For years now people have used limes/lime juice to lighten their skin and even to get rid of pimples. Although there is no solid evidence which demonstrates that limes can help lighten the skin or treat acne, some people have claimed to get results by using it on their skin.
It is important to consider the fact that certain people can have an allergic reaction to lime juice when directly exposed to their skin, so you will want to be careful before trying it yourself.
Many people put lime juice directly on their skin just after tanning in order to intensity the effect that it has on them. There are certain acids in limes which could act to lighten the skin over time, though there is still no proof that this is the case.