укрепване на костите bone density begins to decline Calcium and bones pengukuhan tulang National Institutes of Health întărirea oaselor not made naturally in the body bone density begins to decline calcium bone density begins to decline not made naturally in the body Medline Plus: Calcium and Bones (Calcio y huesos) le renforcement des os გაძლიერება ძვლები not made naturally in the body pagpapalakas ng mga buto fortalecimento dos ossos укрепление костей გაძლიერება ძვლები fortalecimiento de los huesos 骨の強化 http://www.nlm.nih.gov/medlineplus/ency/article/002062.htm Stärkung der Knochen versterking van bene हड्डियों को मजबूत बनाने के strengthening of bones