A coronary CT angiogram uses contrast-enhanced CT imaging to visualize coronary artery plaque, stenosis, and calcium scoring. Learn what the test measures, how to read results, and when clinicians order it.
Corticosteroids, thyroid hormones, and other medications can shift cystatin C levels independently of kidney function. Learn which drugs interfere, what normal ranges look like, and how clinicians adjust for medication effects.
Learn what cystatin C measures, what normal ranges look like, and the clinical strategies backed by research to improve your cystatin C level and protect kidney function.
Learn the difference between a standard-reference 'normal' cystatin C result and a functionally optimal level. Includes clinical ranges, eGFR implications, and evidence-based strategies to improve kidney biomarkers.
A guide to the blood tests, hormone panels, and metabolic markers that should accompany a DEXA body composition scan for complete clinical context.
Understand why standard DHEA-S reference ranges may not reflect your best health. Learn the difference between lab-normal and clinically optimal DHEA-S, plus how to raise or lower levels safely.
Learn how DUTCH test results directly alter hormone therapy decisions, including HRT dosing, cortisol management, and metabolite-driven protocol adjustments.
Learn when to order the DUTCH (Dried Urine Test for Comprehensive Hormones) test, what it measures, how results compare to serum panels, and which clinical scenarios benefit most from urinary hormone metabolite testing.
Certain medications can artificially raise or lower your eGFR result without changing actual kidney function. Learn which drugs distort eGFR, why they do it, and how clinicians should adjust.
Learn when to order an epigenetic age (DNAm) test, what the results mean, how GrimAge and Horvath clocks work, and how to lower your biological age through evidence-based interventions.
What ESR measures, what counts as a normal range, and which lifestyle changes and medical treatments have actually been shown to move erythrocyte sedimentation rate, with the limits of that evidence made explicit.
Understand the difference between standard lab reference ranges and functional optimal levels for estrone (E1), the dominant estrogen after menopause. Includes clinical ranges, interpretation guidance, and actionable next steps.
Learn what your fasting glucose number means, how to read normal vs. abnormal ranges, and what to do if your result is high or low. prepared by the HealthRX.com Editorial Team.
Your fasting glucose may be 'normal' but not optimal. Learn the difference between standard lab reference ranges and functional medicine targets, what the research says, and how to act on your results.
Learn when to order a fasting glucose test, what normal ranges mean, and how this simple blood draw guides diabetes screening, GLP-1 therapy, and metabolic risk assessment.
Learn what your fasting insulin level means, the normal range, and what high or low values signal about metabolic health. prepared by the HealthRX.com Editorial Team.
Your fasting insulin may be 'normal' but not optimal. Learn the difference between standard lab ranges and functional targets, what high or low levels mean, and how to move toward metabolic health.
A clinical guide to fasting insulin testing, including what the test measures, normal ranges, how to interpret high or low results, and evidence-based strategies to improve insulin levels.
Fasting triglycerides guide treatment: under 150 mg/dL is normal, 150-499 needs lifestyle or meds, 500+ requires urgent therapy to prevent pancreatitis.
A guide to raising or lowering ferritin using diet, supplementation, phlebotomy, and lifestyle changes, backed by clinical trials and society guidelines.
Normal ferritin is 30 to 300 ug/L in men and 10 to 200 ug/L in women, but context matters. See what low, high, and borderline results actually mean.
Normal ferritin runs 12 to 300 ng/mL, but functional optimal is 40 to 200 ng/mL. See target ranges by sex and why symptoms can persist within normal.
A clinical guide to the lab tests you should pair with ferritin, including iron panel, CBC, CRP, transferrin saturation, and more, to accurately diagnose iron deficiency, overload, or inflammation.
Learn what your FibroScan score means, how liver stiffness maps to fibrosis stages F0 through F4, what CAP scores reveal about steatosis, and when to act on abnormal results.
A clinician-informed guide to the laboratory panels and imaging studies that pair with FibroScan (VCTE) for accurate MASLD staging, fibrosis tracking, and treatment decisions.
FibroScan uses vibration-controlled transient elastography (VCTE) to measure liver stiffness and steatosis. Learn what the results mean, normal ranges, and how scores guide MASLD staging and treatment decisions.
A clinical guide to vibration-controlled transient elastography (VCTE / FibroScan), covering when to order the test, how to interpret results, normal ranges, and its role in MASLD staging and treatment decisions.
Methotrexate, phenytoin, valproic acid, sulfasalazine, trimethoprim and metformin can skew folate results. See which drugs, by how much, and when to retest.
A folate level of 5.9 ng/mL is generally sufficient, above the common 3 ng/mL cutoff. Learn how serum and RBC folate together show true status.
RBC folate 140-628 ng/mL is normal, but 500+ ng/mL supports methylation and homocysteine control, especially with MTHFR variants. See serum ranges too.
