The jury still seems to be out as to what a "normal" level of Serum 25-Hydroxyvitamin D should be. According to the NIH:
"There is considerable discussion of the serum concentrations of 25(OH)D associated with deficiency (e.g., rickets), adequacy for bone health, and optimal overall health, and cut points have not been developed by a scientific consensus process. Based on its review of data of vitamin D needs, a committee of the Institute of Medicine concluded that persons are at risk of vitamin D deficiency at serum 25(OH)D concentrations <30 nmol/L (<12 ng/mL). Some are potentially at risk for inadequacy at levels ranging from 30–50 nmol/L (12–20 ng/mL). Practically all people are sufficient at levels ≥50 nmol/L (≥20 ng/mL); the committee stated that 50 nmol/L is the serum 25(OH)D level that covers the needs of 97.5% of the population. Serum concentrations >125 nmol/L (>50 ng/mL) are associated with potential adverse effects"
According to this <12 ng/mL is deficient, >50 ng/mL is potentially harmful. So pick a number in the middle? I like to keep mine in the mid-forties, I'm comfortable there, I take 5000 iu/day. As with anything the key is not to over do it.
DX Jan '10, at 47
Feb - colon resection - 2/17 nodes
April - liver mets - Stage 4
3 months Folfox chemotherapy
August '10 liver resection and HAI pump
7 months chemo FUDR HAI and Folfiri systemic
NED since August 2010
Last treatment April '11
HAI Pump removed Dec '15