For clinicians
Reference guide
The reference values behind every verdict in the report, by domain.
Biological age
How biological age is estimated and weighted.
Brain
Markers for cognition and the nervous system.
Heart
Blood pressure, lipids and cardiovascular risk.
Hormones
Thyroid, sex hormones and menopause: TSH and FT4, cycle, PCOS features, bleeding and iron, menstrual pain, PMS and the six transition factors.
Metabolism
Blood sugar, insulin and liver values.
Nutrients
Vitamins, minerals and their optimal range.
Lifestyle
The reference values behind the lifestyle scores: nutrition, movement, sleep, stress and substance use.
Biomarkers
Every factor Synapse measures: per domain, with unit and sources.
This list comes straight from the same source as the report; guide and report cannot contradict each other.
The colour zones are personal: they depend on age, sex, risk and history, and appear in the patient's own report.
Biological age is a house-weighted, motivating estimate, not a validated clock.
Heart & circulation
| Factor | Unit | Sources |
|---|---|---|
| Cholesterol | mg/dL | |
| LDL cholesterol | mg/dL | ESC/EAS 2019: dyslipidaemia guidelines · European Heart Journal 41(1): 111–188 |
| HDL cholesterol | mg/dL | |
| Triglycerides | mg/dL | |
| ApoB | mg/dL | ESC/EAS 2019: ApoB as the primary measure in discordance · European Heart Journal 41(1): 111–188 |
| Lp(a) | nmol/L | EAS 2022: consensus statement on lipoprotein(a) · European Heart Journal 43(39): 3925–3946 |
| hsCRP | mg/L | AHA/CDC 2003: hs-CRP and cardiovascular risk · Circulation 107(3): 499–511 |
| Ferritin | μg/L | |
| Creatinine | mg/dL | |
| Uric acid | mg/dL | |
| Albumin/creatinine ratio (ACR) | mg/g creatinine | |
| Hemoglobin | g/dL | |
| Hematocrit | % | |
| White blood cells | /μL | |
| RDW (red-cell distribution width) | % | |
| Platelets (thrombocytes) | 10^3/μL | |
| Vitamin B12 | pg/mL | |
| Folic acid | ng/mL | |
| Iron | μg/dL | |
| Transferrin saturation | % | |
| MCV | fL | |
| eGFR (CKD-EPI) | mL/min/1.73m² | KDIGO 2024: CKD guideline (CKD-EPI 2021) · Kidney International 105(4S) |
Metabolism
| Factor | Unit | Sources |
|---|---|---|
| Hemoglobin A1C | % | ADA 2025, Standards of Care: glycaemic criteria · Diabetes Care 48(Suppl. 1) |
| Glucose | mg/dL | ADA 2025, Standards of Care: fasting glucose · Diabetes Care 48(Suppl. 1) |
| Insulin | μU/mL | |
| HOMA2-IR (insulin resistance) | ||
| ALT (GPT) | U/L | |
| AST (GOT) | U/L | |
| GGT | U/L | |
| ALP | U/L | |
| Albumin | g/L |
Brain
| Factor | Unit | Sources |
|---|---|---|
| Homocysteine | μmol/L | |
| Vitamin D | ng/mL | Endocrine Society 2011: vitamin D deficiency · JCEM 96(7): 1911–1930 |
| Magnesium | mmol/L |
Hormones
| Factor | Unit | Sources |
|---|---|---|
| TSH | mU/L | |
| FT4 | pmol/L | |
| Cortisol | μg/dL |
Insights to discuss with the patient, not a diagnostic instrument.