Some important concepts. 1. glucose requirement is < 130 g/d

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1 A Protein-rich rich Diet as a Cornerstone of a Healthy Lifestyle Donald K. Layman, Ph.D. Professor of Nutrition Dept. Food Science & Human Nutrition University of Illinois at Urbana-Champaign Outline: protein needs: RDAs vs DRIs roles of protein and amino acids protein and adult health protein and diet quality potential health risks how to use protein in your diet Some important concepts 1. glucose requirement is < 130 g/d 2. all adults are insulin resistant 3. saturated fatty acids are bad only if you re overeating 4. adults need more protein than children 1

2 RDAs vs. DRIs Recommended Dietary Allowance (RDA) for protein = 0.8 gram/kg body weight Protein needs relate to BODY WEIGHT The lowest level of dietary protein intake that will balance the losses of nitrogen from the body, in persons at energy balance with modest levels of physical activity and in good health. The Protein Myth Adults eat more protein than they need! Protein Turnover and Aging Growth = synthesis > breakdown 16 y.o. = 260 g/d g/d [net: + 5 g/d] 60 y.o. = 250 g/d g/d [net: g/d] 2

3 How should we define macronutrient targets? MyPyramid Percentages: CHO = 55% Fat = 30% Prot = 15% Problems with Percentages USDA Food Guide Pyramid: (55% : 15% : 30%) kcal/day Carbs (g/d) protein (g/d) lipids (g/d) protein needs: 81 kg x 0.8 g/kg = 65 g/d Dietary Reference Intakes (DRI) Risk of Inadequacy RDA acceptable intake UL Risk of Adverse Affects 3

4 DRI: Acceptable Macronutrient Ranges* carbohydrates = 25 # to 65% protein = 10 to 35% fat = 20 to 35% * expressed as percentage of calories # RDA for carbohydrates = 130 g/d DRIs where do diets fit? RDA UL Atkins C P F PRO diet C F P MyPyramid P F C Ornish F P C Amino acid roles in the body - build new proteins (20 amino acids) - energy (15% to 20%) - other things i.e. neurotransmittors, creatine, etc -regulators and signals leucine, arginine, methionine 4

5 Outline: protein needs: RDAs vs DRIs roles of protein and amino acids protein and adult health protein and diet quality potential health risks how to use protein in your diet Branched-chain chain Amino Acids Leucine Valine Isoleucine CH 3 CH CH 2 CH 3 CH NH 2 COOH Metabolism of Branched-Chain Amino Acids Liver BCAA BCAA BCAA protein synthesis BCAA energy Intestine BCAA Muscle 5

6 The metabolic balance of leucine and insulin Insulin GLUT4 IRS-1 PI3-K Akt/ PKC glycogen synthesis Cell Membrane J. Nutr. 134: 968S, 2004 J. Nutr. 136: 533S, 2006 [leucine] mtor p70 S6 K eif4 protein synthesis Outline: protein needs: RDAs vs DRIs roles of protein and amino acids protein and adult health protein and diet quality potential health risks how to use protein in your diet U.S. Health Concerns obesity type 2 diabetes (and Metabolic Syndrome) sarcopenia osteoporosis heart disease cancer 6

7 Obesity Trends in U.S. Obesity is #1 public health problem in U.S. Incidence: > 60% of adults in U.S. overweight > 25% of adult are obese > 25% of children are overweight Outcomes with high protein, low Carb diets weight loss loss of body fat protein sparing TG (VLDL) HDL glycemic control Studies with high protein, low Carb diets Skov et al. Int J Obesity 23: 528, 1999 Parker et al. Diabetes Care 25: 425, 2002 Westman et al. Am J Med 113: 30, 2002 Layman et al. J Nutr 133: 405, 2003 Layman et al. J Nutr 133: 411, 2003 Foster et al. N Engl J Med 348: 2082, 2003 Farnsworth et al. Am J Clin Nutr 78: 31, 2003 Volek et al. Obes Res 12: 115S, 2004 Noakes et al. Am J Clin Nutr 81: 1298, 2005 Layman et al. J. Nutr. 135: 1903, 2005 Krieger et al. Am J Clin Nutr 83: 260,

