Olive Healthcare is a South Korean company that makes handheld body scanners. Bello focuses on body fat and visceral fat estimates, while Fitto measures muscle at selected locations. Both connect to an app for tracking and fitness guidance.

How it works
The device shines several wavelengths of near infrared light into tissue beneath the skin. Fat, water and blood absorb the light differently. Software analyses the reflected signal from several locations and combines it with personal information to estimate fat, visceral fat, muscle mass or balance, depending on the product.

Key considerations
Results depend on consistent placement and technique. Skin, tissue thickness and the model can influence estimates, and readings from different body composition methods may not match. The devices are best used to follow trends under similar conditions.