Field notes
from the body.
Reading your body between the blood draws: where a standard panel falls short, and what your wearables add once everything sits on one timeline.
Approach 
How to Combine Wearable Data with Blood Work: A Complete Guide
A step-by-step guide on how to combine wearable data with blood work: baseline your HRV, RHR, sleep and glucose, pick the right panel, and read them as one.
Raghav Dua Latest
Science Why doctors don't test fasting insulin
Why don't doctors recommend fasting insulin tests? The honest answer: guidelines, reimbursement, and assay variability target glucose and HbA1c instead.
Prithvish Baidya 
Science Why don't doctors test ApoB yet?
Why don't doctors test ApoB? The standard panel, guideline lag, and Medicare's LDL-C rules explain the gap — and why a single ApoB draw still matters.
Prithvish Baidya 
Product The best at-home blood test for longevity markers
The best at-home blood test for longevity markers isn't the one with the most markers. The six that move first, and how to choose a panel that reads them well.
Prithvish Baidya 
Product Introducing the Founders Edition
The first 1,000 people to join Depth become Founders: a numbered card, a free Recap on day one, and first access to everything that ships after.
Raghav Dua 
Product AI health coach for your wearable data
An AI health coach for wearable data reads your Oura, Apple Watch and CGM together, explains why a number moved, and tells you the one thing to change.
Raghav Dua 
Product The app that tracks your blood biomarkers and fitness-tracker data together
Most apps track blood biomarkers or fitness-tracker data, never both. Here's what an app that reads labs and wearables on one timeline should do.
Raghav Dua Science 6
See all Science Why doctors don't test fasting insulin
Why don't doctors recommend fasting insulin tests? The honest answer: guidelines, reimbursement, and assay variability target glucose and HbA1c instead.
Prithvish Baidya Science Why don't doctors test ApoB yet?
Why don't doctors test ApoB? The standard panel, guideline lag, and Medicare's LDL-C rules explain the gap — and why a single ApoB draw still matters.
Prithvish Baidya 
Science Why low ferritin drains you when sleep is good
Wondering why your ferritin is low but sleep is good and you're still tired? Low iron stores sap energy before anemia shows. The thresholds and what to do.
Prithvish Baidya Product 7
See all Product The best at-home blood test for longevity markers
The best at-home blood test for longevity markers isn't the one with the most markers. The six that move first, and how to choose a panel that reads them well.
Prithvish Baidya Product Introducing the Founders Edition
The first 1,000 people to join Depth become Founders: a numbered card, a free Recap on day one, and first access to everything that ships after.
Raghav Dua Product AI health coach for your wearable data
An AI health coach for wearable data reads your Oura, Apple Watch and CGM together, explains why a number moved, and tells you the one thing to change.
Raghav Dua Approach 3
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Approach Why continuous monitoring beats the annual physical
An annual physical measures you for fifteen minutes once a year. Your body changes faster than that. Continuous monitoring watches the drift between readings.
Raghav Dua 
Approach Your body is a time series: reading labs and wearables over time
Reading your labs and wearables one at a time treats your body as a still photo. Read as a trend over time, the signal is in the motion between frames.
Prithvish Baidya 
Approach Normal HbA1c but rising? Why the trend beats the threshold
A threshold tells you when you've already crossed a line. A trend tells you you're heading for it, while there's still time to turn.
Raghav Dua