Maintaining healthy bone is a work of a life time.  Bone is the only tissue in the body that has the dynamics to continually replacing itself.   See: http://www.lab.anhb.uwa.edu.au/mb140/moreabout/bonedynamics.html

There are several factors necessary for healthy bone and all, yes all are necessary for healthy bone.  See: https://www.ncbi.nlm.nih.gov/books/NBK45504/

  1. Activity:  Bone responds to forces applied.  This is why as people grow old and less active they have softer bones.  The most vivid example is the osteoporosis that occurred with astranots and long periods of weightlessness.
  2. Calcium:  Calcium is a necessary requirement for healthy bones.  Hopefully it may be in one’s daily diet.  If not, then a supplement may be required.
  3. Vitamin D:  Vitamin D is a requirement of healthy bones.  It may be a supplement and or provided by sunshine.
  4. Hormonal deficiency:  This is common in post menopausal women who lack estrogen.  They often require a supplement for good bone health.

There are other factors not to be overlooked; magnesium and vitamin K.  I make quotes from https://takecareof.com/articles/4-best-vitamins-supplements-bone-health

Magnesium: Magnesium, an essential mineral for the overall health of the body, aids the body in regulating calcium levels. Approximately 50-60% of the body’s magnesium is stored in the skeletal system. Due to its importance to the skeletal system, both structurally and functionally, it cannot be left out of any discussion of bone health.

Like vitamin D, magnesium supports calcium’s functions. Specifically, it is active in the transport of calcium across cell membranes. Additionally, it supports the structural development of new bone tissue.

Magnesium is plentiful in nuts, leafy green vegetables, and beans. If you aren’t regularly eating these foods, consider a magnesium supplement, especially if you consume alcohol or caffeine, which both deplete magnesium levels in the body.

Vitamin K: Vitamin K exists in two forms: vitamin K1 (phylliquinone) and vitamin K2 (menaquinone). Vitamin K2 supports the cardiovascular system. It also acts as a coenzyme for proteins required in bone metabolism.

These findings were expanded upon in a 2013 study that showed vitamin K2 supplements may support bone health in postmenopausal women.