https://libby.health/guides Plain-English guides to your lab results — how to read your blood work, understand individual markers, and track what matters over time. en-us Wed, 11 Nov 2026 00:00:00 GMT https://libby.health/guides/24-hour-urine-protein https://libby.health/guides/24-hour-urine-protein Wed, 11 Nov 2026 00:00:00 GMT A 24-hour urine protein test adds up the protein you lose in a day. How to collect it, what's normal, the nephrotic range, and what it means in pregnancy. 24-hour urine protein proteinuria kidney pregnancy lab results biomarker guides https://libby.health/guides/acth https://libby.health/guides/acth Wed, 11 Nov 2026 00:00:00 GMT ACTH is the pituitary signal that tells your adrenals to make cortisol. Here's a normal morning level, what high and low results mean, and when it's urgent. ACTH adrenal glands pituitary hormones lab results biomarker guides https://libby.health/guides/aldosterone https://libby.health/guides/aldosterone Wed, 11 Nov 2026 00:00:00 GMT Aldosterone controls salt and potassium. See normal levels, how to read it with renin, what a high ratio means, and who should be screened. aldosterone renin primary aldosteronism high blood pressure biomarker guides https://libby.health/guides/ammonia https://libby.health/guides/ammonia Wed, 11 Nov 2026 00:00:00 GMT Ammonia is a waste product your liver turns into urea. Here's the normal range, what raises it, how to read it with other tests, and when it's urgent. ammonia hyperammonemia lab results biomarker guides https://libby.health/guides/anti-ccp-antibodies https://libby.health/guides/anti-ccp-antibodies Wed, 11 Nov 2026 00:00:00 GMT Anti-CCP is the most specific blood test for rheumatoid arthritis. What's normal, what a positive means, why the level matters, and when to get care. anti-CCP rheumatoid arthritis autoimmune lab results biomarker guides https://libby.health/guides/anti-factor-xa-activity https://libby.health/guides/anti-factor-xa-activity Wed, 11 Nov 2026 00:00:00 GMT Anti-Xa measures how much heparin or an Xa-blocking pill is working in your blood. The targets by drug, why draw timing matters, and when to act. anti-Xa heparin blood thinners lab results biomarker guides https://libby.health/guides/antinuclear-antibodies https://libby.health/guides/antinuclear-antibodies Wed, 11 Nov 2026 00:00:00 GMT A positive ANA is common in healthy people. Here's what your titer and pattern mean, which follow-up antibodies matter, and when a result needs prompt care. ANA antinuclear antibodies autoimmune lupus lab results biomarker guides https://libby.health/guides/band-neutrophils https://libby.health/guides/band-neutrophils Wed, 11 Nov 2026 00:00:00 GMT Bands are young neutrophils. Here's what a normal band count is, what a left shift means, why labs disagree on bands, and when high bands are urgent. band neutrophils left shift CBC lab results biomarker guides https://libby.health/guides/base-excess https://libby.health/guides/base-excess Wed, 11 Nov 2026 00:00:00 GMT Base excess shows the metabolic side of your blood's acid balance. Here's the normal range, what a negative or positive result means, and when it's urgent. base excess blood gas acid-base balance lab results biomarker guides https://libby.health/guides/basophil-percentage https://libby.health/guides/basophil-percentage Wed, 11 Nov 2026 00:00:00 GMT Basophils are about 1% of white cells, so the percentage is noisy. What's normal, why % and count disagree, and when a lasting rise matters. basophils basophil percentage complete blood count white blood cells lab results biomarker guides https://libby.health/guides/beta-hydroxybutyrate https://libby.health/guides/beta-hydroxybutyrate Wed, 11 Nov 2026 00:00:00 GMT BHB is the main ketone in your blood. Here's the normal range, what ketosis levels look like, how to tell diet ketosis from DKA, and when a high BHB is urgent. beta-hydroxybutyrate ketones lab results biomarker guides https://libby.health/guides/blood-gas-pco2 https://libby.health/guides/blood-gas-pco2 Wed, 11 Nov 2026 00:00:00 GMT pCO2 shows how well your breathing clears carbon dioxide. Here's the normal range, what high and low results usually mean, and when a result is urgent. pCO2 blood gas lab results biomarker guides https://libby.health/guides/blood-gas-ph https://libby.health/guides/blood-gas-ph Wed, 11 Nov 2026 00:00:00 GMT Blood pH is normally 7.35 to 7.45. Here's what a low or high result usually means, how to read it with pCO2 and bicarbonate, and when it's urgent. blood pH blood gas acid-base lab results biomarker guides https://libby.health/guides/blood-gas-po2 https://libby.health/guides/blood-gas-po2 Wed, 11 Nov 2026 00:00:00 GMT pO2 is the oxygen pressure in your arterial blood: the normal range, what a low result means, how to read it with its neighbors, and when it's urgent. pO2 PaO2 blood gas oxygen lab results biomarker guides https://libby.health/guides/blood-type-abo-rh https://libby.health/guides/blood-type-abo-rh Wed, 11 Nov 2026 00:00:00 GMT Your blood type is two results, ABO group and Rh factor. What each type means, how common it is, why labs recheck it, and why Rh matters in pregnancy. blood type ABO blood group Rh factor pregnancy lab results biomarker guides https://libby.health/guides/carboxyhemoglobin https://libby.health/guides/carboxyhemoglobin Wed, 11 Nov 2026 00:00:00 GMT Carboxyhemoglobin (COHb) is the share of your hemoglobin carrying carbon monoxide. Normal and smoker levels, CO poisoning signs, and when it's urgent. carboxyhemoglobin COHb carbon monoxide lab results biomarker guides https://libby.health/guides/direct-antiglobulin-test https://libby.health/guides/direct-antiglobulin-test Wed, 11 Nov 2026 00:00:00 GMT The direct Coombs test finds antibody or complement stuck to your red cells. What IgG vs C3d means, why positives without hemolysis are common, when to act. direct antiglobulin test Coombs test hemolysis lab results biomarker guides https://libby.health/guides/direct-bilirubin https://libby.health/guides/direct-bilirubin Wed, 11 Nov 2026 00:00:00 GMT Direct bilirubin is the form your liver has already processed. Normal levels, why it runs high, how to read it with ALT and ALP, and when it's urgent. direct bilirubin bilirubin liver tests lab results biomarker guides https://libby.health/guides/eosinophil-percentage https://libby.health/guides/eosinophil-percentage Wed, 11 Nov 2026 00:00:00 GMT Eosinophil % is the share of your white cells that are eosinophils. Here's a normal %, why a high one can mislead, and when to read the count instead. eosinophils complete blood count white blood cells lab results biomarker guides https://libby.health/guides/factor-viii-activity https://libby.health/guides/factor-viii-activity Wed, 11 Nov 2026 00:00:00 GMT Factor VIII helps your blood clot. What a normal level is, how low levels grade hemophilia A, and what a high level means for blood-clot risk. factor VIII hemophilia coagulation lab results biomarker guides https://libby.health/guides/fibrinogen https://libby.health/guides/fibrinogen Wed, 11 Nov 2026 00:00:00 GMT Fibrinogen is a clotting protein that rises with inflammation. The normal range, what optimizers aim for, why it runs high or low, and when it's urgent. fibrinogen clotting inflammation lab