1. Protein for Healthy Bones
Wendy E. Ward
Professor & Canada Research Chair
Faculty of Applied Health Sciences
All Rights Reserved

2. Outline What is the current recommendation for protein intake?
How to consume?
Current Recommendation (RDA) for Protein Intake
Why is more needed?
Suggested intake
Distribution throughout the day
Source & contribution to overall nutrition
Calcium as a modifier of a beneficial effect
Level of Dietary Protein to Support Muscle & Bone During Aging

3. Outline What is the current recommendation for protein intake?
How to consume?
Current Recommendation (RDA) for Protein Intake
Why is more needed?
Suggested intake
Distribution throughout the day
Is higher protein harmful to bone?
Source & contribution to overall nutrition
Calcium as a modifier of a beneficial effect
Level of Dietary Protein to Support Muscle & Bone During Aging

4. 0.8 g protein/kg body weight/day
Recommended Dietary Allowance (RDA)
0.8 g protein/kg body weight/day
for all ages!

5. 0.8 g protein/kg body weight/day
Recommended Dietary Allowance (RDA)
0.8 g protein/kg body weight/day
for all ages!
For individuals of
60 – 80 kg body weight
48 – 64 g protein/day

6. How to consume 48-64 g protein/day?
’Scoop’ of Whey Protein: 25 g protein, 113 kcal

7. 0.8 g protein/kg body weight/day
Recommended Dietary Allowance (RDA)
0.8 g protein/kg body weight/day
for all ages!
For individuals of
60 – 80 kg body weight
48 – 64 g protein/day

8. 0.8 g protein/kg body weight/day But…..likely higher need due to aging
Recommended Dietary Allowance (RDA)
0.8 g protein/kg body weight/day
for all ages!
For individuals of
60 – 80 kg body weight
48 – 64 g protein/day
But…..likely higher need due to aging

9. Outline What is the current recommendation for protein intake?
How to consume?
Current Recommendation (RDA) for Protein Intake
Why is more needed?
Suggested intake
Distribution throughout the day
Is higher protein harmful to bone?
Source & contribution to overall nutrition
Calcium as a modifier of a beneficial effect
Level of Dietary Protein to Support Muscle & Bone During Aging

10. Why might we need higher levels of dietary protein as we age?
Current Recommendation for Protein
Sarcopenia: loss of muscle mass & function
Ability to absorb and utilize protein is compromised:
↓ protein digestion
↓ absorption of amino acids
(building blocks of protein)
↓ uptake into muscle
With aging, muscle does not respond as effectively to protein
↓ protein synthesis
-Position paper from the PROT-AGE Study Group. JAMDA. 2013:14:
-Recommendations from the ESPEN Expert Group. Clin Nutr. 2014;33:
-Consensus statement of ESCEO. Maturitas. 2014;79:

11. Maintain Muscle Mass & Strength in 20-25 g protein at each meal for an
Current Recommendation for Protein
Suggested Intake……..
Maintain Muscle Mass & Strength in
Healthy Older Adults:
g protein/kg bw/day
20-25 g protein at each meal for an
‘even’ distribution
-Position paper from the PROT-AGE Study Group. JAMDA. 2013:14:
-Recommendations from the ESPEN Expert Group. Clin Nutr. 2014;33:
-Consensus statement of ESCEO. Maturitas. 2014;79:

12. Higher Protein Intake Supports Muscle Mass & Function
Higher protein intake (2-6 year follow-up):
less loss of mid-arm muscle area, lean mass
higher muscle mass, leg lean mass
greater arm & leg strength
function: walk speed (normal, fast)
‘Even’ protein consumption (2-3 year follow-up):
higher lean mass, leg lean mass
greater muscle strength, leg strength
Position paper from the PROT-AGE Study Group. JAMDA. 2013:14:
Recommendations from the ESPEN Expert Group. Clin Nutr. 2014;33:
Consensus statement of ESCEO. Maturitas. 2014;79:

13. Stronger Muscle Benefits Bone Health
BMD, Fracture?
Attenuate loss of muscle mass, strength & performance
Greater walking distance
Reduced risk of falls

14. Stronger Muscle Benefits Bone Health
BMD, Fracture?
Attenuate loss of muscle mass, strength & performance
Greater walking distance
Reduced risk of falls
There may also be direct benefits of protein to bone health

15. Is higher protein harmful to bone?
↑ dietary protein
↑ urinary Ca excretion
↓ bone mineral
↑ risk of fracture
Assuming Ca is from bone….

16. Do higher protein diets adversely affect bone health?
Is higher protein harmful to bone?
↑ dietary protein
↑ Ca absorption
↑ urinary Ca excretion ?
? bone mineral
? risk of fracture

17. Is higher protein harmful to bone?
↑ dietary protein
↑ Ca absorption
↑ urinary Ca excretion
+ direct effect
↑ IGF-1
↑ muscle mass, strength, function
✔️associated with falls ?
? bone mineral
? risk of fracture

18. Protein Supplementation
High Dietary Protein &
Calcium Excretion
Protein Supplementation
Healthy older men & women, > 50 y, n=32
<0.85 g protein/kg or less, <700 mg Ca
low vs. high dietary protein (meat), 0.75 vs.1.6 g/kg
9 week intervention
No increase in calcium excretion or adverse effect
on biochemical markers of bone turnover
Some favourable effects:
↑ IGF-1
↓ N-telopeptide
(Dawson-Hughes et al. JCEM. 2004;89:1169)

19. Protein & Bone Health

20. 2017

21. Two research questions: Effect of high versus low protein intake
2017
Two research questions:
Effect of high versus low protein intake
Is there a benefit of Ca with dietary protein?

