The Association Between Dietary Protein Intake And Bone Mass Accretion In Pubertal Girls With Low Calcium Intakes, British Journal of Nutrition, March 2010
A 5-year study in Beijing, China involving 757 girls, average age of 10 years. The intervention was cows milk for the first 2 years of the study.
"Negative associations were observed between protein intake (55.9–61.0 g/d on average) and BMC accrual at TB, PF or DF (β = − 1.92, − 10.2 or − 4.82, respectively, P < 0.01) after adjustment. When protein intake was considered according to animal or plant food sources, protein from animal foods, particularly meat, had significant negative effects on bone mineral content accrual at DF or PF after adjustment. It was concluded that higher protein intake, especially from animal foods, appeared to have a negative effect on bone mass accrual."The more meat and eggs the girls ate, the lower their bone density.
The recommended protein intake for a 120 pound adult is 44 grams/day. Although some recommend no more than 30 grams/day.
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