results biomarker guides https://libby.health/guides/g6pd-activity https://libby.health/guides/g6pd-activity Wed, 11 Nov 2026 00:00:00 GMT G6PD shields red cells from oxidant damage. What low, intermediate and normal results mean, why women vary, and why a test after hemolysis can mislead. G6PD G6PD deficiency hemolysis lab results biomarker guides https://libby.health/guides/haptoglobin https://libby.health/guides/haptoglobin Wed, 11 Nov 2026 00:00:00 GMT Haptoglobin mops up hemoglobin from broken red cells. What's normal, why it runs low or high, how to read it with LDH and bilirubin, and when to worry. haptoglobin hemolysis anemia lab results biomarker guides https://libby.health/guides/hcg https://libby.health/guides/hcg Wed, 11 Nov 2026 00:00:00 GMT hCG is the pregnancy hormone. Here's a normal level outside pregnancy, how fast it rises, why it can run high, and when a result is urgent. hCG pregnancy hormones lab results biomarker guides https://libby.health/guides/hemoglobin-a-fraction https://libby.health/guides/hemoglobin-a-fraction Wed, 11 Nov 2026 00:00:00 GMT Hemoglobin A is the main adult hemoglobin, usually 95–98% of the total. How the test works, and what a lower share means, from carrier traits to transfusion. hemoglobin A hemoglobin electrophoresis lab results biomarker guides https://libby.health/guides/hemoglobin-a2-fraction https://libby.health/guides/hemoglobin-a2-fraction Wed, 11 Nov 2026 00:00:00 GMT HbA2 is a minor adult hemoglobin. Here's the normal range, why above 3.5% points to beta-thalassemia trait, and what else can push it up or down. hemoglobin A2 thalassemia hemoglobin electrophoresis lab results biomarker guides https://libby.health/guides/hemoglobin-f-fraction https://libby.health/guides/hemoglobin-f-fraction Wed, 11 Nov 2026 00:00:00 GMT Hemoglobin F is the hemoglobin you made before birth. Normal levels by age, why it runs high in HPFH and thalassemia, and why more helps in sickle cell. fetal hemoglobin HbF hemoglobin electrophoresis thalassemia sickle cell disease lab results biomarker guides https://libby.health/guides/hemoglobin-s-fraction https://libby.health/guides/hemoglobin-s-fraction Wed, 11 Nov 2026 00:00:00 GMT Hemoglobin S (HbS) percentage is the share of your hemoglobin that is the sickle form. What 0%, under 40% and over 50% mean, and the 30% target. hemoglobin S sickle cell trait hemoglobin electrophoresis lab results biomarker guides https://libby.health/guides/immature-reticulocyte-fraction https://libby.health/guides/immature-reticulocyte-fraction Wed, 11 Nov 2026 00:00:00 GMT IRF is the share of your reticulocytes that are brand new. Ranges by analyzer, what high and low mean, and how it flags marrow recovery after chemo. immature reticulocyte fraction IRF reticulocytes bone marrow lab results biomarker guides https://libby.health/guides/indirect-bilirubin https://libby.health/guides/indirect-bilirubin Wed, 11 Nov 2026 00:00:00 GMT Indirect bilirubin is bilirubin before the liver processes it. Normal ranges, why it runs high (usually Gilbert syndrome), its neighbors and when it's urgent. indirect bilirubin bilirubin lab results biomarker guides https://libby.health/guides/ldl-particle-number https://libby.health/guides/ldl-particle-number Wed, 11 Nov 2026 00:00:00 GMT LDL-P counts the LDL particles in your blood. Here's a normal and optimal level, why it runs high when LDL cholesterol looks fine, and how it ties to ApoB. LDL-P LDL particle number cholesterol heart health lab results biomarker guides https://libby.health/guides/lead https://libby.health/guides/lead Wed, 11 Nov 2026 00:00:00 GMT A blood lead test shows recent lead exposure. Here are the CDC and workplace thresholds, the common sources, what low levels are linked to, and when to retest. lead blood lead heavy metals lab results biomarker guides https://libby.health/guides/leptin https://libby.health/guides/leptin Wed, 11 Nov 2026 00:00:00 GMT Leptin is made by fat cells, so it tracks body fat and runs higher in women. What's normal, what leptin resistance means, and when the test matters. leptin leptin resistance hormones lab results biomarker guides https://libby.health/guides/lymphocyte-percentage https://libby.health/guides/lymphocyte-percentage Wed, 11 Nov 2026 00:00:00 GMT Your lymphocyte percentage is a share of your white count. Here's the normal range, why it can look off when the count is fine, and when it matters. lymphocyte percentage lymphocytes CBC differential lab results biomarker guides https://libby.health/guides/mercury https://libby.health/guides/mercury Wed, 11 Nov 2026 00:00:00 GMT Blood mercury mostly tracks the fish you ate in recent weeks; urine tracks vapor and inorganic mercury. Typical U.S. levels, action levels, and when to worry. mercury heavy metals lab results biomarker guides https://libby.health/guides/methemoglobin https://libby.health/guides/methemoglobin Wed, 11 Nov 2026 00:00:00 GMT Methemoglobin is hemoglobin that holds no oxygen. Here's the normal level, what raises it, why pulse oximeters misread it, and when a high level is urgent. methemoglobin methemoglobinemia blood gas lab results biomarker guides https://libby.health/guides/monocyte-percentage https://libby.health/guides/monocyte-percentage Wed, 11 Nov 2026 00:00:00 GMT Monocyte percentage is the share of your white cells that are monocytes. Here's the normal range, why it can run high while the count is fine, and when to act. monocyte percentage monocytes white blood cell differential biomarker guides https://libby.health/guides/neutrophil-percentage https://libby.health/guides/neutrophil-percentage Wed, 11 Nov 2026 00:00:00 GMT Neutrophil % is the share of your white cells that are neutrophils. The normal range, why it runs high or low, the count to check, and what NLR adds. neutrophil percentage neutrophils neutrophil-to-lymphocyte ratio complete blood count lab results biomarker guides https://libby.health/guides/nucleated-red-blood-cell-count https://libby.health/guides/nucleated-red-blood-cell-count Wed, 11 Nov 2026 00:00:00 GMT Nucleated red blood cells are young red cells that belong in the marrow. Why adults should have none, what a positive count means, and when it's urgent. nucleated red blood cells NRBC complete blood count lab results biomarker guides https://libby.health/guides/omega-3-omega-6-fatty-acid-panel https://libby.health/guides/omega-3-omega-6-fatty-acid-panel Wed, 11 Nov 2026 00:00:00 GMT A whole-blood omega-3 and omega-6 panel reports EPA, DPA, DHA, linoleic and arachidonic acid, two totals and two ratios. Here's what each one means. omega-3 omega-6 fatty acids lab results biomarker guides https://libby.health/guides/parathyroid-hormone https://libby.health/guides/parathyroid-hormone Wed, 11 Nov 2026 00:00:00 GMT Parathyroid hormone (PTH) sets your blood calcium. The normal range, what a high or low PTH usually means, why it's read with calcium, and when it's urgent. PTH parathyroid hormone hyperparathyroidism calcium lab results biomarker guides https://libby.health/guides/plasma-free-hemoglobin https://libby.health/guides/plasma-free-hemoglobin Wed, 11 Nov 2026 00:00:00 GMT Plasma free hemoglobin measures hemoglobin loose in your blood. What's normal, how a hard blood draw fakes a high result, and when it's