together by peptide bonds to form a long chain.

• Interaction of the different R groups causes the chain to form kinks or bends.

• The final shape of a protein plays an important role in determining its functionality. Foods that have a high content of protein include meat, fish, beans, nuts and eggs.

• http://www.wisc-online.com/objects/index_tj.asp?objID=AP13304

Vitamins• Vitamins are essential components of a

healthy diet. Even though they lack nutritional value they have a role in cellular functions.

• You may take a vitamin supplement every day to help meet the needs of your body.

• Vitamins provide cells with organic compounds that are needed to carry out biochemical reactions in cells.

• Vitamins are not a source of energy and should only be taken in small amounts.

• Examples of some vitamins include: A, B, C, and K.

• Most vitamins can be found in fruits, vegetables, eggs and milk.

Minerals• Minerals, like vitamins, provide no nutritional value but are

extremely vital to cell functions. • Minerals are inorganic compounds that can be obtained from

the diet or as a supplement. • They include iron, magnesium, calcium, and sodium. Iron is a

component of hemoglobin that transports oxygen to the cells of the body.

• When people have low iron they will feel tired and lethargic because the hemoglobin molecule cannot function properly without iron.

• Calcium is essential for bone and teeth formation. • Natural sources of minerals include fruits, vegetables, meat

and whole grains.

Water• Water is the most abundant substance on Earth and also in your

body. • Water does not provide any nutritional value, but its presence

within the body and cells is critical for survival. • Water aids in the movement of materials with the body. It is

needed in most biochemical reactions and it lubricates organs, tissues, and cells.

• Water is also needed as a way to reduce body temperature. Sweat is produced when the body temperature increases e.g. you are exercising on a hot day. The water evaporating from your skin provides a cooling effect that attempts to lower body temperature.

• If there is an insufficient amount of water in the body, dehydration can occur and serious consequences may result.

Diet• Not sure of what you should eat or how many

servings? • You, as well as millions of people, struggle with all the

food choices that are available. • So many processed foods are readily available and

quick to prepare that they are often found on breakfast, lunch, and dinner menus.

• Health Canada has produced a document titled Eating Well with Canada's Food Guide.

• This guide can help you choose appropriate serving sizes and food types to meet your nutritional needs. You will revisit this guide again in a later activity.

Questions1. Create a table that compares carbohydrates, fats, and

proteins. Include the basic unit, function, and foods that contain the nutrients.

2. Many illnesses are caused by a lack of vitamins or minerals. Determine the cause of scurvy, rickets, anaemia, osteoporosis and goitre.

3. There are different types of fats. What is the difference between a saturated and unsaturated fat? What are trans fats?

4. According to Canada's Food Guide, list the four main food groups and indicate the number of servings males and females in their teens need from each group. Hypothesize why males have higher nutritional needs during this age.

AnswersNutrient Basic Unit Function Food Source

Carbohydrates Monosaccharide Energy source Whole grains, potatoes, rice

Fats Triglyceride Energy source, insulation, hormones

Milk, oils, meat, fish

Proteins Amino acid Structures, enzymes, antibodies.

Fish, eggs, meat, beans

AnswersIllness Deficiency

Scurvy Vitamin C

Rickets Vitamin D

Anemia Iron

Osteoporosis Calcium

Goitre Iodine

Answers• A saturated fat comes from animals and is solid at room

temperature. Saturated fats contain the most hydrogen atoms possible for each carbon atom. Saturated fats are saturated with hydrogen.

• Unsaturated fats contain carbon atoms that are double bonded. This reduces the number of hydrogen atoms in the fatty acid. Unsaturated fats are liquid at room temperature and come from plants.

• Trans fats are added to unsaturated fats in a process called hydrogenation. Hydrogen atoms are added to break apart the double bonded carbon atoms. This process converts an unsaturated fat to a saturated fat. Trans fats are dangerous to consume and are currently being restricted in manufactured foods.

Answers Females (14 - 18) Males (14 - 18)

Vegetables and Fruits 7 8

Grain Products 6 7

Milk and Alternatives 3-4 3-4

Meat and Alternatives 2 3

During this age, boys and girls start to mature and develop differently. Males are generally bigger and therefore require more food to meet the demands of growing bones, muscle, skin, and organs.