Emerging Perspectives on Dietary Protein: Translating the Science into Practical Application

Transcription

1 Emerging Perspectives on Dietary Protein: Translating the Science into Practical Application Matthew Pikosky, PhD, RDN Vice President, Nutrition Science & Partnerships National Dairy 1

2 Key Points Maintaining muscle is important in support of overall health Routine exercise & balanced nutrition are critical for maintaining muscle Protein recommendations: meeting requirements vs. optimizing health outcomes Protein quality: significance to energy efficient and nutrient dense meal plans Dairy foods and ingredients provide a variety of convenient, nutrient rich and flavorful options to obtain high quality protein There is room for adults to increase their protein intake and/or shift their pattern of intake 2

3 Protein is an essential nutrient required by our body every day Amino acids: building blocks of protein; provides structural components needed for a number of critical body functions o Strong musculoskeletal system o Transporting oxygen to muscles o Metabolism of other nutrients o Healthy immune function 3

4 Changes in muscle size and strength with aging: Reduced muscle quality fat Muscle Quad muscle area Mid-thigh of a 25 year old versus a 75 year old Muscle torque Delmonico MJ et al., Am J Clin Nutr

5 Reduced muscle strength & function is associated with increased mortality men, leg strength & mortality Walking speed, BMI & mortality Newman AB et al., J Gerontol A Biol Sci Med Sci Cesari M et al., J Gerontol A Biol Sci Med Sci

6 Considerations for maintaining muscle mass & function Synthesis Balance Breakdown Muscle growth Malnutrition Inactivity Illness/Injury Hormones Exercise Protein Nutrition Muscle loss Figure adapted from Doug Paddon-Jones, PhD, UTMB Galveston 6

7 Protein Quantity 7

8 Protein recommendations: minimum requirements vs. optimizing health RDA: 0.8 g/kg BW/d for adults o estimate of the minimum daily average dietary intake level that meets the nutrient requirements of nearly all (97 to 98%) healthy individuals Acceptable Macronutrient Distribution Range (AMDR): 10-35% total calories o a range of intakes for a particular energy source that is associated with reduced risk of chronic diseases while providing adequate intakes of essential nutrients Research supports some may benefit from protein intakes greater than the RDA o Athletes / highly active adults o Older adults o Those interested in weight management Wolfe RR & Miller SL, JAMA 2008 Rodriguez NR & Miller SL, Am J Clin Nutr

9 Sports & Exercise: Protein is needed to support muscle recovery from routine, vigorous exercise Suggested Daily Intake: g protein/kg body weight/day o 150 lbs: ~82 136g protein / day Suggested Meal Intake: Aim for 20-30g of high quality protein (providing ~10g essential amino acids) after workouts and at main meals ( g/kg body weight) the performance of, and recovery from, sporting activities are enhanced by wellchosen nutrition strategies. Thomas DT et al., J Acad Nutr Diet,

10 Protein Levels Healthy Aging: New recommendations from international expert groups call for higher protein intakes in older adults 150%* Up to 2.0g/kg 0.8g/kg RDA (19-70+yrs) %* g/kg minimum protein intake for healthy people 2, %* g/kg acute or chronic disease 2,3 severe illness or injury, or marked malnutrition 2 Additional Recommendations g of protein per meal g of leucine per meal Current 1 New Recommendations >65 years 2,3 *increase above current Protein RDA 1 Older people with severe kidney disease who are not on dialysis may need to limit protein intake. 1. U.S. Department of Health and Human Services and U.S. Department of Agriculture. Dietary Guidelines for Americans, th Edition, Washington, DC: U.S Government Printing Office, January Bauer J et al., JAMDA Deutz NEP et al., Clinical Nutrition, 2014 Slide adapted from Stu Phillips, PhD, SCAN Annual Meeting

11 Anabolic resistance with aging: Higher essential amino acid / leucine threshold Clinical Trails of Note Volpi, J Clin Edocrinol Metab 2000 Paddon-Jones, Am J Physiol 2004 Cuthbertson, FASEB J 2005 Katsanos, Am J Clin Nutr 2005 Symons, JADA 2009 Breen L & Phillips SM, Nutr Metab

