Calcium and vitamin D
– Role in Musculoskeletal Health
Bess Dawson-Hughes, M.D.
How to understand the absorption
of calcium correctly？
 Calcium
Ca intake  absorption   Vitamin D

 Ca++
 Muscle str.

 PTH
 Falls

Bone remodeling


Bone loss
 Fracture risk
Mechanisms of Intestinal Calcium Absorption
Hoenderop J, et al. Physiol Rev. 2005;85:373-422.
Bullamore R. Lancet 1970; 2: 535-7.
What is the calcium intake that
leads to maximal calcium
retention in bone?
Forbes, 1979
% Maximal retention
300
300
200
200
100
100
0
0
-100
-100
-200
0
Linda and George McCabe,
Purdue University, with
permission
500
1000
1500
2000
Intake (mg/day)
2500
Intestinal Absorption of Calcium
from Different Calcium Salts
 Calcium absorption from different calcium salts were similar to whole
milk
Net Calcium absorption（%）
45
40
39
32
35
32
30
30
31
27
25
20
15
10
5
0
Carbonate
Lactate
Acetate
Citrate
Gluconate
Whole milk
Sheikh MS, et al. N Eng J Med,1987,317(9):532-6
Calcium Absorption in Relation to Dose
Harvey JA, et al. J Bone Miner Res 1988; 3: 253-8.
Calcium Absorption in Relation to
Gastric Acid Secretion
Bo-Linn GW, et al. J Clin Invest,1984,73:640-7.
Calcium Absorption in Relation to Meal
Heaney RP, et al. Am J Clin Nutr 1989; 49: 372-6.
Effect of Oral Amino Acids
on Absorption of Calcium
Civitelli R et al. Nutrition 1992; 8(6):400-405
Amino acid chelated calcium &
Carbonate calcium
Search: MEDLINE 1999-2003
Search: MEDLINE 2004-2006
•
•
•
•
•
•
•
•
•
•
•
•
•
•#1
0
Osteoform
•#2
147398
amino
•#3
288313
acid
•#4
345
chelated
•#5
64534
calcium
•#6
0
calcium
amino acid chelated
•#7
2473
carbonate
•#8
64534
calcium
•#9
855
carbonate calcium
•
#1
#2
#3
#4
#5
#6
#7
#8
#9
#10
#11
0
30345
0
64802
136334
172
30345
0
1531
30345
583
osteoform
calcium
osteoform and calcium
amino
acid
chelated
calcium
amino acid chelated calcium
carbonate
calcium
carbonate calcium
Lead Content of Calcium Supplements
Supplement
category
Lead content, g/
800 mg calcium
Refined
0.92  0.56
Dolomite
4.17  2.02
Natural source
6.05  4.63
Bone meal
Milk
11.33  12.46
0.71  0.32
Borgoin BP, et al. Am J Pub Health 1993.
Effect of Increasing Calcium Intake on
PTH and Bone Turnover in Women
Elderly
Normal Ca
High Ca
Young
Calcium Intake
(mg/d)
PTH (pmol/L)
813
2,414
918
3.41a
2.18
2.01
Urine pyridinoline/Cr
51.7b
43.1
43.7
a Differs from other groups, p < 0.001
b Differs from other groups, p < 0.05
McKane WR et al. J Clin Endocrinol Metab 1996; 81(5):1699-1703.
Calcium Supplementation for the Prevention of
Postmenopausal Osteoporosis：a meta-analysis
Weighted mean difference for lumbar spine after treatment with calcium at 2 yr
Calcium supplementation in women older than 45 yr with absence of menses
for a minimum of 6 months; Treatment with doses of calcium at least 400
mg/d. The maintenance dose of vitamin D was no more than 400 IU/d
Shea B, et al. Endocrine Rev . 2002,23(4):552-559.
Calcitonin, Calcium and Vertebral
Fracture Risk – MEDOS Study
1
*
0.5
0.78
0.82
0.63
Calcitonin
Calcium
Ca + Calcitonin
0
*P=0.01
Kanis JA. Br Med J 1992; 305; 1124-28.
Fracture Prevention Trials: Calcium
and Vitamin D Use and Results
Drug/Study
Alendronate
Liberman ‘95
Black ‘96
Cummings ‘98
Risedronate
Harris ‘99
Raloxifene
Ettinger ‘99
Ca, mg/d
Vit D, IU/d
Fracture risk
reduction (RR)
500
500*
0
250
0.5
0.5
500*
250
0.6
500†
0.6
400-600
0.7
1,000
500
* If dietary calcium < 1,000 mg
†
If 25(OH)D level < 40 nmol/L
Calcium Intake in
Elderly Chinese Women
Vegetarian
(N=179)
81.3
Omnivore
(N=250)
70.7
Calcium, mg/1000 kcal
328
221
Potassium, mg/1000 kcal
914
783
Age
Woo J et al. Age and Ageing 1998; 27:455-461.
Magnesium – Research Progress
• Mg depletion studies have been done in rats.
• Several epidemiologic studies have found
positive associations between magnesium
intake and bone mass and negative
associations with diabetes and stroke.
Magnesium Depletion and the
Skeleton in Rats
Diet % Nutrient
Requirement
Outcome
50a
↓ trabec vol, ↑osteoclast #
25b
also ↑TNF-alpha
10c
also ↑TNF-alpha
a Rude
R. OI 2006; on-line.
R. Bone 2005; 37:211-219.
c Rude R. J Nutr 2004; 134:79-85.
b Rude,
Magnesium Intake – Associations
with Diabetes and Stroke
Diabetesa
In >100,000 subjects followed for 12 to 18 yrs:
RR 0.66 [0.60 –
High vs. low quintile
0.73]
Strokeb
In 43,738 men followed for 8 yrs:
High vs. low quintile
a
RR 0.62 [0.43, 0.88]
Lopez-Ridaura R et al. Diabetes Care 2004; 27(1):134-140.
b Ascherio A et al. Circulation 1998; 98(12):1198-204.