Tests & Topics
What I use in practice.
And what each test actually tells you.
A plain-English guide to the investigations and concepts I use with patients. Nothing here is a sales page — these are educational explainers so you can decide, with your own doctor, which ones are actually worth your time and money.
Measurement tools I find most useful
Most of modern preventive medicine is just measurement plus interpretation. You can't manage what you don't measure, but you also don't need to measure everything. Below are the tests I find genuinely useful, in rough order of how often I order them.
A proper blood panel
ApoB, Lp(a), fasting insulin, HbA1c, GGT, ALT, TSH, ferritin, vitamin D, B12. Not just "cholesterol." The actual risk markers, ordered once and tracked over time. Cheapest, highest-yield test most people aren't getting.
VO2max & CPET
Cardiopulmonary exercise testing measures the maximum oxygen your body can use during hard exercise. It is one of the strongest single predictors of all-cause mortality in adults. Worth knowing your number; worth working to raise it.
DXA body composition
The gold standard for fat, lean mass, and bone density. Tells you what the scale and BMI cannot — how much muscle you actually have, where your visceral fat is, and whether your bones are starting to thin.
FibroScan (liver)
A 10-minute ultrasound-like scan measuring liver stiffness and fat. Catches early fatty liver and fibrosis long before blood tests flag anything. Useful for anyone who drinks, has metabolic risk, or simply wants a baseline.
Biological age testing
DNA methylation clocks (like GrimAge, LinAge, BeyondClock) and other multi-omic measures. Still a developing field — I use them as a motivational tracker and directional signal, not a diagnosis.
Gut microbiome analysis
Stool metagenomics (GI-MAP and similar). Most useful in people with persistent GI symptoms, recurrent courses of antibiotics, or as a baseline before a structured gut intervention. Less useful as a routine screen.
Cardiovascular risk scoring
PREVENT 2023, QRISK3, coronary artery calcium (CAC) scoring. Puts your blood pressure, lipids, family history and lifestyle into one meaningful number — far more useful than any single marker alone.
Genomic profiling
NalaGenetics, nutrigenomic and pharmacogenomic panels. Most useful for people with strong family histories, medication reactions, or specific questions about drug metabolism and nutrient needs.
HRV & wearable data
Continuous heart rate variability (Oura, WHOOP, Apple Watch). The cheapest, most accessible stress and recovery marker. Track your trend, not your absolute number.
Where this fits
I see patients in a longevity and preventive-health setting at Raffles HealthyLongevity. If you're interested in any of these tests, the right first step is a proper consultation with your own doctor to decide which are worth doing for your situation, what order to do them in, and how to act on the results. No test in isolation tells the full story.
Individual explainers for each test are coming. In the meantime, the blog has in-depth articles on several of these — browse the writing.