What is it? According to the American Academy of Dermatology, the main B vitamins present in skincare products are B3 (niacin) and provitamin B5 (pantothenic acid), both helpful in retaining moisture and thus reducing skin irritation. B vitamins are also great exfoliators, helping to clear dull skin and even out skin texture.

In fact, dermatologist Leslie Baumann, M.D., recommends topical niacinamide (a form of B3) as an important ingredient for every skin type. It prevents pigmentation and minimizes dark spots. As a moisturizer, it even helps build the skin's natural barrier, encouraging production of ceramides and fatty acids so skin can keep its own moisture, adds Dr. Baumann.

Those with sensitive skin will find that niacinamide helps keep irritants from harming delicate skin. Sun damage is repaired, and when used with an SPF product, niacinamide provides excellent all-around sun protection. According to Dr. Baumann, you can even use niacinamide safely and effectively while using other ingredients, such as alpha hydroxy acids and retinol.

You'll find it in: Pluck any beauty product off the shelf and chances are that vitamin B plays at least a small role in the list of ingredients. Topical vitamin B and its derivatives are used in anti-aging products to retain moisture and reduce the appearance of fine lines. Niacinamide is used in skin lightening creams to decrease hyperpigmentation. Moisturizers containing niacin and pantothenic acid guarantee that you're hydrating your skin with the most effective ingredients. Many acne treatments use B5 to combat oil and blemishes. According to the British Journal of Dermatology, topical creams with B12 improve eczema and soothe inflammation.

Our product picks: For an effective treatment to make skin appear supple and youthful, try SkinCeuticals Hydrating B5 Gel, which is enriched with vitamin B5 and helps repair tissue for a smooth surface. Oil-free Osmotics Age Prevention Balancing Complex SPF 15, which uses vitamin B6, protects your skin from environmental damage and the sun's harmful ultraviolet rays. Acne sufferers should use Peter Thomas Roth Acne Spot and Area Treatment, a formulation prepared with vitamin B5 to target blemishes and control oil production without dehydrating skin.

What to expect: Although the effects of topical vitamin B aren't as intense or noticeable as other vitamins (such as vitamin A), most people notice significant improvement in the general look of their skin within four to eight weeks. People who are sensitive to other products can safely use vitamin B without worrying about uncomfortable redness or flaking.

Skincare products created with vitamin B help retain high moisture content and produce a glowing skin tone. They also work to clear up unsightly blemishes.

Who should avoid it: Fortunately, skincare products with vitamin B work great for sensitive skin types. Unlike vitamin E, which occasionally triggers irritation, vitamin B offers a gentler alternative to rough exfoliators containing glycolic or salicylic acid. Those suffering from acne, fine lines and dry skin will benefit from vitamin B products without experiencing negative side effects.

Learn everything you need to know about anti-aging skincare in our Anti-Aging Handbook.