what vitamin is lacking to a person with dark circles??

I don't think vitamins would work. I have the exact same problem and my dermatologist told me it's because I have allergies. Do you have allergies too? I have allergies so my dark circles won't be going away unless I do something about my allergies.

Remedies For Dark Circles

* An instant dark circles remedy is to use the correct concealer. The shade should be lighter than your foundation. If circles are very dark, choose 2 shades lighter. Great choices can be Revlon New Complexion Concealer, Estee Lauder Smoothing Skin Concealer, Cover Girl Smoothers Concealer, or Neutrogena Smoothing Skin Stick.

* Apply a good Vitamin K cream. Vita-K Solution gel or Peter Thomas Roth Power K Eye Rescue help strengthen capillary walls around the dark circles to make them less visible.

* One should go for laser treatment only if the case is chronic. Lasers can increase production of collagen thereby thickening skin to make dark circles less visible.

* Home remedies for dark circles can include the following:
1. Drink plenty of water to combat dehydration.
2. Wear at least SPF 30 sunscreen to prevent more sun damage.
3. Get enough sleep.
4. Leave cold teabags, cucumber or potato slices, or washcloths with ice cubes on eyes for 15 minutes regularly.
5. Take iron supplements if anemic, but consult your doctor first.
6. Identify the allergens and avoid them. Whether it be pollen, food, whatever, avoidance is the best solution to this. And avoid rubbing your eyes.

* Hylexin is the first dark circles eye cream developed for serious dark circles. Featured in several magazines such as Marie Claire, FashionWeekDaily, The Wall Street Journal , Star and Luck.

* One of the greatest remedies for dark circles is Arbonne's NutriMinC® RE9 Repair. It’s a corrective puffiness and dark circles eye cream that does additional benefits – firming, moisturizing and repairing the delicate tissue around the eye.

Eat vegetables and fruits that are rich in vitamin E. Include a multivitamin with iron tablet in your diet. Eat at least one green leafy vegetable a day. Check out http://useinfo-darkcircles.blogspot.com/ for more info.

I have dark circles but I think the cause is the same to eyebags... you could be lacking of vitamin K (Green veg) - Although you may eat alot of green veg, sometimes it's the way you cook them - boiling veg will loose out most of the nutritions, choose steaming instead.

Alternatively, you can try putting tea-bags under your eyes in the mornings to "freshen up" your eyes. To do that, you need teabags which have already been "dunked" and put them into the fridge until they are cold and damp. Put them under your eyes for a few minutes.
I never tried this method though, so I'm not sure does it actually work...

Could you be allergic to anything?

Get more sleep and more water

Sometimes it could be due to colour pigment...

Dark circles can be caused by many factors: age, heredity, lack of sleep, rubbing of the eyes, poor nutrition. Vegetables and fruits high in Vitamin have been shown to improve dark circles. Some believe that applying a freshly peeled white potato slice or a slice of cucumber will lighten the circles.

Best advice: Get enough sleep. Be patient, unless they are caused by heredity, the circles will lighten over time as you take better care of your sleep and nutrition.