Dark circles under the eyes develop through a combination of genetics, lifestyle habits, and structural changes in the face that become more pronounced over time. The skin beneath your eyes is only about 0.5 mm thick, making it one of the thinnest areas on your body. That thinness means anything happening underneath, from swollen blood vessels to lost volume, shows through more visibly than it would anywhere else on your face.
The Four Types of Dark Circles
Not all dark circles look the same because they don’t all form the same way. Dermatologists generally classify them into four categories based on what’s driving the discoloration, and knowing which type you have matters if you ever want to treat them.
Pigmented: Excess melanin deposits in the skin around the eyes, creating brown or grayish patches on the upper eyelids, lower eyelids, or both. This is the most common type in people with deeper skin tones (Fitzpatrick types V and VI) and often runs in families.
Vascular: Blood vessels beneath the thin under-eye skin become visible, producing a bluish or purplish tint that’s most noticeable along the inner lower eyelid. Studies of lighter skin tones found this is the most common form, accounting for roughly 42% of cases in one Chinese population study. Reduced oxygen saturation in those small vessels makes the color appear even darker.
Shadow-related: Structural features like a deep tear trough, puffy fat pads, or an overhanging eyelid muscle cast shadows that mimic discoloration. This type changes depending on the angle of the light and tends to worsen with age.
Post-inflammatory: Chronic rubbing, scratching, or skin conditions like eczema leave behind irregular brownish or gray patches from inflammation-driven pigment changes.
Most people have a mix of two or more types happening at once.
Genetics and Skin Tone
If your parents had dark circles, you’re likely to develop them too. Constitutional hyperpigmentation, the medical term for genetically determined under-eye darkening, is one of the most common causes worldwide. Some people are simply born with more melanin-producing cells around their eyes, and no amount of sleep will change that baseline.
Skin tone plays a significant role in which type of dark circle you’re predisposed to. In populations with deeper complexions, excess pigmentation dominates. In people with lighter skin, visible blood vessels are more often to blame because less melanin means less camouflage over those tiny veins and capillaries. The structural anatomy of your face also has a genetic component: the depth of your tear trough, the thickness of your skin, and the size of your orbital fat pads are all inherited traits.
How Aging Changes the Under-Eye Area
Your face loses volume and structural support as you age, and the under-eye area is one of the first places this becomes visible. The main forces at work are gravity, skeletal remodeling, loss of subcutaneous fat, hormonal shifts, cumulative sun exposure, and smoking. Together, these create a cascade of changes that deepen dark circles year by year.
The infraorbital fat pads, the small cushions of fat that sit beneath your eyes, behave unpredictably with age. In some people they thin out, creating a hollow tear trough that runs from the side of the nose down across the cheek. That hollow catches shadows and makes the area look sunken and dark. In others, particularly after age 50, those fat pads shift forward and downward, creating puffy bags that cast their own shadows. The density of the fat also decreases over time, making the tissue less firm even as its total volume may actually increase.
Collagen loss thins the skin further, making underlying blood vessels even more visible than they were in your twenties. Sun damage accelerates this process by breaking down both collagen and elastin while simultaneously triggering extra melanin production.
Allergies and Nasal Congestion
The dark, puffy semicircles that appear during allergy season have their own name: allergic shiners. They form through a surprisingly mechanical process. When your immune system reacts to an allergen, the moist lining inside your nose swells. That swelling compresses the veins that drain blood from the sinus cavities near your eyes. Since those veins sit close to the surface of the thin under-eye skin, the backed-up blood makes the area look darker and puffier.
Itchy, watery eyes make things worse because rubbing the skin introduces friction that triggers post-inflammatory pigmentation over time. Chronic allergies, asthma, and atopic dermatitis all contribute to persistent dark circles through this combination of vascular congestion and repeated mechanical irritation.
Sleep, Screens, and Daily Habits
Even one or two nights of poor sleep can produce noticeably darker circles. Sleep deprivation causes blood vessels to dilate, and the thin under-eye skin doesn’t hide that extra blood flow well. It also makes your skin paler overall, which increases the contrast between your complexion and the darkened area below your eyes.
Extended screen time contributes in a different way. When you stare at a screen, your eyes constantly refocus on the tiny pixels that make up the text and images. That sustained effort strains the muscles around your eyes and can increase blood flow to the area, producing aching and visible congestion. The effect compounds if you’re also staying up late because of your screen use.
Dehydration is another common trigger. When your body is low on water, the skin loses plumpness and the under-eye area looks more hollow and shadowed. This is especially noticeable in the morning if you haven’t been drinking fluids for several hours.
Alcohol’s Effect on Under-Eye Skin
Alcohol worsens dark circles through several overlapping pathways. It stimulates histamine release, which dilates blood vessels under the skin and can make your complexion look flushed or inflamed. Under the eyes, those dilated vessels show through as a darker, more congested appearance.
Alcohol also disrupts sleep architecture. Even if you fall asleep easily after drinking, the quality of that sleep is lower, and the resulting under-eye darkening is the same as what you’d see after a night of insomnia. Over the long term, heavy alcohol use can damage the liver, and liver conditions like hepatitis or cirrhosis are associated with darker skin around the eyes as a secondary symptom. The dehydrating effect of alcohol pulls moisture from your skin as well, making the area look thinner and more translucent.
Iron Deficiency and Other Medical Causes
When your body doesn’t have enough iron, red blood cells carry less oxygen to your tissues. The under-eye skin, already thin and translucent, responds by looking paler or more washed out, which makes the small blood vessels underneath stand out more sharply. The result is a tired, darkened appearance that doesn’t improve with rest.
Other medical conditions linked to dark circles include thyroid disorders, which can cause puffiness and skin changes around the eyes, and kidney problems, which affect fluid balance and can create persistent swelling. Certain medications that dilate blood vessels or cause fluid retention can also make under-eye darkness more pronounced.
Why Some People Develop Them Earlier
Dark circles aren’t strictly an aging concern. Teenagers and young adults develop them too, especially when genetics, allergies, and lifestyle factors overlap. A person with naturally deep-set eyes, a family history of hyperpigmentation, seasonal allergies, and a habit of staying up late on screens has multiple contributing factors stacking on top of each other.
The key insight is that dark circles are rarely caused by a single factor. They’re almost always the visible result of several overlapping mechanisms: some you can control, like sleep and hydration, and some you can’t, like bone structure and inherited pigmentation. Understanding which factors are driving yours is the first step toward knowing which ones are actually worth trying to change.