urgent. plasma free hemoglobin hemolysis lab results biomarker guides https://libby.health/guides/potassium https://libby.health/guides/potassium Wed, 11 Nov 2026 00:00:00 GMT Potassium keeps your heart and muscles firing. Here's the normal range, the lowest-risk zone, the usual causes of low and high results, and when it's urgent. potassium electrolytes lab results biomarker guides https://libby.health/guides/procalcitonin https://libby.health/guides/procalcitonin Wed, 11 Nov 2026 00:00:00 GMT Procalcitonin rises fast in bacterial infection and sepsis. Here's the normal level, what each cutoff means, how to read it with CRP, and when it's urgent. procalcitonin PCT sepsis lab results biomarker guides https://libby.health/guides/progesterone https://libby.health/guides/progesterone Wed, 11 Nov 2026 00:00:00 GMT Progesterone shows whether you ovulated. See normal levels by cycle phase and pregnancy, what a low day-21 result means, and how to read it with LH and FSH. progesterone hormones fertility lab results biomarker guides https://libby.health/guides/prolactin https://libby.health/guides/prolactin Wed, 11 Nov 2026 00:00:00 GMT Prolactin is the milk-making hormone. Here's a normal level, the usual reasons it runs high, how to read it with TSH and kidney tests, and when it's urgent. prolactin pituitary hormones lab results biomarker guides https://libby.health/guides/prothrombin-time-inr https://libby.health/guides/prothrombin-time-inr Wed, 11 Nov 2026 00:00:00 GMT PT and INR measure how fast your blood clots. Here's a normal INR, the target on warfarin, the common reasons it runs high, and when a result is urgent. PT/INR prothrombin time warfarin lab results biomarker guides https://libby.health/guides/psa-total-free https://libby.health/guides/psa-total-free Wed, 11 Nov 2026 00:00:00 GMT PSA is a prostate protein. Here's what's normal for your age, what percent free PSA adds, the usual reasons PSA runs high, and when a result is urgent. PSA free PSA prostate lab results biomarker guides https://libby.health/guides/red-blood-cell-count https://libby.health/guides/red-blood-cell-count Wed, 11 Nov 2026 00:00:00 GMT Your RBC count is how many red cells are in your blood. Here is what is normal, what low or high usually means, and how to read it with MCV. red blood cell count RBC complete blood count anemia lab results biomarker guides https://libby.health/guides/renin https://libby.health/guides/renin Wed, 11 Nov 2026 00:00:00 GMT Renin is the kidney hormone that starts the blood-pressure chain. What's normal, how posture, salt and pills move it, and what high or low renin means. renin blood pressure hormones lab results biomarker guides https://libby.health/guides/reticulocyte-count https://libby.health/guides/reticulocyte-count Wed, 11 Nov 2026 00:00:00 GMT Reticulocytes are your newest red blood cells. Here's a normal count, what high and low results mean, how to read it with MCV and ferritin, and when to act. reticulocyte count red blood cells anemia lab results biomarker guides https://libby.health/guides/reticulocyte-hemoglobin-equivalent https://libby.health/guides/reticulocyte-hemoglobin-equivalent Wed, 11 Nov 2026 00:00:00 GMT Ret-He shows how much iron reached the red cells your marrow made in the past few days. Normal range, study cutoffs, and why it helps when ferritin misleads. Ret-He CHr reticulocyte hemoglobin iron deficiency lab results biomarker guides https://libby.health/guides/rheumatoid-factor https://libby.health/guides/rheumatoid-factor Wed, 11 Nov 2026 00:00:00 GMT Rheumatoid factor is an antibody tied to rheumatoid arthritis. What a normal result is, what a positive one usually means, and how to read it with anti-CCP. rheumatoid factor rheumatoid arthritis autoimmune lab results biomarker guides https://libby.health/guides/serum-osmolality https://libby.health/guides/serum-osmolality Wed, 11 Nov 2026 00:00:00 GMT Serum osmolality shows how concentrated your blood is. Here's the normal range, what makes it high or low, how to read it with sodium, and when it's urgent. serum osmolality osmolal gap lab results biomarker guides https://libby.health/guides/shbg https://libby.health/guides/shbg Wed, 11 Nov 2026 00:00:00 GMT SHBG holds testosterone and estrogen in your blood. Here's what's normal, what low or high SHBG usually means, and how to read it with free testosterone. SHBG testosterone hormones lab results biomarker guides https://libby.health/guides/sickle-cell-screen https://libby.health/guides/sickle-cell-screen Wed, 11 Nov 2026 00:00:00 GMT A sickle cell screen checks blood for hemoglobin S. What a positive or negative result means, when it can be wrong, and which test sorts trait from disease. sickle cell screen sickle cell trait hemoglobin S lab results biomarker guides https://libby.health/guides/small-ldl-particles https://libby.health/guides/small-ldl-particles Wed, 11 Nov 2026 00:00:00 GMT What LDL Small, LDL Medium, LDL Pattern, LDL Peak Size and HDL Large mean, how pattern B is set, and what particle size really adds to heart risk. small LDL LDL pattern lipoprotein particle size lab results biomarker guides https://libby.health/guides/sodium https://libby.health/guides/sodium Wed, 11 Nov 2026 00:00:00 GMT Blood sodium mostly tracks water. Here's the normal range, what optimizers aim for, the common causes of low and high sodium, and when it's urgent. sodium electrolytes lab results biomarker guides https://libby.health/guides/soluble-transferrin-receptor https://libby.health/guides/soluble-transferrin-receptor Wed, 11 Nov 2026 00:00:00 GMT sTfR rises when your red-cell factory runs short of iron or speeds up. Normal ranges by lab method, what high and low mean, and how to read it with ferritin. sTfR soluble transferrin receptor iron tests anemia biomarker guides https://libby.health/guides/thrombin-time https://libby.health/guides/thrombin-time Wed, 11 Nov 2026 00:00:00 GMT The thrombin time checks the last step of clotting. What's normal, why heparin or dabigatran lengthen it, and how labs spot a fibrinogen problem. thrombin time coagulation lab results biomarker guides https://libby.health/guides/thyroglobulin https://libby.health/guides/thyroglobulin Wed, 11 Nov 2026 00:00:00 GMT Thyroglobulin (Tg) comes from thyroid tissue. Here's the normal range with a thyroid, the targets after thyroid-cancer surgery, and why TgAb matters. thyroglobulin thyroid cancer thyroid lab results biomarker guides https://libby.health/guides/thyroglobulin-antibodies https://libby.health/guides/thyroglobulin-antibodies Wed, 11 Nov 2026 00:00:00 GMT Thyroglobulin antibodies (TgAb) signal thyroid autoimmunity. What a normal result is, what a positive one usually means, and how to read it with TSH. thyroglobulin antibodies TgAb thyroid tests lab results biomarker guides https://libby.health/guides/thyroid-peroxidase-antibodies https://libby.health/guides/thyroid-peroxidase-antibodies Wed, 11 Nov 2026 00:00:00 GMT TPO antibodies show your immune system has targeted your thyroid. What a positive result means, how to read it with TSH, and how fast it changes. TPO antibodies thyroid Hashimoto's lab results biomarker guides https://libby.health/guides/total-ige https://libby.health/guides/total-ige Wed, 11 Nov 2026 00:00:00 GMT Total IgE is the