PhenoAge
PhenoAge
A biological age estimate from nine markers plus chronological age, validated against mortality risk.
Osiro optimal≤ chronological years
Every biomarker we measure, what it tells you about your body, and what an optimal value looks like — written in plain language by our clinical team.
The composite that most people ask about first — an age estimate built from nine measured markers rather than a single number.
A biological age estimate from nine markers plus chronological age, validated against mortality risk.
The gap between your biological and chronological age — the number most people want first.
Cardiovascular and metabolic risk, including the particle-based measures a standard cholesterol panel leaves out.
The classic insulin-resistance index. Needs fasting insulin, so it is available only with that add-on — every panel includes the TyG index as standard instead.
The triglyceride-glucose index — our standard measure of insulin resistance, available on every panel and trackable over time.
Atherogenic Index of Plasma: the log of triglycerides over HDL, correlating with small dense LDL.
Every atherogenic fraction in one number. Total cholesterol minus HDL.
The balance between atherogenic and protective particles. Calculated from ApoB and ApoA1.
A direct count of the atherogenic particles that deposit in artery walls — a better predictor of cardiovascular risk than LDL cholesterol alone.
The main protein of HDL, reflecting the particles that carry cholesterol away from artery walls.
The cholesterol most people have heard of. Incomplete without a particle measure.
Cholesterol being transported away from tissues. Higher is generally better, though not without limit.
Circulating fat, strongly influenced by recent diet, alcohol and insulin resistance.
Total circulating cholesterol. Useful context, but far less informative on its own than ApoB.
Blood glucose at the time of the draw. Interpreted alongside HbA1c.
Fasting insulin. An optional add-on, and the input HOMA-IR requires.
Average blood glucose over roughly three months. The standard measure of glycaemic control.
Cholesterol in triglyceride-rich remnant particles, increasingly recognised as independently atherogenic.
Total cholesterol divided by HDL — a long-established composite risk ratio.
The ratio of atherogenic to protective cholesterol.
A simple, well-validated marker of insulin resistance.
Atherogenic coefficient — non-HDL cholesterol relative to HDL.
Your HbA1c expressed as an average glucose concentration, which many people find easier to picture.
Filtration, liver enzymes and two independent non-invasive fibrosis estimates.
A validated non-invasive estimate of liver fibrosis, from age, AST, ALT and platelets.
Estimated glomerular filtration rate — how effectively your kidneys filter. Calculated using CKD-EPI 2021.
A liver enzyme released when hepatocytes are stressed. The most liver-specific of the routine enzymes.
An enzyme found in liver and muscle. Read together with ALT rather than alone.
Sensitive to alcohol and bile duct irritation, and a useful marker of oxidative stress.
A muscle breakdown product cleared by the kidneys, and the main input to eGFR.
A purine breakdown product linked to gout and to metabolic and cardiovascular risk.
The main circulating protein — a marker of liver synthesis, nutrition and inflammation at once.
The principal extracellular electrolyte, central to fluid balance.
Tightly regulated and essential to cardiac and neuromuscular function.
An electrolyte used alongside sodium and bicarbonate to assess acid-base balance.
A nitrogen waste product reflecting both kidney function and protein intake.
Creatine kinase, released from muscle. Rises markedly after hard exercise.
Alkaline phosphatase, raised in both bile duct and bone activity.
A haem breakdown product. Mildly raised levels are often entirely benign.
Albumin plus globulins, giving a broad view of protein status.
Prostate specific antigen. A screening signal for trend monitoring, not a diagnosis.
Total protein minus albumin, largely reflecting immune proteins.
The AST to ALT ratio, which shifts in characteristic ways between different causes of liver stress.
AST to platelet ratio index — a second, independent fibrosis estimate.
The albumin-bilirubin score, a measure of liver reserve.
The urea to creatinine ratio, which helps distinguish dehydration from intrinsic kidney change.
Low-grade inflammation, plus ratio-based indices that a single CRP cannot show.
Neutrophil to lymphocyte ratio — a widely studied marker of systemic inflammatory balance.
