http://www.medscape.com/viewarticle/513547 says:
"Direct Effect of Phosphate on Cardiovascular Disease (CVD)"

"Passive Calcium Phosphate Deposition. First among these is a
relatively simple process by which an increase in the serum PO4
concentration results in a proportional increase in the calcium X PO4
product. Eventually, a point is reached that facilitates the passive
precipitation of both calcium and PO4 as a result of its
supersaturation in blood. This mechanism of calcification depends on
the solubility product of calcium and PO4 ions with the concentration
of phosphate the critical factor.[1] According to this concept,
vascular calcification is simply a passive process."

"Active Phosphate Transport. Contrary to this notion are the data that
support a role for an active process that in many respects resembles
bone mineralization and centers around PO4 metabolism. For example, in
studies of cultured smooth muscle cells, inorganic PO4 concentrations
of approximately 4.3 mg/dL lead to the expression of several bone
markers such as osteocalcin, with subsequent mineralization of the
extracellular matrix.[2] Cells that are grown in the presence of
higher inorganic PO4 concentrations show an increased deposition of
calcium into vascular cells.[3] It has also been observed that
hyperphosphatemia promotes the phenotypic conversion of smooth muscle
cells to osteogenic cell types. This has been demonstrated in both
animals[4] and humans,[5] where it is thought to be mediated by a
sodium-dependent PO4 cotransporter that facilitates the entry of
inorganic PO4 into vascular cells."

That leads me to wonder if the dietary intake of phosphate is reduced
will that reduce CVD. Many meats have sodium phosphate added and brown
sodas (colas, Dr. Pepper, and root beer) have phosphoric acid added.

--
  Ron