If someone tried to sell you a smart belt, you might roll your eyes and mumble something about consumer technology flying off the rails. But Welt, a product incubated in Samsung's C-Lab program, is one of the smartest wearable health-tracking products yet.

First announced a year ago, Samsung C-Lab's Welt tracks one of the most important health metrics: waist size. Numerous studies have shown the size of your midsection can predict the risk of heart disease, diabetes and hypertension. While other health-focused wearables track stats like daily steps and heart rate – handy for seeing how much exercise you're getting, but not much else – Welt goes straight for this key predictor.

I tried Welt at CES and find the idea to be simple and profound. Magnetic sensors in the buckle measure the size of your waist. It tracks changes in waist size over time and can make you more aware of bad eating habits or even minor waist gains (it can notify you if you've eaten a big meal and are bulging out a bit more).

Fortunately it doesn't look like the frighteningly-geeky images that the term "smart belt" may conjure: Apart from a charging port, it looks just like a regular, classy belt, and is sold in a variety of styles.

Welt doubles as a standard fitness tracker, logging your daily steps (it tracks any session of 20 or more steps), as well as idle time (sitting or lying) and estimated calories.

The company says the belt's battery lasts 20 days, and it recharges in an hour via microUSB when you need to juice up.

I was intrigued enough by the importance of waist measurements that I took home a Welt from the C-Lab booth to use longer-term: Check back later for a full review.

Welt is up for pre-order for either $149 or $199, depending on the design you choose.

Product page: Welt

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