I found this among a few others while researching. This in response to a woman asking about her husband's dark eye circles.
http://www.bbc.co.uk/health/ask_doc...rkcircles.shtml
Three things contribute to dark rings under the eyes:
an inherited tendency
natural aging processes, and
lack of sleep.
There's not much you can do about the first two of these.
Ageing thins the skin
As we get older the skin gets thinner, due to break down of the 'scaffolding' formed by collagen fibres and weakening of the elastic fibres which keep the skin taut.
The thinning of the skin is particularly noticeable in certain parts of the body, especially those areas where the skin is stretched over bony structures without thick layers of fat and other tissues beneath. The skull is typical, especially around the eyes. Another place is the back of the hands, which often look darker with age.
There isn't room for fatty layers around the eye sockets because this would get in the way of our ability to move our eyes and see. So skin around the eyes is thin and gets thinner with age - allowing the blood vessels and darker shadows of bone to show through.
To some degree this process is again controlled by our genes and family patterns, but it is also influenced by things which damage the skin such as too much Ultraviolet A light (UVA), or smoking.
It's usually women who are more aware of the damage that smoking does to their skin but if your husband smokes, this could be contributing to his dark circles.
Lack of sleep
Lack of proper restful sleep also cause dark rings for reasons which are not properly understood, but which may be related to skin and blood supply changes in the area.
A difficult problem to tackle
There is very little that can be done about dark rings, other than getting as much sleep and rest as possible. This may mean taking a serious look at your work and sleep habits, including not just the amount of sleep - but the quality of it too. Is sleep interrupted, especially by snoring or waking episodes? Do you get enough sleep, especially at the right times of the night for you?
Beauty treatments
Various beauty products or complementary therapies are claimed to have miraculous powers on tired baggy eyes - but I remain somewhat cynical. Neither can cosmetic surgery offer much to help treat thin skin.
I have a couple of female friends who are leading lights in the beauty world and both of them have dark circles under their eyes. They acquired them with age and have failed to remedy the problem despite throwing every trick in the book at them.
There is one cosmetic - a liquid-like foundation - which does help because it contains titanium powder which reflects light across the dark area. TV make-up people swear by it, so perhaps it might be worth having a word with your local beauty counter.