In what timeframe would you expect the results to show a good change with recommended supplementation?
The frequency of ordering blood work depends on an individual's condition and what you are monitoring. Optimal follow-up is vital to optimal health.
The frequency of blood testing would depend on the acuity of an individual’s condition and what condition you are monitoring. In the intensive care unit labs may be drawn at least once per day, in elite athletes they may be drawn weekly, in chronic disease monitoring they may be drawn 2-3 months apart, and routine health checks may only require an annual blood draw.
If you are monitoring a specific condition or set of biomarkers, the frequency of monitoring may vary.
In the example of anemia, or monitoring hemoglobin A1C or CBC, the average lifespan of a red blood cell is 120 days, so re-testing every 4-6 months to see changes would be prudent. This schedule would provide valuable clinical information while minimizing an individual’s need to have their blood drawn, a potentially unpleasant experience for some.
If an individual has blood loss or an acute condition that requires frequent monitoring, labs may need to be drawn more frequently and monitored by a physician.
For many individuals, a 6-month schedule would be an effective tool for monitoring health and response to nutrition therapy. Once someone is stable and healthy, annual monitoring should suffice.
References
Pedlar, Charles R et al. “Blood Biomarker Profiling and Monitoring for High-Performance Physiology and Nutrition: Current Perspectives, Limitations and Recommendations.” Sports medicine (Auckland, N.Z.) vol. 49,Suppl 2 (2019): 185-198. doi:10.1007/s40279-019-01158-x
Sikaris, Kenneth A. “Enhancing the Clinical Value of Medical Laboratory Testing.” The Clinical biochemist. Reviews vol. 38,3 (2017): 107-114.