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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The brain is the command center of the entire body. Weighing roughly 1.4 kg, it coordinates every thought, movement, sensation, and autonomic process — from heartbeat regulation to memory consolidation. It consumes approximately 20% of the body's total energy despite representing only 2% of body weight, making it uniquely sensitive to nutrient availability, blood flow, and oxidative stress. Cognitive decline is not inevitable with age; it is largely driven by modifiable factors that can be tracked with blood tests and supported with targeted nutrition.
These blood tests reveal nutrient deficiencies and metabolic imbalances that directly impair brain function, often long before symptoms appear.
| Test | What It Detects | Link |
|---|---|---|
| Homocysteine | Elevated levels indicate poor methylation and increased risk of brain atrophy and dementia | Lab Tests |
| Vitamin B12 | Deficiency causes neuropathy, cognitive decline, and impaired myelination | Lab Tests |
| Folate (B9) | Essential methylation cofactor; deficiency raises homocysteine and impairs DNA repair | Lab Tests |
| Magnesium (RBC) | Intracellular magnesium status; deficiency impairs synaptic transmission and sleep | Lab Tests |
| Omega-3 Index | DHA as percentage of RBC membranes; low levels correlate with accelerated cognitive decline | Lab Tests |
| TSH | Thyroid dysfunction causes brain fog, depression, and cognitive slowing | Lab Tests |
| Cortisol | Chronic elevation damages hippocampal neurons and impairs memory consolidation | Lab Tests |
These supplements target distinct aspects of brain health: neurotrophic support, structural membrane integrity, neurotransmitter balance, and cellular energy.
| Supplement | How It Helps | Link |
|---|---|---|
| Lion's Mane | Stimulates NGF synthesis; promotes neurogenesis, myelination, and synaptic growth | Lion's Mane |
| Magtein (Mg L-Threonate) | Only magnesium form proven to cross the blood-brain barrier; enhances synaptic density | Magtein |
| L-Theanine | Increases alpha brain waves (8-12 Hz); promotes calm, focused attention without sedation | L-Theanine |
| Omega-3 DHA | Primary structural fatty acid of neuronal membranes; 60% of brain fat is DHA | Omega-3 |
| B-Complex (Methylated) | Methylation cofactors for neurotransmitter synthesis; reduces homocysteine, prevents brain atrophy | B-Complex |
| NMN | NAD+ precursor supporting neuronal energy metabolism and DNA repair in aging brains | NMN |
| Creatine | Increases brain phosphocreatine reserves; improves cognition under fatigue and sleep deprivation | Creatine |
Blood-based Alzheimer's biomarkers reach clinical use. In May 2025, the FDA cleared the first blood test to diagnose Alzheimer's disease — the Fujirebio assay measuring phospho-tau 217 and amyloid-beta 42/40 ratios, showing >91% agreement with PET brain scans. A second test (Roche Elecsys) was cleared in October 2025 for primary-care use, enabling earlier, non-invasive detection years before symptoms. This transforms screening from expensive PET imaging to a routine blood draw, making it relevant for anyone tracking brain health proactively.
Brain age gap validated as a predictive biomarker. A 2025 Communications Medicine study established the brain age gap (BAG) — the difference between MRI-estimated brain age and chronological age — as a clinically useful biomarker for neuropsychiatric risk stratification. Healthier lifestyle interventions (exercise, sleep quality, stress management) were shown to significantly reduce accelerated brain aging, providing a measurable target for neuroprotection strategies.