2. What Are Proteins?  The word “Protein” comes from the Greek word proteios, meaning primary.  Play arguably the most critical roles in the body  The make up of our cells and tissues  Found in our: Muscles Bones Hair Bone Nails Skin  20 Percent of our total body weight

3. Protein Functions  Antibodies specialized proteins involved in defending the body from antigens  Contractile Proteins responsible for movement  Enzymes proteins that facilitate biochemical reactions referred to as catalysts ex. Lactase and Pepsin

4. Protein Functions (cont.)  Hormonal Proteins proteins which help to coordinate certain bodily activities ex. Insulin  Structural Proteins provide support ex. keratin, collagen  Storage Proteins store amino acids  Transport Proteins carrier proteins which move molecules ex. hemoglobin

5. The Structure of Proteins  Proteins are polymers of amino acids covalently linked through peptide bonds into a chain.  20 different amino acids that make up all proteins  Amino Acids are composed of a central carbon atom bonded to: hydrogen carboxyl group amino group unique side chain or R-group  The unique side chains create different chemical properties on amino acids

6. The Structure of Proteins (Cont.)

7. Protein Digestion  Digested by enzymes called proteases  Protein digestion begins in stomach  Broken down by pepsin into polypeptides  Left over proteins digested by trypsin in small intestine  Polypeptides produced are further digested to amino acids by erepsin in intestinal juices  End product = Absorbable Amino Acids

8. Protein Digestion (cont.)  http://www.youtube.com/watch?v=AEsQ xzeAry8

9. Proteins in our Diet  Two types of Amino Acids:  Essential 8 – cannot be made in sufficient amounts in the body, must be supplied through food  Non-essential 12 – can be made from other amino acids in the diet  Foods with animal protein satisfy the essential amino acid needs Meat, Milk, Eggs, etc.  Vegetable protein sources have less than the necessary amounts

10. Proteins in our Diet (cont.)  10-15% of total caloric intake 0.75g of protein per kg of body weight per day  2-3 servings of animal protein foods will reach requirements  4-5 servings of vegetable protein sources will reach requirements Whole grain cereals, legumes, nuts, vegetables, etc.

11. Protein Related Health Concerns  High protein diets can lead to: Unpleasant body odour and bad breath Increased risk of high blood fat levels Loss of muscle tissue Risk of deficiency diseases  Excessive animal protein intake has been associated with: Mineral loss - leading to cancer Osteoporosis kidney stones Arthritis Diabetes Cataracts Arteriosclerosis  The average North American should reduce intake by 15% Less animal proteins more vegetable proteins

12. Protein Related Health Concerns (cont.)  Protein Deficiency: Your body cannot survive without adequate amounts of protein, a lack of this macronutrient will result in serious health problems  Symptoms: Weight loss, Thinning or brittle hair, hair loss, Skin rashes, dryness, flakiness, General weakness and lethargy, Muscle soreness and weakness, cramps, Slowness in healing, Bedsores and other skin ulcers, Difficulty sleeping, etc.  Risks: Gallstones, Arthritis, Heart problems, Muscle deterioration, Organ failure, Death

13. An Athlete’s Protein Needs  Athletes require protein to repair/rebuild muscle that is broken down during exercise  Should not be a substitute for carbohydrates  More effective to abide by the “less more often” rule  Average adult requires 0.8g per kg of body weight per day  Strength training athletes need 1.4 - 1.8  Endurance athletes need 1.2 – 1.4

14. Common Misconceptions:  You can not get enough protein on a vegetarian diet  You can only assimilate 30 grams of protein at one sitting. The body has the ability to digest and assimilate much more than 30 grams of protein from a single meal.  Protein must be rapidly digested to build muscle. Both rapidly and slowly digested proteins offer significant benefits to athletes

15. The End Thanks for your attention