Dark Circles Under the Eyes: What Actually Causes Them

Ask most people how to get rid of dark circles under the eyes and you get a pill recommendation. Ask a dermatologist and you get a list: pigment, blood vessels, shadowing, sleep. Only one of those answers is useful, because dark circles are not one condition with one cause. They are a symptom several mechanisms can produce, often in the same person at once [1][3]. So the real question is not which supplement fades dark circles. It is which mechanism is casting the shadow, and whether anything you swallow can reach it.

Why Dark Circles Show Up at All

The classic clinical picture is bilateral, roundish, fairly uniform darker patches just below the eye [1]. Under that skin sit muscle, a small fat pad, a web of fine vessels, and the bone of the eye socket. The covering skin is the thinnest on the face, and thin skin is translucent skin, so what lies underneath shows through more readily than anywhere else.

The recognized contributors read like a list of unrelated problems: melanin in the dermis, post-inflammatory hyperpigmentation, fluid retention, visible superficial vessels, and shadowing from loose or hollowed skin [1]. Reviews keep landing in the same place: dark circles are multifactorial, and one person often has more than one cause at once [3].

Dark circles are a symptom, not a diagnosis. The same shadow can come from pigment, from blood vessels, from hollowing, or from a short night, and each answers to a different lever.

Most cases are not a sign of disease. If you came for the vision side of eye health, our eye health supplements guide covers lutein, bilberry and omega-3s. This article is about the skin beneath the eye.

The Four Mechanisms Behind Dark Circles

Dermatology sorts periorbital hyperpigmentation into four patterns: pigmented, vascular, structural, and mixed [2]. The fourth exists because the first three overlap so often.

Pigmentary: Melanin and Post-Inflammatory Color

Here the darkness is genuine color. Melanin sits in the skin itself, either as normal variation or as pigment left after inflammation, often from eczema or contact dermatitis around the eye [1].

This is where topical research is strongest. A 30-year review of topical therapies for periorbital dyschromia found agents including caffeine, acids, vitamins, glycosaminoglycans and growth factors among those studied [4]. Notice the word topical: an oral supplement does not reach that patch of skin the way a cream does.

Vascular: Pooled Blood and Leaky Capillaries

Vascular circles come from blood pooling in the fine vessels under the eye, or capillaries that leak [1]. Through thin skin, the bluish tone of deoxygenated blood reads as darkness, and it often looks worse in the morning. No trial shows a supplement repairing capillary walls, and where congestion or allergy drives it, the lever is treating the allergy.

Structural: Volume Loss and Thin Skin

Structural circles are about shadow rather than color. Losing fat pad volume, or skin laxity, creates a hollow that throws a shadow [1], and this grows more common with age. A supplement cannot rebuild a lost fat pad, and no trial claims it can. What the collagen and hyaluronic acid trials do support is skin hydration and elasticity, which is skin quality, not the depth of the hollow [10]. Our supplements for skin elasticity guide covers that distinction.

Lifestyle and Systemic: Sleep, Hydration, and Nutrient Status

This is the mechanism where daily habits and internal status show up on the face. Sleep loss measurably changes how the under-eye area looks [7], and it is the one mechanism where an oral supplement has a real, if limited, role.

Most people are not one mechanism. They are two or three, which is why a single product rarely matches what they see.

Sleep: The Best-Evidenced Lever You Already Have

If one item here has strong human evidence behind it, it is sleep. When 40 observers rated photographs of 10 people after normal sleep and after 31 hours of deprivation, the sleep-deprived faces were judged to have darker circles under the eyes and paler skin, plus hanging eyelids and more swollen eyes [7]. In another study, 24 women restricted to three hours of sleep a night for two nights showed lower skin hydration, higher water loss, and reduced extensibility and viscosity, all statistically significant [8]. A third found sleep deprivation increased facial skin yellowness [9].

That is not a supplement claim. It is a statement that sleep changes the skin you are looking at. Our sleep supplements guide is about matching a product to a specific sleep problem, not replacing sleep itself.

Collagen and Hyaluronic Acid: What the Trials Actually Measured

These two are the most marketed for under-eye appearance and the most misrepresented, so the honest reading matters most here.

