Over 10 years a person's physical appearance can change significantly. Add in the potential of a significant weight loss, changes in hair colour, removal or addition of facial hair and the natural aging process and the result is you don't look much like the photo in your passport.

The Canadian government recommends you should get a new passport if your appearance has "changed a lot" but doesn't define what a "lot" happens to be. Do other countries have similar recommendations?

Have you renewed your passport because of a change in appearance and how significant was the change? Have you ever had a change in appearance cause an issue either entering a different country or returning to your own?