8 Overview of diets diets with: 1700 kcal PRO diet: protein (> 1.5 g/kg.d) carbohydrates (< 170 g/day) fat ~ 30% of kcals Specific targets: Pro group: 40% carbohydrates, 30% protein, 30% fat CHO group: 55% carbohydrates, 15% protein, 30% fat Obesity studies using high protein diet Study wk diet study, prepared meals Study wk study, diet and diet + exercise restricted menus, highly supervised Study month diet study, free-living subjects weekly meeting with weigh-in in and 3-day weighed food records Experimental Design 16 wk weight loss study with 48 adult women Diets: CHO group: 55% carbs, 15% protein, 30% fat PRO group: 40% carbs, 30% protein, 30% fat Exercise: no EX: EX: < 100 min./wk of walking > 210 min. 5 d/wk walking + 2 d resistance training 8

9 Changes in Body Weight and Composition Diet effects CHO Groups Protein Groups Body weight (kg) * Fat mass (kg) * Lean mass (kg) Exercise effects EX no EX Body weight (kg) Fat mass (kg) -7.2* -5.5 Lean mass (kg) * Layman et al. J. Nutr. 135: 1903, 2005 * P < 0.05 Changes in Percent Body Fat % -3 * -4 # -5-6 * # -7 PRO PRO + EX CHO CHO + EX * Diet effect Treatment Groups # Exercise effect Changes in Blood Lipids (mg/dl) Diet effects CHO Groups Protein Groups total cholesterol LDL-C * HDL-C * TAG * Exercise effects EX no EX Total cholesterol LDL-C HDL-C TAG * P <

10 Obesity studies using high protein diet Study wk diet study, prepared meals Study wk study, diet and diet + exercise restricted menus, highly supervised Study month diet study, free-living subjects weekly meeting with weigh-in in and 3-day weighed food records. Changes in Body Weight and Subject Compliance PRO group CHO group Δ wt. N Δ wt. N 4 mo kg 82% kg 77% 12 mo all subjects kg 64%* kg 45% >10% loss kg* 31% kg 21% Changes in percent (%) body fat from 0 to 12 months 40 A P = **************************** 36 Baseline 12 m %Fat all subjects B P = **************************** %Fat >10% loss CHO PRO 10

11 Changes in blood lipids from 0 to 12 months LDL Cholesterol (mmol/l) 4.0 A 3.8 * HDL Cho lesterol (mmo ol/l) B * * PRO group CHO group C Triacylglycerol (log mmol/l) * * months Obesity and Risk for T2DM 70% of risk for T2DM attributed to excess weight (NIH, 2006) 67% of T2DM have BMI 27 46% of T2DM have BMI 30 If obesity causes T2DM how can 54% of cases not be obese? Glycemic Regulations liver glycogen diet gluconeogenesis [blood glucose] peripheral Non-insulin mediated ~ 4 g/hr Insulin mediated 11

12 Reduced Carbs & increased protein for management of type 2 diabetes Improves glycemic regulations in T2DM Parker et al. Diab. Care. 25: 425, 2002 Gannon et al. AJCN 78: 734, 2003 reduces FBG reduces meal AUC for glucose reduces meal AUC for insulin compensatory hyperinsulinemia reduces glycated hemoglobin percentage (HbA1c) Oral Glucose Tolerance in Insulin-Sensitive and Insulin-Resistant Obese Subjects Insulin Sensitive (n = 17) Insulin Resistant (n = 26) Fasting glucose (mmol/l) * Fasting insulin (pmol/l) * 2 hr glucose (mmol/l) hr insulin (pmol/l) * Glucose area (mmol/lx10-3 ) Insulin area (pmol/l x 10-3 ) * Postmenopausal women. Data are mean ± SD. *P = 0.01 Brochu M et al. J Clin Endocrinol Metab. 2001;86: Copyright 2001 The Endocrine Society Insulin and glucose meal response curves at 0, 4 and 10 wks for T2DM using PRO diet n = 9 12