What the Collagen Trials Actually Measured

Oral collagen has genuinely good evidence, for a specific outcome. A meta-analysis of 19 randomized controlled trials in 1,125 people aged 20 to 70 found a favorable effect on skin hydration, elasticity and wrinkles versus placebo [10]. A later meta-analysis of 26 trials in 1,721 people reported significant improvements in hydration and elasticity, while noting bias in the included studies [11]. A double-blind trial of 69 women taking 2.5 g or 5.0 g of collagen hydrolysate daily found skin elasticity improved significantly versus placebo, though moisture did not reach significance [12].

Now the part that never makes the label. None of those trials measured dark circles. They measured hydration, elasticity and wrinkle depth, which are real skin outcomes but not the shadow under your eye.

The Hyaluronic Acid Picture

A meta-analysis of seven randomized trials of oral hyaluronic acid found significant improvements in skin hydration, elasticity and wrinkle depth, while firmness, wrinkle volume and water loss were not significant [13]. A 12-week trial in 60 women found improvements in wrinkles, smoothness and roughness [14]. Again the endpoint is skin quality, not the appearance of dark circles, and our collagen dosage guide covers how much to take and which type.

Oral collagen and hyaluronic acid have solid evidence for skin hydration and elasticity. They have essentially no evidence for fading dark circles, because none of the trials reviewed here measured that outcome.

Vitamin C for Skin: What It Does and Does Not Do

Vitamin C has two jobs here, and they should stay apart.

The first is collagen synthesis. Skin holds high concentrations of vitamin C, and it supports collagen synthesis and the stabilization of collagen fibers [15][16], so it is a genuine nutritional input to skin structure.

The second is pigmentation. Topical vitamin C has been shown to decrease melanin formation, thereby reducing pigmentation [16]. That is a topical finding, and the oral evidence for the same effect under the eye is far weaker. A well-formulated topical is the better-evidenced route if pigment is your mechanism.

Allergies and Allergic Shiners

Allergy is a real and under-discussed cause. Allergic shiners, meaning dark circles under the eyes, are a common examination finding in allergic rhinitis [17], one of the most common chronic conditions in the United States. The driver is vascular and congestive: chronic nasal swelling impairs drainage of blood from around the eye, so it pools and shows through thin skin.

The implication is uncomfortable for a supplement brand and worth saying anyway. If allergy is driving your dark circles, the lever is treating the allergy, usually a conversation with a clinician or pharmacist about antihistamines or nasal treatment. Our natural allergy relief guide covers the non-drug options that do have evidence.

Nutrient Status Worth Testing, Not Guessing

Some causes are worth investigating rather than supplementing blindly, and that investigation starts with a clinician and a blood test.

B12 and Pigmentation

B12 deficiency is a recognized cause of skin hyperpigmentation, and recent case reporting calls it an under-recognized clue, with treatment reversing it [18]. A series of 57 infants with B12 deficiency found hyperpigmentation in the large majority, improving after treatment in most [19]. That is a pediatric population, so it shows the link exists without predicting what an adult would see.

Iron and Pallor

Iron deficiency anemia changes how skin looks, and pallor is the classic sign. In 110 children under two with the condition compared with 100 children who had a different anemia, pallor was observed in all of the children with iron deficiency anemia [20]. Again pediatric, cited only to show that the sign is real and detectable.

This is where this article refuses to hand you a product. Iron is a test-then-prescribe nutrient. Taking it because you look tired, without knowing your status, is the wrong order of operations, and excess iron carries its own risks. The same goes for B12 and thyroid function. If your circles came on suddenly, affect one side, or arrive with fatigue or unusual paleness, ask your clinician to check these. Our iron supplements guide explains the forms and timing once a clinician has told you to supplement.

The Honest Limits of the Evidence

Here is the gap this article exists to name. Research on treatments that specifically fade dark circles is thin. A systematic review of 39 studies of periorbital hyperpigmentation treatments concluded that given the scarcity of high-quality evidence supporting these results, recommendations should be interpreted selectively [5]. The authors are warning you to be cautious about their own findings.

