Vitamin A (retinoid)
What it does: Fades brown spots and smooths roughness.Where to find it: Lotion, treatment creams and night creams (vitamin A derivatives are known as retinoids), and prescription products.
How to use it: Apply retinoids only at night, since sunlight inactivates most forms of vitamin A. Prescription retinoids work fastest, within four to eight weeks.
Note: Some retinoids can cause redness, scaling, and flaking. If you’re new to retinoid use, start by applying every second or third night for the first two weeks, and build up to nightly use. Apply sparingly; a pea-size amount is enough to cover your entire face.
Vitamin B3 (niamcinamide)
What it does: Helps increase skin hydration, makes skin less irritable and reduces dark spots.
Where to find it: Lotions, creams and serums.
How to use it: For maximum results, apply B3 vitamins twice a day. To reduce irritation from your retinoid, use it in conjunction with niacinamide by mixing them together in the palm of your hand before applying.
What it does: Helps smooth the skin and fades dark spots. It also destroys the free radicals that trigger sagging and other aging changes.
Where to find it: Serums and moisturizers. Look for C near the middle of the ingredients panel to help ensure the 5% or higher concentration.
How to use it: Apply vitamin C in the morning before applying sunscreen.
What it does: Prevents dryness by helping skin retain its natural moisture, neutralizes damaging free radicals, and boosts the skins’s UV defenses.
Where to find it: Serums, moisturizers and sunscreens and after-sun products. The best anti-aging products contain at least 1% vitamin E.
How to use it: Follow the instructions for the particular product you’re using, and be sure to apply before sun exposure.
What it does: Reduces dark circles under eyes
Where to find it: Eye creams.
How to use it: Apply at night.
Source : http://blackdoctor.org