Bones have many functions – as well as supporting the body structurally, they also protect our vital organs, allow us to move, are where blood cells are created, and also act as a storage area for minerals. Humans are born with around 270 soft bones, some of which fuse as we grow, leaving us with 206 bones once we reach adulthood. Bones know as living tissue and play a structural role in the body. Because it is a living tissue it continues to be renewed throughout life, with older cells being replaced by new ones.
Bone is made up of a protein matrix strengthened with minerals, particularly calcium and phosphorus. There is a net accretion of calcium in bones during growth. Bone mass increases throughout growth until our early twenties when peak bone mass is achieved. There is then a period of consolidation but, from the age of about 40 years, bone loss exceeds bone formation and mass gradually decreases. Excessive loss of bone tissue leads to osteoporosis, a condition that is characterized by bone fragility and increased risk of bone fracture. Osteoporosis may lead to mobility problems and even death.
It is important to optimize bone mass during growth and to maintain the skeleton during adult life in order to reduce the risk of osteoporosis developing in later life. A number of nutrients play a role in establishing and maintaining healthy bones, in particular, calcium, vitamin D, and vitamin K. An active lifestyle is also important.