As a physicist, and not a physician, I'd say that the answer depends on the wavelength of light. It's more opaque to red light and more translucent to blue, at least the outer layers.
Light can pass through your body if it's bright enough, like making your fingers glow if you turn on your phone's back LED and put your finger over it. So it's translucent, just very close to opaque.
Skin isn't 100% opaque, it makes your hand or finger glow on certain objects and the insides of your eyelids red if you looking at the light with your eyes closed.
As a physicist, and not a physician, I'd say that the answer depends on the wavelength of light. It's more opaque to red light and more translucent to blue, at least the outer layers.