One day a selfie might save your life.

Researchers are working on a way to check cholesterol levels with a smartphone, hopefully eliminating clumsy and complicated home cholesterol-testing devices.

Engineers in the US have created the Smartphone Cholesterol Application for Rapid Diagnostics, or “smartCARD,” which uses a phone camera to read cholesterol levels.

“Smartphones have the potential to address health issues by eliminating the need for specialized equipment,” said David Erickson, Cornell University associate professor of mechanical engineering and senior author on a new peer-reviewed study.

Relying on the most recent generation of tiny-but-powerful cameras, Erickson and his colleagues have created an accessory that optically detects biomarkers in a drop of blood, sweat or saliva.

A new app then discerns the results using colour analysis.

When a user puts a drop of blood on the cholesterol test strip, it processes the blood through separation steps and chemical reactions, before being assessed by the phone software.

The smartCARD accessory clamps over the phone's camera. It provides uniform, diffused light to illuminate the test strip that fits into the smartCARD reader, calibrates the hue saturation to the image's colour values on the cholesterol test strip, and displays the results on-screen.

An early version of the device is already available, but researchers are not resting.

They are developing enhanced versions that can detect different kinds of cholesterol as well as measure other aspects of the blood including Vitamin D levels and triglyceride.

Details of the most recent study are available here.