Our core proven method: doubly labeled water.

O is expelled from the body faster because it is washed out by both H2O and CO2, while H is flushed out solely by H2O. The resulting difference between expulsion rates is total calories burned over the course of the test (CO2 production rate).

Using safe and natural stable isotopes, Calorify traces how hydrogen and oxygen leave the body in order to measure cellular respiration (when cells turn food into energy). This measure is equal to the number of calories burned by the body during the test period (Westerterp 2017).

Our lab quantitatively measures how much CO₂ you produce. This is the only way to measure calories in a real-world setting.

The Tech

We make our measurements using off-axis integrated cavity output spectroscopy (OA-ICOS).

This technology allows us to achieve incredible precision and accuracy while keeping costs low and throughput high compared to traditional methods (Berman et al. 2012; Melanson et al. 2018).

The Kit

“It’s as simple as a sip of water”

The testing process is simple, consisting of a single a sip of doubly labeled water and the collection of three urine samples over the course of a week - all from home, with no lab visits required. Here’s a quick how-to video and FAQs for more info.

Urine samples are taken before being dosed with DLW (A), 4-6 hours after drinking the DLW (B), and 7 days later (C).

The Science