12 Per meal recommendations: ~20 g of high quality protein maximizes muscle protein synthesis in young adults ~ 8.6g EAA Age: 22 ± 2 years ~ 8.6g EAA Age: 22 ± 2 years ~ 10 g EAA Age: 22 ± 2 years Means with different letters are significantly different from each other (p<0.01) Moore DR et al., Am J Clin Nutr, 2009 *,# Means with different symbols are significantly different from each other (p<0.05) Witard OC, et al., AM J Clin Nutr,

13 Per meal recommendations: Up to 40g of high quality protein may be needed to maximize muscle protein synthesis in older adults Non-exercised leg Exercised leg Age: 70 ± 4 years Age: 73 ± 2 years Means with different symbols are significantly different from each other (p<0.05) within same condition (non-exercise, exercise) Yang Y et al., Br J Nutr, 2012 *Significantly different compared with 10g (p<0.05) significantly different compared with basal (p<0.05) Pennings B et al., Am J Physiol Endocrinol Metab,

14 Protein Quality 14

15 Essential Amino Acids 20 amino acids are needed for the body to make protein 9 essential amino acids are not made by the body and must be provided by the diet Essential amino acids, the branched chain amino acids, and leucine in particular stimulate and support muscle protein synthesis 15

16 Only essential amino acids are needed to support muscle protein synthesis MAA = 6g mixed amino acids EAA = 6g essential amino acids MAA + CHO = 6g mixed amino acids + 35g carbohydrate EAA + CHO = 6g essential amino acids + 35g carbohydrate Borsheim E et al., Am J Physiol Endocrinol Metab

17 Leucine is the key essential amino acid driving muscle protein synthesis Phillips SM, Nutrition & Metabolism

18 Whey protein promotes greater MPS compared to soy protein after resistance exercise *Significantly different from casein for same condition (P 0.01). # Significantly different from soy for same condition (P 0.05). All values are means SD; n 6 per group. Tang JE et al., J Appl Physiol,

19 Whey protein augments gains in lean body mass with resistance training greater than soy protein and carbohydrate 3.3 kg Whey Whey 2.3 kg 1.8 kg Soy Soy CHO CHO Volek JS et al., J Am Col Nutr,

20 Milk promotes greater MPS and improvements in body composition with resistance exercise training Protein and calorie matched milk and soy beverage (~175 kcal, 18g protein) or calorie matched carbohydrate provided immediately and Protein 1 hour and following calorie resistance matched milk training and soy (5d/week beverage for 12 weeks) (~180 kcal, 18g protein) provided following single bout of resistance exercise Wilkinson SB et al., Am J Clin Nutr 2007 Hartman JW et al., Am J Clin Nutr

21 Protein Timing 21

22 Consume moderate amounts of high quality protein at each meal to maximize muscle protein synthesis throughout the day Paddon-Jones D and Rasmussen BB, Curr Op in Clin Met Care,

23 Even distribution of protein intake promotes greater 24-h MPS vs. skewed intake 7-d crossover feeding design with 30-d washout Diets matched for total energy & protein intakes EVEN Protein Breakfast: ~30 g Lunch: ~30 g Dinner: ~30 g SKEW Protein Breakfast: ~11 g Lunch: ~16 g Dinner: ~63 g 24-hr muscle protein synthesis assessed days 1 & 7 Mamerow MM et al., J Nutr, 2014 *Significant difference from EVEN at that time point (p<0.05) # Main effect of group between EVEN and SKEW (p<0.05) 23

24 Putting the Science into Practice: Critical role of essential amino acids in context of protein requirements and recommendations has been Lost in Translation 24

25 Recommendations based on research investigating per meal protein amounts to maximize muscle protein synthesis ACSM, AND, DC Position Stand: Nutrition and Athletic Performance, 2016: Aim for 20-30g of high quality protein (providing ~10g essential amino acids) after workouts and at main meals PROT-AGE Study Group Position Paper: Evidence-Based Recommendations for Optimal Dietary Protein Intake in Older People, 2013: 25-30g of protein per meal g leucine per meal Dose-response studies conducted in young (~22 years) and older adults (~75 years) g of protein providing ~10-20 g of essential amino acids Thomas DT et al., J Acad Nutr Diet, 2016, Bauer J et al., JAMDA 2013, Moore DR et al., Am J Clin Nutr, 2009, Witard OC, et al., AM J Clin Nutr, 2013, Yang Y et al., Br J Nutr, 2012, Pennings B et al., Am J Physiol Endocrinol Metab,

