:by Kate Dee, MD
Vitamin C is one of the best-studied of the anti-aging ingredients. It is a powerful antioxidant with many benefits:
lightens the skin and reduces the appearance of brown spots
increases collagen production, diminishing fine lines and wrinkles
reduces redness and inflammation
boosts skin's natural healing and repair, decreasing post-inflammatory red marks
protects against the ravages of the sun
The most common and best-studied form of Vitamin C is ascorbic acid, but there are many other chemical forms. Vitamin C serums often contain a combination of 3 or 4 forms or may be combined with other anti-oxidants and retinol. Vitamin C is notoriously unstable, so look for packaging that is air-tight and opaque. Even with the best packaging, once opened, it tends to break down over time, so buy it in small amounts. There is no point in using it sparingly and trying to make the vial last-- over time, it will break down and become useless!
The best time to incorporate Vitamin C into your daily routine is in the morning before using a daily moisturizer with sunblock (but it can be used in the evening as well). If used regularly, it can help maintain younger firmer skin while minimizing sun spots and acne scarring.