13 Clinical Identification of the Metabolic Syndrome*: NCEP-ATP III *Diagnosis is established when >3 of these risk factors are present Risk Factor Abdominal obesity (Waist circumference) Men Women Triglycerides HDL-C Men Women Blood pressure Fasting glucose Defining Level >102 cm (>40 in) >88 cm (>35 in) >150 mg/dl <40 mg/dl <50 mg/dl >130 / >85 mm Hg >110 (>100**) mg/dl ** 2003 New ADA IFG criteria (Diabetes Care) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults. JAMA. 2001;285: ty Rate (%) Mortalit Metabolic Syndrome: Impact on Mortality * Without metabolic syndrome With metabolic syndrome * 0 All-cause Mortality *P < Cardiovascular Mortality Isomaa B et al. Diabetes Care. 2001;24: Impact of Moderate Protein Diet on Blood Lipids Krauss et al. AJCN 83: 1025, 2006 triglycerides (TAG) triglycerides (TAG) HDL LDL particle size total cholesterol/hdl 13

14 U.S. Health Concerns obesity type 2 diabetes sarcopenia = muscle wasting osteoporosis heart disease Dietary protein needs for adults Increased essential amino acids: Volpi et al. Am. J. Physiol. 277:E512, 1999 Volpi et al. J. Clin. Endocrinol. Metab. 85:4481, 2000 Aging reduces amino acid efficiency Aging reduces anabolic effects of insulin Dietary protein needs for adults Sedentary lifestyle: Campbell et al. J. Physiol. 542: 631, 2002 Millward J. Nutr. 1588S, 2004 protein needs physical activity 14

15 Outline: protein needs: RDAs vs DRIs roles of protein and amino acids protein and adult health protein and diet quality potential health risks how to use protein in your diet Protein intake and lifestyle quality Hu et al. AJCN 70: 221, 1999 Nurses Study Higher protein intake related to increased intake of: saturated fat and cholesterol whole wheat bread, fruits & vegetables Lower intake of sweets, desserts and white bread Increased exercise and lower smoking lower risk of heart disease Diet quality During calorie restriction (Layman et al ) - protein rich diet increased diet quality - high Carb diet decreased diet quality Significant differences: zinc and copper calcium and phosphorus vitamins A, C and E B 2, B 12 15

16 Outline: protein needs: RDAs vs DRIs roles of protein and amino acids protein and adult health protein and diet quality potential health risks - (kidney & bone) how to use protein in your diet Protein and Renal Function High protein intakes by patients with advanced renal disease contributes to deterioration of renal function. (Nephron 46: 37, 1987) with healthy subjects, protein intake has positive effects on kidney function and efficiency Eur. J. Clin. Nutr. 50: 734, 1996 J. Am. Soc. Nephrol. 2: 856, 1991 DRI protein intake protects renal function in aging Protein and Bone Health high protein diets increase urinary calcium J. Nutr. 128: 1051, 1998 but higher protein results in greater Ca absorption and greater bone mineral density J Clin Endocrinol Metab. 90: 26, 2005 Calcif Tissue Int. 58: 320, 1996 bone health = calcium + protein + exercise 16

17 Outline: protein needs: RDAs vs DRIs roles of protein and amino acids protein and adult health protein and diet quality potential health risks how to use protein in your diet Protein goals for adults Concepts: 1. 65% of protein consumed after 6:30 pm de Castro. Physiol Behav 40: 437, daily protein distribution Arnal et al. J. Nutr. 132: 1002, leucine threshold at each meal Layman J. Nutr. 133: 2615, 2003 Protein goals for adults 1. total daily protein goal 1.5 g/kg body weight or RDA = 0.8 g/kg plus metabolic = 60 g/day 2. daily protein distribution > 25 g of protein at breakfast and lunch 17

18 Protein goals for adults 2.5 g of 3 meals/day 30 g of 3 meals/d ~ 100 to 130 g protein/day A key for adults is correcting BREAKFAST Leucine Content of Foods leucine BCAA whey protein isolate 13% 26% milk protein 10% 21% egg protein 8.5% 20% muscle proteins 8% 18% soy protein isolate 8% 18% oat protein 8% 17% wheat protein 7% 15% Dairy breakfast Prot Carb Fat kcal blueberries (½ cup) cottage cheese (½ cup) plain li yogurt (½ cup) Equal Bran Buds (3 Tbs) turkey sausage (3 oz)

19 Egg breakfast Prot Carb Fat kcal egg Canadian bacon (2 oz) cheese slice English muffin (½) milk (1%) (1 cup) DKL breakfast Prot Carb Fat kcal Kefir ½ cup greek yogurt whey ypowder strawberries (3) Equal Wheaties (1 cup) milk (1%) Questions? 19