Mar 20, 2025
Dark Under-Eyes: What Causes Them and How to Fix Them
Tired of looking tired? Your dark under-eye circles could be trying to tell you something. Here’s how to get to the root cause—and start fading them naturally.
Written by
Mito Team
Dark under-eye circles are one of the most common cosmetic concerns faced by people of all ages. Whether they’re caused by fatigue, stress, or genetics, under-eye circles leave you looking tired even when you’re feeling fine. Understanding the root causes of these pesky shadows—and the best ways to treat them—will help you brighten your complexion and regain confidence.
What’s Behind Dark Under-Eye Circles?
There’s no single reason dark circles appear. In most cases, it’s a mix of things going on in your body and lifestyle.
1. Not Enough Sleep
Poor sleep quality is one of the biggest causes of dark eye circles. When you're not well-rested, your skin looks paler, which makes the blood vessels under your eyes stand out more. Lack of sleep also causes puffiness, creating shadows that look like dark circles.
2. Dehydration
When you’re not drinking enough water, your skin becomes dry and dull, especially around the eyes, where the skin is thinnest. This makes your under-eye area look sunken and darker than usual.
3. Low on Key Nutrients
If your body is low in iron, vitamin D, or B12, dark circles become more noticeable. Iron helps your blood carry oxygen. Without enough of it, your skin looks pale, which makes the darkness under the eyes stand out. Vitamins C, K, and the B-complex group also support skin health and circulation.
To check your levels of important nutrients, take a ferritin blood test. This test measures how much stored iron you have in your body.
4. Stress
Ever heard of “adrenal fatigue”? While it's not a recognized medical condition, it often describes what people feel during long-term stress. You’re tired, wired, and just not quite right.
Chronic stress messes with your sleep, hydration, and even how well your kidneys and liver work. All of which may lead to darker under eyes. If you want to understand how stress affects your body and deal with its symptoms, it's a good idea to get your cortisol levels checked.
5. Allergies or Sinus Issues
If you deal with seasonal allergies, you might notice something called “allergic shiners.” These dark circles are caused by swollen blood vessels under the eyes from sinus congestion. Rubbing your eyes makes it worse by irritating the delicate skin or even breaking small capillaries.
To get a clearer picture of how serious your allergies are, it might be a good idea to get a blood test to check your eosinophil levels.
6. Insulin Resistance
Some studies suggest a link between insulin resistance and dark circles, especially in younger people. High insulin levels may cause changes in pigmentation or make blood vessels more visible.
It might be a good idea to check your fasting blood glucose, triglycerides, and high-density lipoprotein cholesterol levels. These help you understand your insulin levels and overall health, and they might be linked to those dark circles under your eyes.
7. It’s in Your Genes
Sometimes, it just runs in the family. If your parents have dark circles, you might have inherited the same skin structure or pigmentation. That doesn’t mean there’s nothing you can do, but it may take more consistency and care to see results.
8. It’s a Sign of Something More
In rare cases, dark circles are a clue that something deeper is going on, like thyroid issues, kidney concerns, or liver problems. If your dark circles are sudden or worsening, it’s worth checking in with a healthcare provider.
How to Reduce Dark Circles Under Your Eyes
Now that you know the causes, let’s talk about what you can do. There isn't a single fix that works for everyone, but using a mix of different methods usually gives the best results!
1. Get Better Sleep
Try to sleep 7 to 9 hours each night. Go to bed and wake up at the same time every day—even on weekends. A calm bedtime routine, like reading or taking a warm shower, helps your body relax.
2. Drink More Water
Well-hydrated skin is healthier and plumper. This helps reduce the shadowy effect caused by blood vessels under the eyes.
3. Supplement Smartly
If a blood test reveals deficiencies, supplements may help reduce dark circles under the eyes. Common supplements include:
Iron helps improve circulation if you're anemic
Vitamin C boosts collagen and brightens skin
Vitamin D supplements support overall skin health
B-complex vitamins, especially B12 and B3, supports energy and skin tone
Melatonin improves sleep
Always consult with a healthcare provider before starting new supplements.
4. Cut Back on Problem Foods
Some people notice a difference when they eat less dairy, gluten, sugar, or alcohol. These causes inflammation or dehydration, making dark circles worse. You might want to try cutting them out for a week or two and see how your skin responds.
5. Move Your Body
Cardio exercises like walking, running, or biking help boost blood flow and reduce puffiness under your eyes. Just make sure to drink water after your workout to avoid dehydration.
6. Try Gua Sha or Gentle Facial Massage
This is a simple tool to lightly massage the skin around your eyes. It helps move fluid out of the area and improves circulation, which may make dark circles less noticeable. Be super gentle, though, because the skin under your eyes is delicate.
7. Treat Your Allergies
If allergies are contributing to your dark circles, antihistamines, nasal sprays, and allergy eye drops provide relief. When your sinuses are clear, the veins under your eyes don’t get as swollen and noticeable.
8. Use Eye Creams That Work
Many under-eye circle treatments come in the form of eye creams formulated with:
Vitamin C to brighten skin
Retinol to boost collagen
Caffeine to reduce puffiness
Vitamin K helps with blood flow
Niacinamide (B3) to reduce discoloration
Hyaluronic acid to hydrate and plump
Consistency is key. So apply your eye cream gently every morning and night for the best results.
Final Thoughts
Dark under-eye circles can be frustrating, but they’re often a sign that something in your lifestyle or health could use some attention. Whether it’s sleep, hydration, diet, or even allergies, small changes add up to big improvements. And remember, everyone's skin is different. What works for someone else might not be what works best for you.
At Mito Health, we believe in getting to the root cause, not just covering up the problem. If dark circles are something you’re dealing with, take it as a cue from your body. Our comprehensive blood panel looks at over 100 biomarkers to figure out hidden reasons why you might be stressed, have chronic allergies, or lack key nutrients, which all lead to dark under eyes.