Dark circles are the most commonly self-diagnosed skin complaint and the most commonly misdiagnosed one. Almost everyone assumes theirs come from not sleeping enough, buys something for them, and finds that nothing much changes. That is usually because the cause was never the one being addressed. Under-eye darkness has several distinct causes, they look broadly similar in a mirror, and they respond to entirely different things.
Two tests that sort most cases
The stretch test. Gently pull the skin at the outer corner of the eye sideways so the under-eye area is lightly stretched. If the darkness stretches with it and stays roughly as dark, it is pigment sitting in the skin. If it lightens noticeably, the colour is coming from underneath rather than from the skin itself.
The tilt test. Look in a mirror under overhead light, then tilt your head back or raise the light source. If the darkness largely disappears, you are looking at shadow cast by the shape of the face rather than at colour at all.
Between them, those two tests separate the four causes.
Pigment
True pigmentation under the eye is common in Indian and other deeper skin tones, often runs in families, and frequently extends beyond the under-eye into the eyelid or the sides of the nose. It also arrives from the same routes as pigmentation everywhere else: sun exposure on skin that is thinner than anywhere else on the face, and post-inflammatory darkening from rubbing, from eczema, or from years of allergic itching.
This is the only category where a topical product has a real role, and the expectations are the same as for pigmentation elsewhere: evening the look of marks, over months, with sun protection doing most of the work. What causes uneven skin tone applies here directly, and the under-eye is one of the most reliably under-protected areas of the face, as the sunscreen dosing post notes.
Blood vessels
Skin under the eye is the thinnest on the body, and the network of vessels beneath it shows through as blue, purple or reddish shadow. This is the type that worsens with tiredness, with dehydration, with crying, with allergies and during illness, since all of them affect circulation or fluid. It is also the type that genuinely improves with sleep, which is why the sleep advice works for some people and does nothing for others.
No cream changes vessel visibility in any lasting way. Cold compresses briefly constrict vessels, which is what the chilled spoon and the cucumber slice are actually doing, and the effect lasts about as long as the coolness does. If allergies are involved, managing the allergy does more than any eye product, because rubbing an itchy eye adds friction pigmentation on top of the vessel shadow.
Structure and shadow
With age and in some faces from youth, the fat pad under the eye shifts or the tear trough deepens, and the resulting hollow casts a shadow. This is a geometry problem, not a colour problem, which is why the tilt test makes it vanish. Nothing applied to the surface changes the shape of a hollow. The options that work here are in-clinic ones, and a good concealer is the honest daily answer for anyone not pursuing those.
Thin skin and general dullness
Skin that is dehydrated, crepey or simply thin reads as darker and more shadowed than it is, and this is the one category where a plain moisturiser genuinely improves the appearance within days. It is also the least dramatic cause and the most frequently improved by accident.
What to actually do
Work out which type you have before spending anything. If the stretch test says pigment, approach it as pigmentation: daily sun protection, a gentle tone-evening active given months, and no rubbing. If it lightens on stretching, you are looking at vessels, and the levers are sleep, allergy control and, occasionally, patience. If tilting the light removes it, no product is going to help and it is worth knowing that before buying five of them.
Two cautions specific to this area. The skin here is thin and reacts to actives that the rest of the face tolerates, so anything applied should be introduced slowly and patch tested first. And under-eye darkness that appeared suddenly, sits on one side only, or comes with swelling is worth a doctor's opinion rather than a cosmetic one.
Cham makes no eye product, so there is no recommendation waiting at the end of this. The only thing the range is relevant to is the first category, and only on the same slow terms as pigmentation anywhere else.
