Not medical advice. I am a software engineer, not a physician. This page documents my own protocol and the research I read while building it. Talk to a qualified clinician before changing your supplementation, diet or any treatment. Lab reference ranges quoted here vary by laboratory and by individual.
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Blood is a liquid connective tissue comprising approximately 5 liters in an adult. It consists of plasma (55%), red blood cells (44%), and white blood cells plus platelets (1%). Blood is the body's universal transport medium — delivering oxygen, nutrients, hormones, and immune cells to every tissue while simultaneously removing waste products. The complete blood count (CBC) is the single most informative routine lab test, revealing anemia, infection, clotting disorders, and even early indicators of blood cancers. Maintaining healthy blood through proper nutrition (iron, B12, folate) directly impacts energy, immunity, and cognitive function.
Blood tests are the foundation of preventive medicine. The CBC alone can detect dozens of conditions, and adding iron studies and B vitamin markers provides a comprehensive picture of blood health.
| Test | What It Detects | Link |
|---|---|---|
| CBC (Complete Blood Count) | Red cells, white cells, platelets, hemoglobin, hematocrit, MCV. Detects anemia, infection, clotting disorders, and blood cancers | Lab Tests |
| Iron Panel (Serum Iron, TIBC) | Iron availability for hemoglobin synthesis; low serum iron with high TIBC indicates iron deficiency | Lab Tests |
| Ferritin | Iron storage marker; low ferritin (<30 ng/mL) indicates depleted iron stores even before anemia develops. Elevated ferritin may indicate inflammation or iron overload | Lab Tests |
| ESR (Erythrocyte Sedimentation Rate) | Non-specific inflammation marker; elevated ESR indicates chronic inflammation, infection, or autoimmune activity | Lab Tests |
| Vitamin B12 | Essential for red blood cell maturation and DNA synthesis; deficiency causes megaloblastic anemia and neurological damage | Lab Tests |
| Folate (B9) | Required for DNA synthesis and red blood cell production; deficiency causes macrocytic anemia and neural tube defects | Lab Tests |
Blood health depends on adequate iron (for hemoglobin), B vitamins (for red blood cell maturation), and omega-3 fatty acids (for reducing inflammation and improving blood fluidity).
| Supplement | How It Helps | Link |
|---|---|---|
| Iron (via Vitamin C for absorption) | Iron is the central atom in hemoglobin. Taking iron with vitamin C (ascorbic acid) increases absorption 2-3x by converting ferric iron to the absorbable ferrous form. Only supplement if ferritin is low. | Vitamin C |
| B-Complex (Methylated) | B12 and folate are essential for DNA synthesis during red blood cell production. Methylated forms ensure bioavailability regardless of MTHFR gene variants. | B-Complex |
| Omega-3 (EPA/DHA) | Reduces blood viscosity, lowers inflammatory markers (ESR, CRP), and improves red blood cell membrane flexibility for better microcirculation. | Omega-3 |
Do not supplement iron blindly: Iron is one of the few supplements that can be harmful in excess. Excess iron generates free radicals via the Fenton reaction and increases oxidative damage. Always check ferritin before supplementing. Target ferritin: 30-100 ng/mL for most adults.
Ferritin thresholds revised upward — the WHO cutoff of 15 ng/mL is too low. A 2025 study in Blood (ASH) using physiologically-based analysis established that serum ferritin thresholds for iron deficiency should be 33 μg/L for men and postmenopausal women, and 25 μg/L for premenopausal women — substantially higher than the WHO's traditional 15 ng/mL cutoff. This means many individuals previously classified as "normal" were in fact iron-deficient, explaining persistent symptoms of fatigue, poor exercise tolerance, and cognitive impairment. Non-anemic iron deficiency is at least twice as common as iron deficiency anemia, affecting over 2 billion people globally.
Reticulocyte hemoglobin (Ret-He) outperforms ferritin for early iron deficiency detection. A 2025 observational study demonstrated that Ret-He achieves superior diagnostic accuracy (AUC=0.839) compared to serum ferritin (AUC=0.728), with 81.7% sensitivity and 73.2% specificity at a cutoff of <23.6 pg. Unlike ferritin, Ret-He is not affected by inflammation (it does not rise as an acute-phase reactant), making it a more reliable marker in patients with chronic disease, infections, or elevated CRP. Ask your lab about this marker if you have inflammation-confounded ferritin results.