Feature: Add option that can hide activities.

[OMSmolina]

Add the option to hide the activities for those of us who want to see only what is related to nutrition (Meals, weight, fasting, water) since we use another application for the activities.

[lajawi]

But for the nutrients to be calculated according to how active you were, you'd still need to somehow add the data from those other applications, and, as far as I know, it's not currently possible to set it up to automatically read that data from the health apps on Android and iOS (which links up to issue #103).