Does touching your nose make it bigger over time?

Hello and thanks for your question.Trauma or pulling and stretching ligaments and supporting tissue can affect it, but the most important factor is genetics. The underlying structures of cartilages and bone as well as skin can affect the shape. After nasal surgery you should limit touching your nose. Cleaning the nose or scratching it lightly would be ok.Best wishes,Dr Sajjadian

The human tissues do "adapt" its shape to changes in force however this cannot be applicable to the nasal framework. The nasal bones and too strong to be changed by forced while the cartilages are flexible and have a memory. Pushing on your nose does not change the shape of it permanently. The only thing that does is a surgical rhinoplasty procedure.
Hope this helps,Ali Rıza Öreroğlu, MD FEBOPRASEuropean and Turkish Board Certified Aesthetic, Plastic and Reconstructive SurgeonIstanbul, Turkey

Normal manipulation of the nose doesn’t have an impact upon either its size or shape. This only occurs with significant trauma. Throughout life the nose is constantly exposed to mechanical forces, despite this its appearance doesn’t change. For this reason, changes in the size and shape of the nose usually always require some type of surgical intervention. 

There have not been any studies of this that I know of so no one can say for sure. A nasal fracture can cause a bump on the nose. Also, the tip of the nose is connected to the septum by ligamentous tissue that can weaken over time. It is possible that constant pulling on the tip might weaken this tissue further.

Hello,
Everyday minor picking, stretching, and itching does not affect your nose. Genetics and intense trauma and contact can alter the shape of your nose. Also the nose and ears are the only body parts that don't stop growing due to the cartilage inside of each. 
All the best!
Deepak Dugar, MDScarless Rhinoplasty ExpertBeverly Hills, CA 90210

The effects of gravity on the face do not spare the nose, and many people experience a longer nasal appearance with aging, Gravity persistently pulls the tip of your nose down, along with many other facial soft tissues. Manual downward force on the tip of your nose may stretch the ligaments from your bridge to your tip leading to a bigger appearance.Hope this helps.Dr Joseph