The demand on developing greener sensing systems have caused a need to find alternative materials that could save fossil-based materials and/or prevent the pollution of earth. Typically, cellulose materials roles have been acting as a passive support element or a porous matrix that causes a liquid flow in the diagnostic test. In this work, we present three novel approaches to utilize cellulose in medical and environmental sensing systems where cellulose is in an active form. (1) Cellulose based optical fibers enable to use the fibers as an active detection element that is not possible with traditional plastic and silica materials. The cellulose fiber can sense environmental changes around the fibre allowing to use it in respiratory and touch sensing. (2) Transparent cellulose nanofibril (CNF) film is sensitive to changes in environmental conditions. When the film is patterned with nanolithography imprinting (NIL) the film creates a diffraction pattern, when a laser beam is shot through the film. The dimensions of pattern can be used to non-contact environment sensing systems. (3) Stretchable cellulose nanofibril (CNF) film enables to prepare wearable electronics systems for medical testing. The electronic components of the test can be collected after removing the organic materials by composting. The study demonstrates the versatility of cellulose materials on medical and environmental sensing systems.