In older people with osteoporosis , higher protein intake ( ≥ 0.8-g/kg body weight/day , i.e. , above the current RDA ) is associated with higher BMD , a slower rate of bone loss , and reduced risk of hip fracture , provided that dietary calcium intakes are adequate .
Intervention with dietary protein supplements attenuate age-related BMD decrease and reduce bone turnover marker levels , together with an increase in IGF-I and a decrease in PTH .
There is no evidence that diet-derived acid load is deleterious for bone health .
Thus , insufficient dietary protein intakes may be a more severe problem than protein excess in the elderly .
A summary of systematic review s and meta-analyses addressing the benefits and risks of dietary protein intakes  for  bone health in adults suggests that dietary protein levels even above the current RDA may be beneficial in reducing bone loss and hip fracture risk , provided calcium intakes are adequate .
Several systematic review s and meta-analyses have addressed the benefits and risks of dietary protein intakes for bone health in adults .
Adequate supplies of dietary protein are required for optimal bone growth and maintenance of healthy bone .
Variation in protein intakes within the “ normal ” range accounts for 2–4 % of BMD variance in adults .
A diet high in protein, dairy, and calcium attenuates bone loss over twelve months of weight loss and maintenance relative to a conventional high-carbohydrate diet in adults.
Weight loss causes  bone mineral loss .  Higher protein diets continue to be criticized for further potential harmful bone effects , including elevated urinary calcium , but may promote bone health if protein sources include dairy . Overweight middle-aged subjects ( n = 130 , 59 males ) were r and omized to a diet providing 1.4 g.kg(-1).d(-1 ) protein and 3 daily servings of dairy ( PRO ) or 0.8 g.kg(-1).d(-1 ) protein and 2 daily servings of dairy ( CARB ) for 4 mo of weight loss plus 8 mo of weight maintenance . Diets prescribed 6276 kJ/d for females and 7113 kJ/d for males . Bone mineral content and density ( BMD ) for whole body ( WB ) , lumbar spine ( LS ) and total hip ( TH ) were measured using dual X-ray absorptiometry , and dietary intake using 3-d weighed food records . Urinary calcium was measured using 24-h collection at 0 and 8 mo for a sub sample ( n = 42 ) . Participants lost body weight ( mean , 95 % CI ) of 8.2 % ( 7.5 - 8.9 % ) at 4 mo , 10.6 % ( 9.5 - 11.8 % ) at 8 mo , and 10.5 % ( 8.9 - 12.0 % ) at 12 mo without differences between groups at any time ( P = 0.64 ) . At 12 mo , PRO BMD was higher by 1.6 % ( 0.3 - 3.0 % ) at WB , 2.1 % ( 0.6 - 3.7 % ) at LS , and 1.4 % ( 0.2 - 2.5 % ) at TH compared with  CARB  .  PRO calcium intake was higher ( PRO : 1140 + /- 58 mg/d , CARB : 766 + /- 46 ; P < 0.01 ) , as was urinary calcium ( PRO : 163 + /- 15 mg/d , CARB : 100 + /- 9.2 ; P < 0.01 ) . A reduced-energy diet supplying 1.4 g.kg(-1).d(-1 ) protein and 3 dairy servings increased urinary calcium excretion but provided improved calcium intake and attenuated bone loss over 4 mo of weight loss and 8 additional mo of weight maintenance
In older people with osteoporosis , higher protein intake ( ≥ 0.8-g/kg body weight/day , i.e. , above the current RDA ) is associated with higher BMD , a slower rate of bone loss , and reduced risk of hip fracture , provided that dietary calcium intakes are adequate .
Intervention with dietary protein supplements attenuate age-related BMD decrease and reduce bone turnover marker levels , together with an increase in IGF-I and a decrease in PTH .
There is no evidence that diet-derived acid load is deleterious for bone health .
Thus , insufficient dietary protein intakes may be a more severe problem than protein excess in the elderly .
A summary of systematic review s and meta-analyses addressing the benefits and risks of dietary protein intakes  for  bone health in adults suggests that dietary protein levels even above the current RDA may be beneficial in reducing bone loss and hip fracture risk , provided calcium intakes are adequate .
Several systematic review s and meta-analyses have addressed the benefits and risks of dietary protein intakes for bone health in adults .
Adequate supplies of dietary protein are required for optimal bone growth and maintenance of healthy bone .
Variation in protein intakes within the “ normal ” range accounts for 2–4 % of BMD variance in adults .