Not really, routinely we often see bgray sunglasses, that's because this color best block the glare from the sun, thus reducing the intensity of the sun and visually diminishing the light. But most of these other colors sunglasses also have the effect of the same function, why don't you try it?
This should need to be based on the degree of sunlight you are often in a relationship, a long time in the hot sun environment, of course, it is recommended that dark 80% gray sunglasses, and mild summer street suitable for wearing light-colored gray sunglasses, while shading the sun can better show themselves.