Prognostic Nutritional Index, from albumin and lymphocytes — a measure of physiological reserve.
High-sensitivity C-reactive protein, detecting the low-grade inflammation linked to cardiovascular and metabolic risk.
Erythrocyte sedimentation rate — a slower, complementary inflammation marker.
Precursors of tissue macrophages.
Raised in allergy and certain parasitic conditions.
The rarest white cell, involved in allergic response.
The albumin to globulin ratio, which falls with chronic inflammation.
Platelet to lymphocyte ratio, another inflammation composite.
Lymphocyte to monocyte ratio, reflecting immune composition.
Monocyte to HDL ratio, linking inflammation and lipid metabolism.
Systemic Immune-Inflammation Index, from platelets, neutrophils and lymphocytes.
Systemic Inflammation Response Index, from neutrophils, monocytes and lymphocytes.
Neutrophils as a percentage of total white cells.
Lymphocytes as a percentage of total white cells.
Monocytes as a percentage of total white cells.
Eosinophils as a percentage of total white cells.
Basophils as a percentage of total white cells.
Full blood count with differential, and the red cell indices that classify anaemia.
Haemoglobin — the oxygen-carrying capacity of your blood.
Total white cell count — the headline measure of immune activity.
Cells responsible for clotting, and an input to both fibrosis scores.
The first-line responders of the immune system.
B and T cells — adaptive immunity.
Red cell count.
Haematocrit — the proportion of blood volume occupied by red cells.
Mean red cell volume, central to classifying anaemia.
Mean haemoglobin per red cell.
Mean haemoglobin concentration within red cells.
Variation in red cell size. A rising RDW is one of the stronger single predictors in the panel.
Mean platelet volume, reflecting platelet turnover.
The Mentzer index, which helps distinguish iron deficiency from thalassaemia trait.
Vitamin and mineral status, iron handling, and measures of physiological reserve.
25-hydroxyvitamin D. Insufficiency is common in the UK, particularly through winter.
Essential to nerve function and red cell production.
Works alongside B12 in methylation and red cell formation.
Stored iron. Also rises with inflammation, so read alongside CRP.
Circulating iron, which varies considerably through the day.
A cofactor in hundreds of enzymatic reactions, including glucose handling.
Central to immune function and wound healing.
Total circulating calcium, tightly regulated.
Total iron binding capacity — how much transferrin is available to carry iron.
Controlling Nutritional Status score, combining albumin, lymphocytes and cholesterol.
The percentage of iron-binding capacity in use. More stable than iron alone.
Unsaturated iron binding capacity.
Calcium corrected for albumin, which is the figure to interpret when albumin is abnormal.
Full thyroid function with antibodies, and a complete hormone picture including calculated free fractions.
The pituitary signal to the thyroid, and the most sensitive first-line thyroid test.
The active thyroid hormone at tissue level.
The main circulating thyroid hormone and precursor to T3.
Total testosterone, most of it bound to SHBG and albumin.
Sex hormone binding globulin, which determines how much testosterone is available.
The main stress hormone. Strongly time-dependent, so morning sampling matters.
An adrenal androgen precursor that declines steadily with age.
The unbound fraction, which is biologically active.
The principal oestrogen, relevant in both sexes.
Thyroid peroxidase antibodies — the commonest marker of autoimmune thyroid disease.
Thyroglobulin antibodies, a second autoimmune thyroid marker.
Total thyroxine, bound and free.
Free androgen index — testosterone relative to SHBG.
Free plus albumin-bound testosterone, calculated by the Vermeulen method.
The cortisol to DHEA-S ratio, sometimes used as a marker of adrenal balance.
The ratio of active to precursor hormone, reflecting peripheral conversion.
Measured results come directly from the laboratory. Calculated results are derived from measured values using published formulas — they are not extra tests and need no extra blood.
Osiro optimal bands are drawn from preventive and longevity literature and are deliberately narrower than a laboratory reference range, so a result flagged borderline here may still sit inside the laboratory’s normal range. Units are UK clinical units throughout.
Not every result appears in every panel — see the panel comparison for exactly what each includes.