allergy antibody in your blood. Here's a normal level, the usual causes of a high one, the optimal range, and when a low one matters. IgE allergy testing immune system lab results biomarker guides https://libby.health/guides/total-non-hdl-cholesterol https://libby.health/guides/total-non-hdl-cholesterol Wed, 11 Nov 2026 00:00:00 GMT Total cholesterol counts it all; non-HDL counts the part that builds plaque. Normal and optimal levels, common causes of high results, and how to read them. total cholesterol non-HDL cholesterol lipid panel lab results biomarker guides https://libby.health/guides/total-protein https://libby.health/guides/total-protein Wed, 11 Nov 2026 00:00:00 GMT Total protein is albumin plus globulins. Here's the normal range, what a high or low result usually means, how to read it with albumin, and when it's urgent. total protein albumin globulin lab results biomarker guides https://libby.health/guides/total-t3 https://libby.health/guides/total-t3 Wed, 11 Nov 2026 00:00:00 GMT Total T3 counts all the T3 in your blood, bound and free. Here's the normal and optimal range, why pregnancy and estrogen raise it, and what high or low means. total T3 thyroid lab results biomarker guides https://libby.health/guides/total-t4 https://libby.health/guides/total-t4 Wed, 11 Nov 2026 00:00:00 GMT Total T4 counts all the thyroxine in your blood, bound and free. Here's the normal range, why pregnancy and estrogen raise it, and when to check free T4. total T4 thyroid tests lab results biomarker guides https://libby.health/guides/transferrin https://libby.health/guides/transferrin Wed, 11 Nov 2026 00:00:00 GMT Transferrin is the protein that carries iron in your blood. Here's the normal range, why it runs high or low, and how to read it with ferritin and iron. transferrin iron tests lab results biomarker guides https://libby.health/guides/transferrin-saturation https://libby.health/guides/transferrin-saturation Wed, 11 Nov 2026 00:00:00 GMT Transferrin saturation is the share of your iron carriers holding iron. Here's what's normal, optimal, what low and high mean, and when to recheck it. transferrin saturation TSAT iron lab results biomarker guides https://libby.health/guides/uric-acid https://libby.health/guides/uric-acid Wed, 11 Nov 2026 00:00:00 GMT Uric acid is your body's purine waste. What a normal level is, the targets optimizers aim for, why it runs high, and how it links to gout. uric acid urate gout lab results biomarker guides https://libby.health/guides/urine-albumin-creatinine-ratio https://libby.health/guides/urine-albumin-creatinine-ratio Wed, 11 Nov 2026 00:00:00 GMT UACR shows albumin leaking from your kidneys into urine. What's normal, what optimal looks like, the common causes of a high result, and when to act. UACR albuminuria kidney health lab results biomarker guides https://libby.health/guides/urine-bacteria https://libby.health/guides/urine-bacteria Wed, 11 Nov 2026 00:00:00 GMT Bacteria on a urinalysis often mean a contaminated sample or harmless bacteriuria. Here's how it's graded, how it relates to a culture, and when it matters. bacteria in urine bacteriuria urinalysis lab results biomarker guides https://libby.health/guides/urine-bilirubin https://libby.health/guides/urine-bilirubin Wed, 11 Nov 2026 00:00:00 GMT Bilirubin in urine points to the liver or bile ducts. What normal is, the common causes of a positive, how to read it with other tests, and when it's urgent. urine bilirubin urinalysis bilirubin liver health lab results biomarker guides https://libby.health/guides/urine-blood-hemoglobin https://libby.health/guides/urine-blood-hemoglobin Wed, 11 Nov 2026 00:00:00 GMT A positive urine blood test can mean red cells, free hemoglobin or muscle pigment. What's normal, common causes, the neighbors to check, and when it's urgent. urine blood hematuria urinalysis lab results biomarker guides https://libby.health/guides/urine-calcium https://libby.health/guides/urine-calcium Wed, 11 Nov 2026 00:00:00 GMT A 24-hour urine calcium shows how much calcium your kidneys pass. The normal range, why it runs high, the kidney-stone link, and what a low result means. urine calcium 24-hour urine kidney stones hypercalciuria lab results biomarker guides https://libby.health/guides/urine-casts https://libby.health/guides/urine-casts Wed, 11 Nov 2026 00:00:00 GMT Urine casts are protein plugs molded in the kidney's tubules. A few hyaline casts are usually harmless. Here's what the other types point to. urine casts hyaline casts urinalysis lab results biomarker guides https://libby.health/guides/urine-chloride https://libby.health/guides/urine-chloride Wed, 11 Nov 2026 00:00:00 GMT Urine chloride shows how much chloride your kidneys let go. The normal range, what under 20 mmol/L means in metabolic alkalosis, and the urine anion gap. urine chloride electrolytes urine tests lab results biomarker guides https://libby.health/guides/urine-color-and-appearance https://libby.health/guides/urine-color-and-appearance Wed, 11 Nov 2026 00:00:00 GMT What yellow, amber, red, brown or cloudy urine means on a urinalysis, why hydration drives most color change, and which colors need prompt care. urine color urine appearance urinalysis hydration lab results biomarker guides https://libby.health/guides/urine-creatinine https://libby.health/guides/urine-creatinine Wed, 11 Nov 2026 00:00:00 GMT Urine creatinine shows how dilute a sample is, whether a 24-hour collection is complete, and anchors urine ratios. What's normal and why it runs low or high. urine creatinine creatinine 24-hour urine urinalysis kidney lab results biomarker guides https://libby.health/guides/urine-crystals https://libby.health/guides/urine-crystals Wed, 11 Nov 2026 00:00:00 GMT Most urine crystals are harmless and form after the sample cools. What calcium oxalate and amorphous crystals mean, which types matter, and when to act. urine crystals calcium oxalate amorphous sediment urinalysis lab results biomarker guides https://libby.health/guides/urine-epithelial-cells https://libby.health/guides/urine-epithelial-cells Wed, 11 Nov 2026 00:00:00 GMT Squamous cells in urine usually mean skin cells got into the sample. Here's what's normal, when renal tubular cells matter, and when to get care. epithelial cells squamous epithelial cells urinalysis lab results biomarker guides https://libby.health/guides/urine-glucose https://libby.health/guides/urine-glucose Wed, 11 Nov 2026 00:00:00 GMT Glucose in urine usually means blood sugar passed your kidneys' limit. What a normal result is, the common causes of a positive, and when it's urgent. urine glucose urinalysis blood sugar lab results biomarker guides https://libby.health/guides/urine-ketones https://libby.health/guides/urine-ketones Wed, 11 Nov 2026 00:00:00 GMT Urine ketones show your body burning fat. Here's what negative, trace, small and large mean, why strips miss mild ketosis, and when ketones are urgent. urine ketones urinalysis ketosis lab results biomarker guides https://libby.health/guides/urine-leukocyte-esterase https://libby.health/guides/urine-leukocyte-esterase Wed, 11 Nov 2026 00:00:00 GMT Leukocyte esterase flags white blood cells in your urine. Here's what a positive means, the usual causes, how to read it with nitrite, and