Apple has long been rumored to be working on noninvasive blood glucose monitoring. Now, a Bloomberg report says the company tested an app that helps people with prediabetes better manage their condition.

Citing anonymous Apple sources, Bloomberg notes the app required Apple employees to validate they were prediabetic via a blood test. Employees then monitored their blood sugar using “various devices available on the market” and logged changes related to what food they were eating.

Prediabetes is a metabolic condition when blood sugar levels are higher than normal, and increases a person’s risk of developing Type 2 diabetes. And while there is no cure for diabetes, prediabetes can be reversed through diet and exercise interventions. The idea for an app like this would be to show people how different choices can impact blood sugar levels. For example, a carb-heavy meal might spike blood sugar, but pairing the same meal with protein can blunt the spike.

The report notes that the app was intended to investigate what tools Apple could develop using blood sugar data. However, Bloomberg also says that Apple has since paused work on the app to focus on other health features. Even so, it’s possible that Apple will use its findings in future health tech offerings.

On a larger scale, metabolic health tracking is a burgeoning wearable trend. Earlier this year, Dexcom and Abbott both released over-the-counter CGMs that were aimed at prediabetic, non-diabetics, and Type 2 diabetics who don’t use insulin. There are also continuous glucose monitor (CGM) startups, like Nutrisense and Levels, that use CGM data to help people lose weight, fuel for endurance sports, or learn about how certain foods impact their blood sugar levels.

Given all that, it’s not surprising to hear Apple is interested in exploring this area. For starters, it’s largely shied away from native food logging while also increasing third-party CGM integrations. Apple itself has reportedly spent roughly 15 years tinkering on how to noninvasively monitor blood glucose, though that project is still likely years away from completion.