The supplement side is no stronger. A narrative review of oral supplementation for skin aging found that oral hydrolyzed collagen and hyaluronic acid are well tolerated and can mitigate some signs of skin aging, but concluded that the evidence is lacking on the effects of the many dietary supplements on offer, such as vitamins, flavonoids, plant extracts and trace elements [6].

• Well evidenced: collagen and hyaluronic acid for hydration and elasticity, and sleep for under-eye appearance.
• Reasonably evidenced, topically: vitamin C and other actives for pigmentation.
• Poorly evidenced: any oral supplement fading dark circles.
• Not a supplement question: allergy, iron, B12 and thyroid.

The FDA does not review dietary supplements for effectiveness before they are sold, so that gap is left to you and your clinician to navigate [21].

What Actually Helps Today

If you want something to act on now, the most defensible steps are the unglamorous ones.

1. Protect the area from sun. Daily sun protection is standard advice for pigmentary skin concerns and costs nothing to start.
2. Treat sleep as the intervention. Consistent, adequate sleep has the strongest human evidence in this article [7][8].
3. Keep skin hydrated. Both the collagen and hyaluronic acid studies point at hydration as an improvable skin outcome [10][13].
4. Do not smoke. Smoking constricts blood vessels and degrades collagen and elastin over time.
5. Handle allergy as allergy. If congestion and itching come with your circles, address that with a clinician [17].
6. Be patient. Changes in hydration and elasticity in these trials were measured at 8 to 12 weeks, not overnight [12][14].

Agape Nutrition has carried professional-grade supplements since 1998, and our skin and cosmetic care hub is where the skin-structure products sit if you decide that route fits your mechanism.

When to See a Clinician

Most dark circles are cosmetic and harmless. A smaller set deserve a look. Book an appointment if any of these apply:

• One-sided or sudden darkening, rather than a gradual change on both sides.
• Pain, tenderness, swelling or a lump around the eye.
• A change in vision, or a persistent red or irritated eye.
• Circles with fatigue, breathlessness, unusual paleness or unexplained weight change, which warrant a check of iron, B12 and thyroid status [18][20].
• Darkening that keeps spreading beyond the eye area.

None of these are reasons to panic. They are reasons to have a clinician look, because the cause may be something a supplement cannot touch and should not be expected to.

What We Recommend

The mechanisms a supplement can genuinely reach are the skin structure ones, so these picks stay inside the categories this article found evidence for: collagen, hyaluronic acid, vitamin C, and a topical. They support skin hydration, elasticity and topical skin care, not the shadow itself.

References

1. Freitag FM, Cestari TF. What causes dark circles under the eyes? Journal of Cosmetic Dermatology. 2007;6(3):211-5. https://pubmed.ncbi.nlm.nih.gov/17760701/

1. Samaan CB, Cartee TV. Treatment of Periorbital Vascularity, Erythema, and Hyperpigmentation. Clinics in Plastic Surgery. 2023;50(3):399-409. https://pubmed.ncbi.nlm.nih.gov/37169406/

1. Friedmann DP, Goldman MP. Dark circles: etiology and management options. Clinics in Plastic Surgery. 2015;42(1):33-50. https://pubmed.ncbi.nlm.nih.gov/25440739/

1. Woolhiser E, Sobotka M, Burnette C, et al. Topical Therapies for Periorbital Dyschromia: A 30-Year Review of the Literature. Dermatologic Surgery. 2025;51(2):157-160. https://pubmed.ncbi.nlm.nih.gov/39412152/

1. Michelle L, Pouldar Foulad D, Ekelem C, et al. Treatments of Periorbital Hyperpigmentation: A Systematic Review. Dermatologic Surgery. 2021;47(1):70-74. https://pubmed.ncbi.nlm.nih.gov/32740208/

1. Morgado-Carrasco D, Gil-Lianes J, Jourdain E, et al. Oral Supplementation and Systemic Drugs for Skin Aging: A Narrative Review. Actas Dermo-Sifiliograficas. 2023;114(2):114-124. https://pubmed.ncbi.nlm.nih.gov/36206809/

