Eli5: How do body composition scale works? How does it know how hydrated am I and based on what does it know how much body fat do I have?



Obviously, you have to enter some data about yourself, but does it have some kind of “perfect body template” based on BMI?
And how does hydration info work?

In: Technology

The ones I have used use a small electrical current measuring the resistance as it travels through muscle, fat, organs, bone and from there it can break each amount of resistance down into percentages.

How hydrated you are affects the electrical current as well.

I’m by no means an expert, that’s just how I’ve been led to believe it works.