What a tear trough actually is
The tear trough is the groove that runs from the inner corner of the eye diagonally down towards the cheek. It marks the junction between the lower eyelid and the mid-face, where the skin is tethered to the bone beneath by ligaments.
That tethering is why the area forms a defined line rather than a gentle slope. When the tissue on either side of it loses volume, the tethered point stays put and everything around it drops away, so the groove becomes deeper without anything having been removed from the groove itself.
Where the groove is pronounced enough to be a recognised feature rather than a shadow, it is sometimes called a tear trough deformity, which sounds more alarming than it is. It describes an anatomical arrangement, not a problem.
Genetics: why some people have them at 20
Facial anatomy is largely inherited, and some people simply have less soft tissue support along the infraorbital rim, or a more prominent bony edge beneath the eye, or ligaments that sit slightly differently.
Those people often have visible under eye hollows in their twenties, long before ageing has contributed anything. It is why two people of the same age, in the same health, with the same sleep pattern, can have completely different under eye appearances.
If you have had hollow eyes for as long as you can remember, and photographs from childhood show the same thing, the cause is structural rather than anything you are doing.
Ageing: why they deepen over time
From the mid-thirties onwards, several things happen at once.
Bone recedes. The orbital rim gradually resorbs, widening the eye socket and removing support from beneath.
Fat redistributes. The pads of fat that cushion the mid-face lose volume and descend, so the cheek no longer meets the lower lid as smoothly as it did. In some people the orbital fat behind the eye also pushes forward, which produces a bulge above the hollow rather than filling it.
Muscle and ligaments slacken. The orbicularis oculi loses tone and the retaining ligaments weaken, which lets the whole area settle downwards.
None of these happen dramatically. It is the accumulation over a decade that turns a faint line into a hollow under eyes that is visible across a room.
Skin thinning and quality
The skin beneath the eye is the thinnest on the body, and it gets thinner.
As collagen production slows and skin elasticity declines, the skin loses its ability to bounce back and starts to show what is underneath it. Blood vessels become more visible through it, which is a significant contributor to dark circles, and fine lines develop where the skin creases.
This is the one element of the problem that responds to treating the skin itself. Medical-grade skincare, polynucleotides and similar skin-quality treatments can improve skin texture and thicken the tissue. What they cannot do is replace structural support, which is why creams disappoint anyone whose hollow is a volume problem.
Why they look worse on some days than others
This is the part most articles skip, and it explains a great deal of the confusion.
Day-to-day factors do not create a tear trough. They change how visible the one you already have appears to be.
- Sleep. Poor sleep affects circulation and fluid distribution in the face, which deepens the shadow without deepening the hollow.
- Dehydration. Reduces the fullness of the tissue, so an existing hollow reads as more pronounced. This is why sunken eyes are one of the more recognisable signs of being significantly dehydrated, and why they resolve within a day of correcting it.
- Salt and alcohol. Both shift fluid around, often producing puffiness above the trough that increases the contrast.
- Allergies and sinus problems. Congestion in the veins around the eye darkens the area noticeably.
- Illness. Short-term changes in fluid and circulation do the same thing.
There is one exception, and it is worth knowing about. Significant weight loss genuinely does create hollowing, because the fat pads of the face are among the first places the body draws from. Sunken eyes and under eye hollowing after rapid weight loss are not an illusion of light and shadow, and they do not recover when you rehydrate.
If your under eye appearance has changed quickly, that is worth mentioning at consultation, because a rapid change usually has a different explanation from a gradual one.
Light and shadow: the part nobody explains
Tear troughs are as much an optical effect as an anatomical one.
The hollowness itself may be a few millimetres deep. What you see is the shadow it casts, and how dark that shadow reads depends entirely on how light falls across the face.
This is why the area looks worse under overhead lighting, in a bathroom mirror and in phone photographs taken from below, and better in soft or diffuse light. It is also why some people are troubled by hollows that are objectively very slight, and others are untroubled by deeper ones.
In many cases the useful question is not how deep the hollow is, but how much contrast it creates. That distinction matters, because contrast can sometimes be reduced without adding any volume at all.
Tear troughs and under-eye bags are not the same thing
The two get confused constantly, and they have opposite causes.
A tear trough is a loss of volume, a groove, a shadow. An under-eye bag is an excess: orbital fat bulging forward, fluid, or skin laxity sitting in a fold.
They frequently occur in the same face, one above the other, which is exactly why assessment matters. Treating a hollow with dermal fillers while ignoring the bag above it tends to make the bag more prominent rather than less.
Why the cause decides the treatment
Not every under eye hollow needs correcting, and not every one should be corrected directly. The aesthetic treatments that suit hollow under-eye areas depend entirely on what is producing them.
Where the cause is genuine volume loss, tear trough filler in London, a hyaluronic acid gel placed carefully against bone, restores the transition between lid and cheek. Where the cause is skin quality, skin treatments do more. Where the cause is mid-face descent, treating the cheek can improve the under eye area without anything being placed under the eye at all. And where there is a significant fat bulge, hyaluronic acid filler is usually the wrong answer entirely, and surgical options are the honest conversation to have instead.
As Dr Tapan Patel, founder of PHI Clinic, puts it: non-surgical treatments are generally better suited to milder indications, though occasionally high-impact results are achievable even in severe cases.
That judgement is what a consultation is for. Understanding the cause, the anatomy and the severity comes before any decision about treatment, and risks, expected results and post-treatment instructions are all discussed before anything goes ahead. Sometimes the honest conclusion is that nothing needs doing.
Tear trough assessment in London
Tear troughs and under eye hollows are a normal feature of facial structure and of ageing rather than a fault. Genetics decide where you start, ageing decides how it progresses, and daily factors decide how obvious it looks on any given morning.
Knowing which of those is driving your own under eye appearance is what makes any conversation about cosmetic treatment worth having.
Book a consultation and our practitioners will assess the area properly, explain what is causing it, and tell you honestly whether tear trough treatment at our London clinic is the right answer for you.
