If there's one powerhouse ingredient with proven anti-aging abilities, it's retinol. This vitamin-A derivative works to smooth fine lines, remove dead skin cells and encourage collagen production. Don't write off retinol because of its reputation for being irritating; formulations have come a long way, and now, more than ever before, it's a great anti-aging option for just about everyone.

What does retinol do?

"Retinol helps fight the signs of aging by enhancing cell renewal on the skin's surface and causing enhanced collagen production," says Dr. Paul Cohen, a dermatologist at Rosedale Dermatology Centre in Toronto. That means smoother, brighter and more even skin.

Is retinol safe for sensitive skin?

If your skin is sensitive, you might find applying retinol daily, or using it without a skin-calming counterpart, to be irritating. Introduce the ingredient gradually—perhaps once or twice a week to start, then work your way up to everyday use. 

What other ingredients can I use in conjunction with retinol?

"Retinol plays well with hyaluronic acid or glycerin," says Dr. Cohen. In fact, using a hydrating ingredient in tandem with retinol can help reduce irritation brought on by the anti-aging agent. For added skin-renewal benefits, retinol pairs nicely with vitamin C, as well as acids—as long as you take efforts to reduce irritation that can occur when combining two or more strong ingredients.

Is retinol only for anti-aging skin care? 

No! Retinol started out as an acne treatment. But doctors found that it also helped smooth wrinkles, and it was adopted as an anti-aging ingredient. "Retinol is good for anyone with sun damage, uneven skin tone, acne breakouts or acne scarring," says Dr. Cohen.

Does retinol increase sensitivity to the sun?

Retinol stimulates cell turnover and exfoliation, which can make skin more sensitive—both in general and to UV rays. But, according to Dr. Julia Carroll, a dermatologist at Compass Dermatology in Toronto, as long as you wear sunscreen throughout the day, you'll be protected from UV damage. Still worried? Include additional sun protection for your face, such as sunglasses and a wide-brimmed hat. Q: What percentage of retinol should I look for?
"The higher the percentage, the more active the retinol," says Dr. Cohen. But higher doesn't necessarily mean better. If you're new to retinol, test the water with a low concentration (starting at 0.01 percent) and slowly work your way up to a higher percentage (up to one percent) if your skin is able to tolerate one.

Should I use retinol at night or during the day?

You can use retinol day or night; however, most experts recommend using retinol at night, when the skin repairs itself the most.

Which formula is right for me?

"Retinol comes in many forms," says dermatologist Dr. Paul Cohen. "I recommend picking a base suitable for your skin type."

1. If you have oily skin go with a serum.
This lightweight formula absorbs quickly to deliver Retinol SA.

1. Neutrogena® Rapid Wrinkle Repair® Serum, $36.

2. Neutrogena® Rapid Wrinkle Repair® Regenerating Cream, $36. 

3. Neutrogena® Rapid Wrinkle Repair® Moisturizer SPF 30, $36.

Don't discount this favourite drugstore brand when looking for heavy-hitting skin-care ingredients. Neutrogena®'s take on retinol, Retinol SA, offers fast, visible results. "This nourishing formula boosts the efficacy of stabilized pure retinol, making it highly effective yet gentle on the skin—with clinical results," says Dr. Paul Cohen of Rosedale Dermatology Centre in Toronto.

TIP: If your skin is sensitive, avoid applying retinol to your neck, where the skin is more delicate.