Does that mean where more light is behind the subject? I noticed that on a couple but didn't realize they were all that way. Is this a bad thing or just a "thing"?
Generally, you want a person's face to be the best lit and most contrasted part of a portrait type photo. Backlit people do not exhibit this characteristic. Shooting in direct sunlight is pretty much a bad idea. On a bright sunshiny day, try to find a spot of shade and then use a flash to illuminate your subject's face.
results should be similar to this:
It isn't overly dramatic lighting, but you don't want harsh light from the sun to be your only light source, generally.