26 Considering high quality proteins in diet design Complete: High-quality proteins that provide sufficient amounts of essential amino acids Enables sensible diet design (difficult to construct a low-calorie diet that provides protein content of similar quality with plant foods) Slide adapted with permission from Nancy Rodriguez, PhD, RD 26

27 Protein quality can impact meal planning Some experts suggest aiming for ~2.5g of leucine per meal to help maximize muscle protein synthesis Source of nutritional information: USDA National Nutrient Database for Standard Reference Release 27 Supplement facts panel for generic whey and soy protein isolates 27

28 25g of protein looks different across various foods USDA National Nutrient Database for Standard Reference Release 28 Supplement facts panel for generic whey protein isolate *EAA = Essential Amino Acids; includes Histidine, Isoleucine, Leucine, Lysine, Methionine, Phenylalanine, Threonine, Tryptophan and Valine 28

29 Dairy foods provide high quality protein options Dairy Food Protein Leucine Low-fat Cheese (1 oz) 7 g g* Low-fat Milk (regular or lactose-free dairy milk) (8 oz) 8 g 0.8 g Low-fat Cottage Cheese (4 oz) 14 g 1.4 g Low-fat Greek Yogurt (7 oz) 19 g 1 g Whey Protein Isolate Powder (unflavored) (1 scoop, 22 g) 20 g 2.5 g *Leucine content varies depending on the type of cheese Source of nutritional information: USDA National Nutrient Database for Standard Reference Release 27 29

30 Milk s essential nutrients can be hard to replace Three 8oz servings of milk provides the same level of nutrients found in these foods similar amounts of calcium can be obtained from fortified rice, soy and almond milks, and fortified juices, but absorption of calcium is less efficient from plant beverages...vitamin D and potassium amounts vary across these milk alternatives (DGAC 2015) 30

31 Innovative & practical concept: Essential amino acid density Caloric Density Nutrient Density Essential Amino Acid Density Slide adapted with permission from Nancy Rodriguez, PhD, RD 31

32 Considering essential amino acid density 1 Tbsp peanut butter 6% of all EAA requirements 1 ¼ cup cooked black beans 9% of all EAA requirements 1 1 large egg 17% of all EAA requirements 1 1 ounce cooked chicken breast 17% of all EAA requirements 1 8 ounces milk 22% of all EAA requirements 1 1 scoop whey protein isolate (28g protein) 82% of all EAA requirements 2 Slide adapted with permission from Nancy Rodriguez, PhD, RD *EAA requirements (includes histidine) based on the RDA for Adults (19 years and older). Calculations based on 175lb. adult. *The protein foods group uses ounce-equivalents as a serving, and the low-fat or fat-free dairy group considers 8 ounces of milk a cup-equivalent. 1 Nutritional content taken from the USDA National Nutrient Database for Standard Reference Release 28 2 Nutritional content taken from supplement facts label of generic whey protein isolate 32

33 Current protein intakes in the U.S: Perception vs. reality Aug 2,

34 % kcal There is room to moderately increase protein consumption across all ages in both males and females Men Women AMDR NHANES Age 34

35 Protein: g/day Lowest amount of protein is consumed at breakfast and from snacks Percent of daily protein Men Women Breakfast: 16% Lunch: 28% Dinner: 42% Snacks: 14% Breakfast Lunch Dinner Snacks Daily total: 93.7 g Breakfast Lunch Dinner Snacks Daily total: 66.5 g NHANES

36 Summary Maintaining muscle is important in support of overall health Routine exercise & balanced nutrition are critical for maintaining muscle Protein recommendations: meeting requirements vs. optimizing health outcomes Protein quality: significance to energy efficient and nutrient dense meal plans All protein sources are not equivalent as sources of EAAs Dairy foods and ingredients provide a variety of convenient, nutrient rich and flavorful options to obtain high quality protein There is room for adults to moderately increase their protein intake and/or shift their pattern of intake while still remaining within the AMDR 36

37 Thank You! 37

38 Backup Slides 38