PROTEIN NUTR 2030 Principles of Human Nutrition Mrs. Deborah A. Hutcheon, MS, RD, LD Lesson Objectives At the end of the lesson, the student will be able to: 1. Identify the structure & functions of protein. 2. Calculate total kcals from protein and total grams of protein that should be consumed daily given an individual s age, physical activity level, and total daily kcal allowance. 3. Differentiate between complete and incomplete dietary sources of protein. 4. Explain protein complementation and suggest complementary protein foods. 5. Discuss the consequences of too little and too much protein in the diet. 6. Summarize dietary strategies for ensuring nutritional adequacy for individuals following a vegetarian lifestyle. Protein s Role in the Body = Building Building blocks of muscle, bones, skin, cartilage, blood all body cells (structure) Building blocks for enzymes & hormones Building blocks for immunity (antibodies) Help store & transport nutrients Regulates fluid & acid-base balance 1
Structure of Proteins Primary Structure = 20 AA Secondary Structure Structure of Proteins Tertiary Structure Quaternary Structure Effects of Too Little Protein Protein Energy Malnutrition (PEM) Marasmus = skin and bones Chronic PEM severe deprivation or impaired use Signs: severe somatic muscle & fat wasting; preservation of visceral protein (organs) Kwashiorkor = bloated Acute PEM inadequate intake Signs: edema, visible nutrient deficiencies; preservation of somatic protein but wasting of visceral protein Sarcopenia: muscle loss with aging Aging promotes LBM & in lipogenesis 2
Effects of Too Much Protein Increased risk of heart disease and cancer high protein foods are also high in kcals & bad fat Increased risk of increased body weight high protein foods are also high in kcals Increased risk of kidney disease puts more stress on the kidney Calories in Protein 1 gram of protein = 4 calories How many protein calories are in 1 cup of milk (8 grams protein) 3 oz chicken (21 grams protein) Protein Intake Recommendations Recommended Macronutrient Proportions by Age CHO PRO FAT Young children (1-3 years) 45-65% 5-20% 30-40% Older children and adolescents (4-18 years) 45-65% 10-30% 25-35% Adults (19 years and older 45-65% 10-35% 20-35% 3
Protein Intake Recommendations Classification Amount RDA Non-Athlete Recreational Athlete Endurance Athlete Power Athlete 0.8 g/kg 1.1 to 1.4 g/kg 1.2-1.4 g/kg 1.2-1.7 g/kg Male: 56 g Female: 46 g 82 kg (180#) Male:90-115 g 60 kg (132#) Female: 66-84 g 82 kg Male: 98-115 g 60 kg Female: 72-84 g 82 kg Male: 98-139 g 60 kg Female: 72-102 g Meat, Poultry, Fish Eggs Dairy Legumes Nuts & Seeds Foods High in Protein Webb D. Today s Dietitian. 2014;16(6):23. Foods Low in Protein Fruit Vegetables Grains 4
Is this food HIGH or LOW in Protein? Is this food HIGH or LOW in Protein? Classification of Amino Acids Conditionally Indispensable (Indispensable AAs) (Dispensable AAs) 5
Food Sources of Protein Complete Proteins: meat, poultry, fish, dairy, eggs, soybeans, quinoa (High Quality Proteins) vs. Incomplete Protein: grains, legumes, nuts, seeds, gelatin Mutual Supplementation (Protein Complementation) Grains, Nuts, Seeds = limited lysine (high in methionine) Legumes (Peanuts) = limited methionine (high in lysine) Activity Break Your pregnant patient Susie is a vegan. As her nurse, you are concerned about her getting enough complete protein in her diet to support the growth and development of her baby since she doesn t eat any animal products. What incomplete protein foods would you recommend for her to eat in combination (protein complementation) to get a good source of complete protein in her diet? What are some Grain + Legume food combinations? Protein Balance Occurs in the Liver To the Kidneys for Excretion Glucose or Fat Occurs in the Mitochondria (TCA Cycle) Negative Nitrogen Balance (catabolism) = intake < excretion Positive Nitrogen Balance (anabolism) = intake > excretion 6
Critical Thinking Break What type of patients are prone to be in negative nitrogen balance? How can this be corrected? What type of patients are prone to be in positive nitrogen balance? The Value of Dietary Protein Source: Hoffman JR, Falvo MJ. J Sports Sci Med. 2004;3(3):118-130. Phenylketonuria (PKU) Autosomal recessive disorder (genetic) Defect in phenylalanine hydroxylase: conversion of phenylalanine to tyrosine Phenylalanine-restricted diet Tyrosine supplementation Results in neurological defects & hyperactivity 7
Vegetarian Diets Meat & Poultry Foods Included Fish & Seafood Eggs Dairy Plant Foods Flexitarian? X X X X Lacto-Vegetarian X X Ovo-Vegetarian X X Lacto-Ovo-Vegetarian X X X Pescetarian X X Macrobiotic X Vegan X Raw Food X Fruitarian X No Grains Nutrients of Concerns (Deficiencies) Nutrient Rationale Solution Complete Protein Vitamin B12 Iron Calcium Vitamin D Clinical Application Ms. Abigail is a 75 yr old female hospitalized with a broken hip. She has some missing teeth, so it makes it difficult for her to chew certain foods. She is eating 25% of her meals including her entrees. She states milk constipates her, so she does not drink it except in her coffee. She is 5# underweight. Are there any nutritional concerns? What types of foods would you recommend for her to improve nutritional intake? 8