1. Sundelin T, Lekander M, Kecklund G, et al. Cues of fatigue: effects of sleep deprivation on facial appearance. Sleep. 2013;36(9):1355-60. https://pubmed.ncbi.nlm.nih.gov/23997369/

1. Leger D, Gauriau C, Etzi C, et al. "You look sleepy..." The impact of sleep restriction on skin parameters and facial appearance of 24 women. Sleep Medicine. 2022;89:97-103. https://pubmed.ncbi.nlm.nih.gov/34971928/

1. Matsubara A, Deng G, Gong L, et al. Sleep Deprivation Increases Facial Skin Yellowness. Journal of Clinical Medicine. 2023;12(2). https://pubmed.ncbi.nlm.nih.gov/36675544/

1. de Miranda RB, Weimer P, Rossi RC. Effects of hydrolyzed collagen supplementation on skin aging: a systematic review and meta-analysis. International Journal of Dermatology. 2021;60(12):1449-1461. https://pubmed.ncbi.nlm.nih.gov/33742704/

1. Pu SY, Huang YL, Pu CM, et al. Effects of Oral Collagen for Skin Anti-Aging: A Systematic Review and Meta-Analysis. Nutrients. 2023;15(9). https://pubmed.ncbi.nlm.nih.gov/37432180/

1. Proksch E, Segger D, Degwert J, et al. Oral supplementation of specific collagen peptides has beneficial effects on human skin physiology: a double-blind, placebo-controlled study. Skin Pharmacology and Physiology. 2014;27(1):47-55. https://pubmed.ncbi.nlm.nih.gov/23949208/

1. Amin P, Sarabi A, Choe S, et al. Oral Hyaluronic Acid Supplement: Efficacy in Skin Hydration, Elasticity, and Wrinkle Depth Reduction. Journal of Drugs in Dermatology. 2025;24(9):910-919. https://pubmed.ncbi.nlm.nih.gov/40911749/

1. Montero-Vilchez T, Galvez-Martin P, Sanabria-de la Torre R, et al. Oral Supplementation with a New Hyaluronic Acid Matrix Ingredient Improves Skin Brightness, Hydration, Smoothness, and Roughness: Results from a Randomized, Double-Blinded, Placebo-Controlled Study. Dermatology and Therapy. 2025;15(8):2099-2116. https://pubmed.ncbi.nlm.nih.gov/40498387/

1. Pullar JM, Carr AC, Vissers MCM. The Roles of Vitamin C in Skin Health. Nutrients. 2017;9(8). https://pubmed.ncbi.nlm.nih.gov/28805671/

1. Al-Niaimi F, Chiang NYZ. Topical Vitamin C and the Skin: Mechanisms of Action and Clinical Applications. Journal of Clinical and Aesthetic Dermatology. 2017;10(7):14-17. https://pubmed.ncbi.nlm.nih.gov/29104718/

1. Weaver-Agostoni J, Kosak Z, Bartlett S. Allergic Rhinitis: Rapid Evidence Review. American Family Physician. 2023;107(5):466-473. https://pubmed.ncbi.nlm.nih.gov/37192071/

1. Mathur M, Paudel S, Karki S, et al. Skin Hyperpigmentation: An Under-Recognized Dermatological Clue to Vitamin B12 Deficiency. Clinical Case Reports. 2026;14(5):e72634. https://pubmed.ncbi.nlm.nih.gov/42052311/

1. Demir N, Dogan M, Koc A, et al. Dermatological findings of vitamin B12 deficiency and resolving time of these symptoms. Cutaneous and Ocular Toxicology. 2014;33(1):70-3. https://pubmed.ncbi.nlm.nih.gov/24303868/

1. Abdel Rasool A, Hameed AH, Alkhalidy L. Clinical and Nutritional Assessment of Iron Deficiency Anemia in Children Under Two Years of Age. Medical Glasnik. 2025;22(2):283-287. https://pubmed.ncbi.nlm.nih.gov/41082754/

1. U.S. Food and Drug Administration. Dietary Supplements. https://www.fda.gov/food/dietary-supplements

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