A clinical guide to the labs you should pair with serum and RBC folate testing, including vitamin B12, homocysteine, MMA, CBC, and iron studies.
Learn what your % free PSA result means, what ranges suggest benign vs. concerning findings, and how this ratio helps guide prostate cancer screening decisions.
Learn when clinicians order the % free PSA test, what the results mean for prostate cancer risk stratification, and how to interpret your ratio in context.
Dozens of common medications can falsely raise or lower your Free T3 result. This clinical guide lists every major drug class that interferes with Free T3 testing, explains the mechanisms, and tells you how to get an accurate reading.
Your Free T3 level directly shapes medication choices, dosing adjustments, and whether your provider adds T3 therapy. Learn what your result means for your specific treatment plan.
Learn when to order a free T4 test, what normal levels mean, and how this thyroid marker guides diagnosis and treatment of hypo- and hyperthyroidism.
Clinically supported strategies to raise free testosterone, including lifestyle changes, supplements with real trial data, and when TRT becomes the right option.
Learn which lab tests to pair with FSH for accurate diagnosis of menopause, fertility issues, and pituitary disorders. Evidence-based guide with specific panels and clinical rationale.
Learn what your galectin-3 level means for heart health, normal ranges by assay, what high and low values indicate, and evidence-based ways to improve your result.
Learn what your Galectin-3 blood test means, the difference between standard reference ranges and functional optimal levels, and evidence-based strategies to lower elevated Galectin-3 for heart and metabolic health.
Learn which lab tests to pair with Galectin-3 for accurate cardiac fibrosis assessment, heart failure prognosis, and metabolic risk stratification.
Learn when clinicians order a galectin-3 blood test, what normal and abnormal levels mean, how results guide heart failure prognosis, and evidence-based ways to manage elevated galectin-3.
A guide to interpreting and improving organic acids urine test markers, covering B-vitamin optimization, mitochondrial support, gut dysbiosis correction, and detoxification pathways.
A clinical guide to ordering urine organic acids testing, including indications, marker interpretation, normal ranges, and how results guide nutritional and metabolic interventions.
Dozens of common medications can raise or suppress GGT levels, turning a routine liver panel into a diagnostic puzzle. Learn which drugs distort GGT, by how much, and what to do about it.
Learn which lab tests to pair with GGT (gamma-glutamyl transferase) for accurate diagnosis of liver disease, biliary obstruction, alcohol use, and oxidative stress.
Gamma-glutamyl transferase (GGT) is a liver enzyme that reflects biliary function, alcohol exposure, and oxidative stress. Learn what GGT measures, normal ranges, and what abnormal results mean.
Learn how GH stimulation test results guide diagnosis and treatment of growth hormone deficiency, including peak cutoffs, dosing decisions, and monitoring protocols.
Learn what the GH stimulation test measures, what normal and abnormal results mean, and clinically validated strategies to raise growth hormone levels backed by endocrine guidelines and peer-reviewed trials.
A clinical guide to the labs you should pair with a GH stimulation test, including IGF-1, thyroid panel, cortisol, prolactin, and metabolic markers, with Endocrine Society guideline references.
GHD is confirmed when peak GH falls below 10 ng/mL (children) or 3 ng/mL on ITT (adults) across two provocative tests. See cutoffs and agents.
Learn how your ghrelin level shapes GLP-1 dosing, appetite management, and metabolic therapy decisions. Includes normal ranges, clinical thresholds, and actionable next steps.
Learn what ghrelin is, what your level means, and the proven dietary, sleep, exercise, and pharmacologic strategies that move ghrelin toward its optimal range.
Learn what your ghrelin lab result actually means. Compare standard reference ranges with functional optimal targets, and understand how GLP-1 therapy, bariatric surgery, and lifestyle factors shift this hunger hormone.
Learn what a ghrelin blood test measures, what normal ghrelin levels look like, and how this hunger hormone connects to GLP-1 therapy, weight regulation, and metabolic health.
Learn what your GIP (gastric inhibitory polypeptide) blood test result means, including normal ranges, high and low values, and what GIP levels reveal about metabolic health and incretin function.
Compare standard reference ranges for GIP (gastric inhibitory polypeptide) with functional optimal levels. Learn what high or low GIP means, how GIP relates to tirzepatide and incretin therapy, and when to test.
Learn when clinicians order GIP (gastric inhibitory polypeptide) testing, what normal ranges look like, and how GIP levels connect to obesity, type 2 diabetes, and tirzepatide therapy.
Which medications interfere with the GLP-1 (active) assay? A clinical guide to drugs that raise, lower, or invalidate active GLP-1 levels, plus how to interpret results if you cannot pause therapy.
Learn what your GLP-1 (active) lab result means, what normal ranges look like, and what high or low levels may indicate for metabolic health.