Most people would not consider our bones are alive, in fact, it is. Every day, bone tissue is continually renewed in our bodies. Our bones consist of mineralised tissue as well as several different varieties of cells embedded in it. Some of these cells make up part of the physical structure of the bone, and others are responsible for renewing and rejuvenating bone. As we get older and bone ages, our bones break down more bone than they can build and put back, thus it may become weak and cracked, needing replacement. It is normal to lose some bone as we age. But, if we do not take it as a serious matter to keep our bones healthy, we can lose too much bone and get osteoporosis. What’s the worst? People may have weak bones and don’t even know it. It is because bone loss often happens over a long period of time and doesn’t hurt. Keeping bone mass at its peak should start as early as a person enters his/her 30s to prevent rapid bone loss when aging hits.