when to get care. leukocyte esterase urinalysis urinary tract infection lab results biomarker guides https://libby.health/guides/urine-nitrite https://libby.health/guides/urine-nitrite Wed, 11 Nov 2026 00:00:00 GMT Nitrite on a urinalysis points to bacteria in the bladder. What a positive result means, why a negative one can miss an infection, and when it's urgent. urine nitrite urinalysis urinary tract infection lab results biomarker guides https://libby.health/guides/urine-ph https://libby.health/guides/urine-ph Wed, 11 Nov 2026 00:00:00 GMT Urine pH shows how much acid your kidneys are clearing. What's normal, the optimal band, why urine runs acidic or alkaline, and when it matters. urine pH urinalysis kidney stones lab results biomarker guides https://libby.health/guides/urine-potassium https://libby.health/guides/urine-potassium Wed, 11 Nov 2026 00:00:00 GMT Urine potassium shows how much potassium your kidneys let go. Normal 24-hour ranges, spot ratios, and what low or high means when blood potassium is off. urine potassium potassium kidney tests lab results biomarker guides https://libby.health/guides/urine-protein https://libby.health/guides/urine-protein Wed, 11 Nov 2026 00:00:00 GMT Protein on a urinalysis is graded negative to 4+. What each grade means, the common temporary causes, when it points to kidney disease, and when it's urgent. urine protein proteinuria urinalysis kidney lab results biomarker guides https://libby.health/guides/urine-protein-creatinine-ratio https://libby.health/guides/urine-protein-creatinine-ratio Wed, 11 Nov 2026 00:00:00 GMT UPCR measures all the protein leaking into your urine. What's normal, what 150, 500 and 3,500 mg/g mean, the common causes, and when a high result is urgent. UPCR proteinuria urine protein kidney health lab results biomarker guides https://libby.health/guides/urine-red-blood-cells https://libby.health/guides/urine-red-blood-cells Wed, 11 Nov 2026 00:00:00 GMT Urine red cells are counted per high-power field under a microscope. What's normal, what misshapen cells and casts mean, and the AUA/SUFU workup. urine red blood cells microscopic hematuria urinalysis lab results biomarker guides https://libby.health/guides/urine-sodium https://libby.health/guides/urine-sodium Wed, 11 Nov 2026 00:00:00 GMT Urine sodium shows how much salt your kidneys let go. Here's the 24-hour range, spot vs 24-hour tests, FENa, salt targets, and what low or high means. urine sodium FENa salt intake lab results biomarker guides https://libby.health/guides/urine-specific-gravity https://libby.health/guides/urine-specific-gravity Wed, 11 Nov 2026 00:00:00 GMT Urine specific gravity shows how concentrated your urine is. Here's the normal range, what high and low results usually mean, and when to get care. urine specific gravity urinalysis hydration lab results biomarker guides https://libby.health/guides/urine-urobilinogen https://libby.health/guides/urine-urobilinogen Wed, 11 Nov 2026 00:00:00 GMT Urine urobilinogen tracks bilirubin's trip from liver to gut and back. Here's the normal 0.2–1.0 range, what high or low means, and when it's urgent. urobilinogen urinalysis bilirubin liver tests biomarker guides https://libby.health/guides/urine-white-blood-cells https://libby.health/guides/urine-white-blood-cells Wed, 11 Nov 2026 00:00:00 GMT White blood cells in urine usually signal infection or inflammation. Here's the normal count, the common causes, what to read beside it, and when it's urgent. urine white blood cells urinalysis pyuria lab results biomarker guides https://libby.health/guides/urine-yeast https://libby.health/guides/urine-yeast Wed, 11 Nov 2026 00:00:00 GMT Yeast on a urinalysis can be vaginal yeast in the sample or harmless colonization. Here's who gets true candiduria, how it's confirmed and when it's treated. yeast in urine candiduria Candida urinalysis lab results biomarker guides https://libby.health/guides/von-willebrand-factor-activity https://libby.health/guides/von-willebrand-factor-activity Wed, 11 Nov 2026 00:00:00 GMT VWF activity shows how well von Willebrand factor grips platelets: the normal range, the activity-to-antigen ratio, the four test types and what low means. von Willebrand factor VWF activity bleeding disorders lab results biomarker guides https://libby.health/guides/von-willebrand-factor-antigen https://libby.health/guides/von-willebrand-factor-antigen Wed, 11 Nov 2026 00:00:00 GMT VWF antigen shows how much von Willebrand factor is in your blood: the normal range, the 2021 von Willebrand disease cutoffs, and why levels swing. von Willebrand factor VWF antigen bleeding disorders clotting tests lab results biomarker guides https://libby.health/guides/platelet-count https://libby.health/guides/platelet-count Tue, 10 Nov 2026 00:00:00 GMT Platelets help your blood clot. Here's a normal count, why it runs low or high, how to read it with your CBC and ferritin, and when it's urgent. Platelet count CBC lab results biomarker guides https://libby.health/guides/phosphorus https://libby.health/guides/phosphorus Mon, 09 Nov 2026 00:00:00 GMT Phosphorus is a mineral shared by your bones, cells and kidneys. Here's the normal range, what low and high results usually mean, and when it's urgent. phosphorus phosphate kidney health lab results biomarker guides https://libby.health/guides/mpv https://libby.health/guides/mpv Sun, 08 Nov 2026 00:00:00 GMT MPV is the average size of your platelets. What a normal MPV is, what high and low results mean, how to read it with your platelet count, and when to act. MPV platelets complete blood count biomarker guides https://libby.health/guides/methylmalonic-acid https://libby.health/guides/methylmalonic-acid Sat, 07 Nov 2026 00:00:00 GMT Methylmalonic acid (MMA) shows whether vitamin B12 is working inside your cells. Normal levels, common causes of a high result, and how to read it with B12. methylmalonic acid vitamin B12 lab results biomarker guides https://libby.health/guides/mcv https://libby.health/guides/mcv Fri, 06 Nov 2026 00:00:00 GMT MCV is the average size of your red blood cells. Here's what's normal, what a low or high MCV usually means, and how to read it with RDW and B12. MCV complete blood count anemia lab results biomarker guides https://libby.health/guides/health-records-in-one-place https://libby.health/guides/health-records-in-one-place Thu, 05 Nov 2026 00:00:00 GMT Your health data is scattered. Your body is not. What becomes possible when every lab result and record sits in one place that belongs to you. own your data personal health record lab results https://libby.health/guides/hipaa-to-tefca https://libby.health/guides/hipaa-to-tefca Thu, 05 Nov 2026 00:00:00 GMT The legal right to your records is broad, and since late 2023 a national network can deliver them. How the law got there, and how you can get your records today. own your data medical records TEFCA https://libby.health/guides/mchc https://libby.health/guides/mchc Thu, 05 Nov 2026 00:00:00 GMT MCHC shows how tightly hemoglobin is packed in your red cells. Normal range, why it runs low or high, how to read it with MCV and RDW, and lab errors. MCHC red blood cell indices complete blood count lab results biomarker guides https://libby.health/guides/start-here https://libby.health/guides/start-here