22. How do Calcium and Protein work together for bone health?
“Building blocks of bone”
Bone contains matrix and mineral:
Matrix: protein such as collagen
Mineral: such as calcium and other minerals
Mineralization is the incorporation of mineral within the matrix.

23. Two research questions: Effect of high versus low protein intake
2017
Two research questions:
Effect of high versus low protein intake
Is there a benefit of Ca with dietary protein?
16 randomized controlled trials (RCTs)
20 prospective cohort studies
Various outcomes: BMD, fracture, markers
Different skeletal sites

24. Positive trends for high vs. low protein intakes to benefit BMD
2017
FINDINGS:
1. High vs. low intakes:
Positive trends for high vs. low protein intakes to benefit BMD
-spine but not total hip or body, femur neck
No adverse effects on BMD
2. Benefit of protein with Ca?
Evidence not strong, very different study designs
make it difficult to compare findings from the studies

25. Positive trends for high vs. low protein intakes to benefit BMD
2017
Conclusion:
Existing data are not consistent enough to warrant a clinical guideline to recommend that individuals increase their protein intake.
FINDINGS:
1. High vs. low intakes:
Positive trends for high vs. low protein intakes to benefit BMD
-spine but not total hip or body, femur neck
No adverse effects on BMD
2. Benefit of protein with Ca?
Evidence not strong, very different study designs
make it difficult to compare findings from the studies

26. Calcium & Protein

27. Calcium Modulates Association of
Protein & Hip Fracture
Framingham Offspring Cohort
Mean age = 75 years
44 hip fractures over 12 years (10 m, 34 f)
Assessed intakes of protein and calcium using a diet questionnaire (FFQ)
<800 mg Ca/day
T3 vs. T1
(60 vs. 34 g/d)
↑ hip fracture risk
>800 mg Ca/day
(76 vs. 48 g/d)
↓ hip fracture risk
(Sahni et al. JBMR. 2010;25:2770)

28. Calcium Modulates Association of
Protein & Hip Fracture
Framingham Offspring Cohort
Mean age = 75 years
44 hip fractures over 12 years (10 m, 34 f)
Assessed intakes of protein and calcium using a diet questionnaire (FFQ)
<800 mg Ca/day
Highest vs. Lowest Intakes
(60 vs. 34 g/d)
↑ hip fracture risk
>800 mg Ca/day
(76 vs. 48 g/d)
↓ hip fracture risk
(Sahni et al. JBMR. 2010;25:2770)

29. Calcium Modulates Association of
Protein & Hip Fracture
Framingham Offspring Cohort
Mean age = 75 years
44 hip fractures over 12 years (10 m, 34 f)
Assessed intakes of protein and calcium using a diet questionnaire (FFQ)
<800 mg Ca/day
Highest vs. Lowest Intakes
(60 vs. 34 g/d)
↑ hip fracture risk
>800 mg Ca/day
(76 vs. 48 g/d)
↓ hip fracture risk
(Sahni et al. JBMR. 2010;25:2770)

30. Source of Protein

31. Does Source of Protein Matter?
ANIMAL
dairy, chicken,
pork, beef, fish
PLANT
legumes (soy),
peas, beans, lentils, quinoa
Protein:Energy, Fiber, Fat profile, Bioactives
*we eat foods, not individual nutrients*

32. Equal amounts of dietary protein from animal vs. plant sources
2018
Equal amounts of dietary protein from
animal vs. plant sources

33. Equal amounts of dietary protein from animal vs. plant sources
2018
Equal amounts of dietary protein from
animal vs. plant sources
Outcomes:
1 year: BMD (total body, hip, spine)
6 months: bone formation or resorption markers
7 randomized controlled trials

34. Equal amounts of dietary protein from animal vs. plant sources
2018
Equal amounts of dietary protein from
animal vs. plant sources
Outcomes:
1 year: BMD (total body, hip, spine)
6 months: bone formation or resorption markers
7 randomized controlled trials
Conclusion: No advantage of either soy or animal protein (BMD, bone markers)

35. Quality of evidence low Soy as supplement, not whole food
2018
CONSIDERATIONS:
Quality of evidence low
Soy as supplement, not whole food
Low levels of plant protein
Future study: other plant & animal sources
(legumes, beans, quinoa, pea, egg)
Equal amounts of dietary protein from
animal vs. plant sources
Outcomes:
1 year: BMD (total body, hip, spine)
6 months: bone formation or resorption markers
7 RCTs
Conclusion: No advantage of either soy or animal protein (BMD, bone markers)

36. Foods are more than protein……
Protein Source
Foods are more than protein……
ANIMAL
dairy, chicken,
pork, beef, fish
PLANT
legumes (soy),
peas, beans, lentils, quinoa
Protein:Energy, Calcium, Vitamin D,
Fiber, Fat profile, Bioactives

37. Summary Current RDA for Protein
0.8 g protein/kg body weight/day
Food sources
Current RDA for Protein
Aging increases the need for more dietary protein
1 g protein/kg body weight/day
Higher intakes support muscle mass and strength; stronger muscle may protect bone from fracture
Some evidence for bone health directly
Even distribution of protein (muscle)
Source: future study needed Consider other nutrients in a food.
Importance of adequate Ca for bone at higher protein intakes
Level of Dietary Protein to Support Muscle & Bone During Aging

38. Protein for Healthy Bones
Thank you for watching.