Thursday, January 15, 2009

New Frontiers in Bone Health

Bone loss has been traditionally understood as being an issue of lack of calcium, vitamin D, and minerals. While these factors certainly play an important role in why people develop osteoporosis, it is not the only factor to consider. In fact, after age 50 it may be secondary to other more profound issues.

Consider that there is a distinct and important difference between bone density (mineralization) and bone matrix quality. The matrix of the bone is a mesh of collagen microfibers that can be compared to the iron rods that provide structure and support to the pavement in highways. Without the iron mesh, the pavement would deteriorate very quickly under all the wear and tear of the traffic. The mesh of collagen fibers is what provides bone their structural strength and is what minerals attach to.

A DEXA scan, therefore, may not be the most accurate way to assess bone health because a DEXA only looks at bone density, or the minerals that are attached to the matrix. A DEXA cannot provide any information on what is underneath the surface of the bones, thereby providing little or no information about the actual strength of the bones and the quality of the matrix.

In consideration of this fact, it becomes necessary to not only provide minerals and protein for support of bone density, but also provide nutritive substances that will address the quality and structure of the bones.

A New Approach to Bone Support
Before the age of 50, give or take, estrogen is adequate and thus the equilibrium between bone formation and bone resorption is intact. As estrogen declines, however, that equilibrium begins to uncouple, and bone resorption speeds up, thereby causing a faster rate of bone turnover that the formation process cannot keep up with. As a result, bone matrix begins to weaken first, and eventually bone density – that which is visible on a DEXA scan – begins to be effected as well as minerals no longer have an adequate structure to attach themselves. So by the time bone loss begins to appear on a DEXA scan, bone matrix has already been significantly compromised.

It becomes necessary then, to address the uncoupling of bone formation vs. bone resorption.

A 2008 randomized placebo-controlled study at the Functional Medicine Research Center on 76 menopausal women was performed to assess the effectiveness of a non-calcium containing nutritional formula on various markers of bone health, including bone breakdown, bone remodeling, and bone formation. The formula contained reduced iso-alpha acids from hops, berberine, vitamin D3, and vitamin K1. The berberine and hops extracts were used for their effects on modulating proinflammatory signals (NF-kB, RANK, RANKL-mediated TRAP activity) and modifying the expression of certain protein kinases (GSK-3). This strategy has a quieting effect on osteoclast activity,thus creating a better balance between bone formation and bone resorption. Vitamin K promotes metabolism of bone proteins crucial to bone quality and the support of axial and peripheral bone mass. Vitamin D promotes calcium absorption and the process of bone mineralization, as well as supports bone remodeling by modulating inflammatory signals.

In the 14-week trial using 2 per day of the nutritional formula, bone turnover as measured by osteocalcin significantly slowed in the treatment group trending toward youthful levels. Osteocalcin increased in the placebo group. Likewise, all other measurements of bone matrix quality, including IGF-1 and P1NP (bone formation), and NTx (bone resorption), all improved significantly with the treatment group, whereas the placebo group worsened.

This approach is most appropriate for women with low estrogen levels due to menopause, hysterectomy, or any other condition resulting in low estrogen. It is best combined with substances rich in collagen protein, calcium, bone growth factors, and other minerals such as microcrystalline hydroxyapatite concentrate (MCHC) so as to address both factors of bone health – bone density and bone matrix quality. Women who have adequate estrogen would probably be best suited to concentrate on the MCHC approach, and add the berberine and hops complex as they approach the menopausal years.

Happily, there is now an approach that shows promise in addressing a largely overlooked factor in bone health where there was none before.