Thu, 05 Nov 2026 00:00:00 GMT New to Libby? What it does today, what's coming, and the guides worth reading first: owning your records and reading your results. getting started own your data https://libby.health/guides/vision https://libby.health/guides/vision Thu, 05 Nov 2026 00:00:00 GMT Libby starts as the record, because everything we want to build needs something real to reason from. Then an agent that acts for you, then better medicine. own your data personal health record https://libby.health/guides/mch https://libby.health/guides/mch Wed, 04 Nov 2026 00:00:00 GMT MCH is the average amount of hemoglobin in each red blood cell. Here's the normal range, why it runs low or high, and how to read it with MCV and ferritin. MCH red blood cells complete blood count lab results biomarker guides https://libby.health/guides/magnesium https://libby.health/guides/magnesium Tue, 03 Nov 2026 00:00:00 GMT Magnesium keeps your nerves, muscles and heart working. Here's the normal range, why it runs low, how to read it with potassium and calcium, and when it's urgent. magnesium electrolytes lab results biomarker guides https://libby.health/guides/luteinizing-hormone-lh https://libby.health/guides/luteinizing-hormone-lh Mon, 02 Nov 2026 00:00:00 GMT LH is your brain's signal to the ovaries and testes. See normal LH by sex and cycle phase, what high or low LH usually means, and how to read it. LH hormones fertility menopause testosterone lab results biomarker guides https://libby.health/guides/lipase https://libby.health/guides/lipase Sun, 01 Nov 2026 00:00:00 GMT Lipase is the pancreas's fat-digesting enzyme. Here's what a normal level is, what high and low results usually mean, and when a high lipase is urgent. lipase pancreas pancreatitis lab results biomarker guides https://libby.health/guides/lactate-dehydrogenase https://libby.health/guides/lactate-dehydrogenase Sat, 31 Oct 2026 00:00:00 GMT LDH is an energy enzyme in almost every cell. Here's what a normal level is, why it runs high, how its neighbors find the source, and when it's urgent. LDH lactate dehydrogenase hemolysis lab results biomarker guides https://libby.health/guides/lactate https://libby.health/guides/lactate Fri, 30 Oct 2026 00:00:00 GMT Lactate is a fuel your cells make and burn all day. Here's the normal range, what raises it, how to read it with pH and bicarbonate, and when it's urgent. lactate lactic acid lab results biomarker guides https://libby.health/guides/iron-panel https://libby.health/guides/iron-panel Thu, 29 Oct 2026 00:00:00 GMT An iron panel shows the iron in your blood, the room to carry more and how full the carriers are. Here's what's normal, optimal, and what patterns mean. iron panel iron transferrin saturation lab results biomarker guides https://libby.health/guides/ionized-calcium https://libby.health/guides/ionized-calcium Wed, 28 Oct 2026 00:00:00 GMT Ionized calcium is the free, active calcium in your blood. Here's the normal range, what low and high levels usually mean, and how to read it with PTH. ionized calcium calcium parathyroid lab results biomarker guides https://libby.health/guides/immature-granulocyte-count https://libby.health/guides/immature-granulocyte-count Tue, 27 Oct 2026 00:00:00 GMT Immature granulocytes are young white cells released early. Here's a normal level, why IG runs high, how to read it with your CBC, and when it's urgent. immature granulocytes complete blood count white blood cells lab results biomarker guides https://libby.health/guides/igf-1 https://libby.health/guides/igf-1 Mon, 26 Oct 2026 00:00:00 GMT IGF-1 tracks growth hormone. Here's the normal range for your age, what optimizers aim for, why it runs low or high, and when to see a specialist. IGF-1 growth hormone hormones lab results biomarker guides https://libby.health/guides/globulin-ag-ratio https://libby.health/guides/globulin-ag-ratio Sun, 25 Oct 2026 00:00:00 GMT Globulin is the non-albumin protein in your blood. Here's a normal globulin and A/G ratio, why they run high or low, and when a result needs follow-up. globulin A/G ratio total protein lab results biomarker guides https://libby.health/guides/ggt https://libby.health/guides/ggt Sat, 24 Oct 2026 00:00:00 GMT GGT is a liver and bile-duct enzyme. What a normal level is, why it runs high, how to read it with ALP, and when a high result is urgent. GGT liver enzymes lab results biomarker guides https://libby.health/guides/fsh https://libby.health/guides/fsh Fri, 23 Oct 2026 00:00:00 GMT FSH is your brain's signal to the ovaries or testes. See normal levels by sex and cycle phase, what high or low FSH usually means, and how to read it. FSH hormones fertility menopause lab results biomarker guides https://libby.health/guides/folate https://libby.health/guides/folate Thu, 22 Oct 2026 00:00:00 GMT Folate is the B vitamin cells use to build DNA. Here's what a normal level is, why it runs low or high, how to read it with B12, and when to act. folate folic acid vitamin B9 lab results biomarker guides https://libby.health/guides/fasting-insulin https://libby.health/guides/fasting-insulin Wed, 21 Oct 2026 00:00:00 GMT Fasting insulin shows how hard your pancreas works to keep blood sugar normal. Here's the normal and optimal range, what high means, and when to worry. fasting insulin insulin resistance lab results biomarker guides https://libby.health/guides/erythrocyte-sedimentation-rate https://libby.health/guides/erythrocyte-sedimentation-rate Tue, 20 Oct 2026 00:00:00 GMT ESR (sed rate) tracks inflammation. Here's a normal ESR by age and sex, the common reasons it runs high, how to read it with CRP, and when it's urgent. ESR inflammation lab results biomarker guides https://libby.health/guides/d-dimer https://libby.health/guides/d-dimer Mon, 19 Oct 2026 00:00:00 GMT D-dimer shows your body is breaking down a blood clot. Here's the normal cutoff, the common reasons it runs high, and when a result is urgent. D-dimer blood clots lab results biomarker guides https://libby.health/guides/cystatin-c https://libby.health/guides/cystatin-c Sun, 18 Oct 2026 00:00:00 GMT Cystatin C is a kidney filtration marker that muscle barely moves. What's normal, what a high result means, how it pairs with creatinine, and when it's urgent. cystatin C eGFR kidney health lab results biomarker guides https://libby.health/guides/creatine-kinase https://libby.health/guides/creatine-kinase Sat, 17 Oct 2026 00:00:00 GMT CK is a muscle enzyme. Here's what a normal level is, why a hard workout can push it into the thousands, how to read it with AST and ALT, and when it's urgent. CK creatine kinase muscle enzymes lab results biomarker guides https://libby.health/guides/cortisol https://libby.health/guides/cortisol Fri, 16 Oct 2026 00:00:00 GMT Cortisol runs on a daily clock. Here's a normal morning level, what high and low results usually mean, how to read it with ACTH, and when low is urgent. cortisol adrenal glands hormones lab results biomarker guides https://libby.health/guides/copper https://libby.health/guides/copper Thu, 15 Oct 2026 00:00:00 GMT Most copper in your blood rides on one protein. Here's the normal range, the optimal ladder, why copper runs high or low, and how to read it with zinc. copper trace minerals lab results