Do variegated plants need more light?

Short answer: Yes!

Long answer: Yes -- because...

We all know -- or, at least, we all should know -- that plants create energy using the energy found in light, using something called chlorophyll -- and very likely, you remember that chlorophyll is green! 

There are other chemicals that are present in plants that create the wide array of colours found in nature; some are there purely to attract pollinators, and some have added benefits -- like, for example, leaves often come in red or pinkish because those pigments actually reflect UV light, which can harm the sensitive new leaf! (This isn't the ONLY way to have variegation, but it's the most common.)

So -- the more green that a leaf has, the more chlorophyll is at the surface of the leaf, and the more energy it can absorb from the light. More variegation, less chlorophyll -- so less energy absorbed, and more light needed!