biomarker guides https://libby.health/guides/chloride https://libby.health/guides/chloride Wed, 14 Oct 2026 00:00:00 GMT Chloride is sodium's salt partner. Here's the normal range, what low or high chloride usually means, how to read it with sodium and CO2, and when to act. chloride electrolytes lab results biomarker guides https://libby.health/guides/ceruloplasmin https://libby.health/guides/ceruloplasmin Tue, 13 Oct 2026 00:00:00 GMT Ceruloplasmin carries most of your blood's copper. What a normal level is, what low and high results usually mean, and when to think of Wilson disease. ceruloplasmin copper Wilson disease lab results biomarker guides https://libby.health/guides/cardiac-troponin https://libby.health/guides/cardiac-troponin Mon, 12 Oct 2026 00:00:00 GMT Troponin is the blood test for heart-muscle injury. Here's what's normal on each test, what a high result usually means, and when it's an emergency. troponin heart health lab results biomarker guides https://libby.health/guides/calcium https://libby.health/guides/calcium Sun, 11 Oct 2026 00:00:00 GMT Blood calcium is tightly controlled. Here's the normal range, the usual reasons it runs high or low, how to read it with PTH and albumin, and when it's urgent. calcium electrolytes lab results biomarker guides https://libby.health/guides/c-peptide https://libby.health/guides/c-peptide Sat, 10 Oct 2026 00:00:00 GMT C-peptide shows how much insulin your pancreas makes. Here's the normal range, what high and low results usually mean, and how to read it with blood sugar. C-peptide insulin blood sugar lab results biomarker guides https://libby.health/guides/bun https://libby.health/guides/bun Fri, 09 Oct 2026 00:00:00 GMT BUN measures urea, the waste your liver makes from protein. Here's a normal level, why it runs high or low, and how to read it next to creatinine. BUN kidney function lab results biomarker guides https://libby.health/guides/bnp-nt-probnp https://libby.health/guides/bnp-nt-probnp Thu, 08 Oct 2026 00:00:00 GMT BNP and NT-proBNP rise when the heart is strained. What's normal by age, what else raises them, how to read them with other tests, and when it's urgent. BNP NT-proBNP heart failure lab results biomarker guides https://libby.health/guides/bilirubin https://libby.health/guides/bilirubin Wed, 07 Oct 2026 00:00:00 GMT Bilirubin comes from old red blood cells. Normal levels, why it runs high (often Gilbert syndrome), how to read it next to ALT and ALP, and when it's urgent. bilirubin liver tests lab results biomarker guides https://libby.health/guides/bicarbonate-total-co2 https://libby.health/guides/bicarbonate-total-co2 Tue, 06 Oct 2026 00:00:00 GMT The CO2 on your metabolic panel is bicarbonate. Here's the normal range, what low or high usually means, how to read it with chloride, and when it's urgent. CO2 bicarbonate electrolytes lab results biomarker guides https://libby.health/guides/anti-mullerian-hormone-amh https://libby.health/guides/anti-mullerian-hormone-amh Mon, 05 Oct 2026 00:00:00 GMT AMH tracks how many eggs your ovaries have left. See normal levels by age, what low and high results usually mean, and what AMH predicts. AMH fertility ovarian reserve lab results biomarker guides https://libby.health/guides/anion-gap https://libby.health/guides/anion-gap Sun, 04 Oct 2026 00:00:00 GMT The anion gap is a quick math check on your electrolytes. What's normal, why it runs high or low, how to read it with bicarbonate and albumin, and when to act. anion gap electrolytes acid-base lab results biomarker guides https://libby.health/guides/amylase https://libby.health/guides/amylase Sat, 03 Oct 2026 00:00:00 GMT Amylase is a starch-digesting enzyme from your pancreas and salivary glands. What's normal, why it runs high or low, and when a high result is urgent. amylase pancreas lab results biomarker guides https://libby.health/guides/activated-partial-thromboplastin-time https://libby.health/guides/activated-partial-thromboplastin-time Fri, 02 Oct 2026 00:00:00 GMT aPTT times how fast your plasma clots. Here's the normal range, what a long or short result usually means, how to read it with PT, and when it's urgent. aPTT PTT clotting tests lab results biomarker guides https://libby.health/guides/absolute-neutrophil-count https://libby.health/guides/absolute-neutrophil-count Thu, 01 Oct 2026 00:00:00 GMT ANC counts the infection-fighting neutrophils in your blood. The normal range, why it runs low or high, how to read it with your CBC, and when to act. absolute neutrophil count neutrophils complete blood count lab results biomarker guides https://libby.health/guides/absolute-monocyte-count https://libby.health/guides/absolute-monocyte-count Wed, 30 Sep 2026 00:00:00 GMT Monocytes are white blood cells that clean up and call in help. Here's a normal count, why it runs high or low, and when a result needs a closer look. absolute monocyte count monocytes complete blood count biomarker guides https://libby.health/guides/absolute-lymphocyte-count https://libby.health/guides/absolute-lymphocyte-count Tue, 29 Sep 2026 00:00:00 GMT Lymphocytes are your B, T and NK immune cells. Here's a normal absolute count, what a low or high result usually means, and when it needs a closer look. absolute lymphocyte count lymphocytes CBC lab results biomarker guides https://libby.health/guides/absolute-eosinophil-count https://libby.health/guides/absolute-eosinophil-count Mon, 28 Sep 2026 00:00:00 GMT Eosinophils are white cells tied to allergy and parasites. Here's a normal count, the usual causes of a high one, the optimal range, and when it's urgent. eosinophils complete blood count white blood cells lab results biomarker guides https://libby.health/guides/absolute-basophil-count https://libby.health/guides/absolute-basophil-count Sun, 27 Sep 2026 00:00:00 GMT Basophils are the rarest white blood cell. Here's a normal basophil count, what a high or low result usually means, and when a high count needs a closer look. basophils complete blood count white blood cells lab results biomarker guides https://libby.health/guides/white-blood-cell-count https://libby.health/guides/white-blood-cell-count Sat, 26 Sep 2026 00:00:00 GMT Your WBC counts the immune cells in your blood. Here's the normal and optimal range, why it runs high or low, how to read the differential, and when to act. white blood cells complete blood count lab results biomarker guides https://libby.health/guides/hemoglobin-hematocrit https://libby.health/guides/hemoglobin-hematocrit Fri, 25 Sep 2026 00:00:00 GMT Hemoglobin carries oxygen; hematocrit is the share of your blood that's red cells. Here's what's normal, what low or high usually means, and what's urgent. hemoglobin hematocrit complete blood count anemia lab results biomarker guides https://libby.health/guides/albumin https://libby.health/guides/albumin Thu, 24 Sep 2026 00:00:00 GMT Albumin is the main protein in your blood. Here's the normal range, what optimizers aim for, why it usually runs low, and how to read it with its neighbors. albumin liver kidney lab results biomarker guides https://libby.health/guides/alp https://libby.health/guides/alp Thu, 24 Sep 2026 00:00:00 GMT ALP is an enzyme from your liver and bones. Here's a normal level, why it runs high or low, how GGT tells liver from bone, and when it's urgent. ALP alkaline phosphatase liver enzymes bone health lab results biomarker guides https://libby.health/guides/alt https://libby.health/guides/alt Thu, 24 Sep 2026 00:00:00 GMT ALT is a liver enzyme. Here's what a normal level is, the most common reasons it runs high, how to read it with AST and ALP, and when a high result is urgent. ALT liver enzymes lab results biomarker guides https://libby.health/guides/apob https://libby.health/guides/apob Thu, 24 Sep 2026 00:00:00 GMT ApoB counts the particles that clog arteries. Here's a normal level, the optimal targets, why it can be high when LDL looks fine, and what moves it. ApoB cholesterol heart health lab results biomarker guides https://libby.health/guides/ast https://libby.health/guides/ast Thu, 24 Sep 2026 00:00:00 GMT AST is an enzyme in liver, muscle and red blood cells. What a normal level is, why it runs high, how to read it with ALT and CK, and when it's urgent. AST liver enzymes lab results biomarker guides https://libby.health/guides/dhea-s https://libby.health/guides/dhea-s Thu, 24 Sep 2026 00:00:00 GMT DHEA-S is an adrenal hormone that falls with age. Here's the normal range by age and sex, what high and low levels usually mean, and when it's urgent. DHEA-S adrenal hormones lab results biomarker guides https://libby.health/guides/egfr-creatinine https://libby.health/guides/egfr-creatinine Thu, 24 Sep 2026 00:00:00 GMT eGFR shows how well your kidneys filter, and it's calculated from creatinine. What's normal, what a low eGFR usually means, and when it's urgent. eGFR creatinine kidney health lab results biomarker guides https://libby.health/guides/estradiol https://libby.health/guides/estradiol Thu, 24 Sep 2026 00:00:00 GMT Estradiol (E2) is your main estrogen. See normal levels for men and women, what high or low results usually mean, and how to read E2 with FSH and LH. estradiol hormones lab results biomarker guides https://libby.health/guides/fasting-glucose https://libby.health/guides/fasting-glucose Thu, 24 Sep 2026 00:00:00 GMT Fasting glucose shows how your body holds blood sugar overnight. Here's what's normal, what's optimal, why it runs high or low, and when a result is urgent. fasting glucose blood sugar prediabetes lab results biomarker guides https://libby.health/guides/ferritin https://libby.health/guides/ferritin Thu, 24 Sep 2026 00:00:00 GMT Ferritin shows how full your iron stores are. Here's what's normal and optimal, why it runs low or high, how to read it with iron saturation, and when to act. ferritin iron lab results biomarker guides https://libby.health/guides/free-t3 https://libby.health/guides/free-t3 Thu, 24 Sep 2026 00:00:00 GMT Free T3 is the active thyroid hormone. Here's the normal and optimal range, what high or low usually means, and how to read it with TSH and free T4. free T3 thyroid lab results biomarker guides https://libby.health/guides/free-t4 https://libby.health/guides/free-t4 Thu, 24 Sep 2026 00:00:00 GMT Free T4 is the unbound thyroid hormone in your blood. Here's what a normal level is, what optimizers aim for, why it runs low or high, and when it's urgent. free T4 thyroid tests lab results biomarker guides https://libby.health/guides/hba1c https://libby.health/guides/hba1c Thu, 24 Sep 2026 00:00:00 GMT A1C shows your average blood sugar over about 3 months. Here's what's normal, what optimal looks like, why it runs high or low, and when to get care. HbA1c A1C blood sugar lab results biomarker guides https://libby.health/guides/hdl-cholesterol https://libby.health/guides/hdl-cholesterol Thu, 24 Sep 2026 00:00:00 GMT HDL is the "good" cholesterol. Here's what a normal level is, why it runs low, when a high HDL stops helping, and how to read it with triglycerides. HDL cholesterol cholesterol lab results biomarker guides https://libby.health/guides/homocysteine https://libby.health/guides/homocysteine Thu, 24 Sep 2026 00:00:00 GMT Homocysteine is an amino acid that B vitamins and your kidneys clear. What is normal, what optimizers aim for, why it runs high, and how to read it with B12. homocysteine B vitamins lab results biomarker guides https://libby.health/guides/hs-crp https://libby.health/guides/hs-crp Thu, 24 Sep 2026 00:00:00 GMT CRP is your body's inflammation signal. Here's what a normal CRP and hs-CRP is, the common reasons it runs high, and when a high result needs care. CRP hs-CRP inflammation lab results biomarker guides https://libby.health/guides/ldl-cholesterol https://libby.health/guides/ldl-cholesterol Thu, 24 Sep 2026 00:00:00 GMT LDL carries cholesterol into artery walls. Here's what a normal and optimal LDL is, why it runs high, how to read it with ApoB and Lp(a), and when to act. LDL cholesterol lipid panel lab results biomarker guides https://libby.health/guides/lp-a https://libby.health/guides/lp-a Thu, 24 Sep 2026 00:00:00 GMT Lp(a) is an inherited cholesterol particle. Here's a normal level, the optimal targets, what a high result means for heart risk, and how to read the units. Lp(a) lipoprotein(a) cholesterol heart health lab results biomarker guides https://libby.health/guides/omega-3-index https://libby.health/guides/omega-3-index Thu, 24 Sep 2026 00:00:00 GMT The omega-3 index is the share of EPA and DHA in your red blood cells. Here's what's typical, why 8% is the usual target, and what raises it. omega-3 index fatty acids lab results biomarker guides https://libby.health/guides/rdw https://libby.health/guides/rdw Thu, 24 Sep 2026 00:00:00 GMT RDW measures how much your red blood cells vary in size. Here's what's normal, what a high RDW usually means, and how to read it with MCV and ferritin. RDW complete blood count anemia lab results biomarker guides https://libby.health/guides/testosterone https://libby.health/guides/testosterone Thu, 24 Sep 2026 00:00:00 GMT What a normal testosterone level is for men and women, the optimal ranges people aim for, the most common causes of low T, and when a result is urgent. testosterone hormones lab results biomarker guides https://libby.health/guides/triglycerides https://libby.health/guides/triglycerides Thu, 24 Sep 2026 00:00:00 GMT Triglycerides are the fat in your blood. Here's what a normal level is, why they run high, how to read them with HDL and LDL, and when a result is urgent. triglycerides lipid panel lab results biomarker guides https://libby.health/guides/tsh https://libby.health/guides/tsh Thu, 24 Sep 2026 00:00:00 GMT TSH is your pituitary's signal to your thyroid. Here's what a normal TSH is, what optimizers aim for, why it runs high or low, and when it's urgent. TSH thyroid tests lab results biomarker guides https://libby.health/guides/vitamin-b12 https://libby.health/guides/vitamin-b12 Thu, 24 Sep 2026 00:00:00 GMT Vitamin B12 keeps your nerves and red blood cells healthy. Here's a normal level, why it runs low, how MMA settles a borderline result, and when to act fast. vitamin B12 methylmalonic acid lab results biomarker guides https://libby.health/guides/vitamin-d https://libby.health/guides/vitamin-d Thu, 24 Sep 2026 00:00:00 GMT Your vitamin D test measures 25-hydroxyvitamin D. What is normal, what optimizers aim for, why it runs low or high, and when a result is urgent. vitamin D 25-hydroxyvitamin D lab results biomarker guides