Retinol is among the antiaging superstar ingredients you should be looking for when shopping for skin care to help you look younger. In order to make the Best Products list, a product with retinol must:

• Contain an efficacious amount of retinol
• Be packaged to ensure the retinol will remain potent and stable during use (clear or jar packaging is out)
• Contain other antiaging ingredients such as proven antioxidants and skin-repairing ingredients
• Contain minimal to no fragrance and no needless irritants

All of the retinol products on this list are packaged to ensure that the retinol remains stable during use, which is absolutely essential for this light- and air-sensitive ingredient. Each also contains an amount of retinol that is within the range of what research has shown to be effective.

Whether you choose a moisturizer or serum with retinol comes down to preference and skin type. Generally, someone with dry skin is likely to prefer a moisturizer with retinol while someone with oily skin will prefer a serum with retinol, but experiment to see which texture works best with the other products in your skin-care routine.

You can apply a retinol product once or twice daily (first-time users should apply once every other day, preferably in the evening). Generally, it is best to apply a retinol product at night. If you opt to use one during daylight hours, you must protect your skin with a well formulated sunscreen rated SPF 15 or greater.

It is fine to combine any retinol product with an AHA or BHA product. However, because retinol can cause mild flakiness and sensitivity for some people, pay attention to how your skin responds. If you notice undesirable side effects, decrease frequency of use or separate application so you use the retinol product in the evening and exfoliant as part of your daytime routine.

It is also OK to combine a retinol product with a prescription retinoid such as  Renova or other forms of tretinoin. Keep in mind that doubling up may increase your risk of side effects such as redness, sensitivity, and flaking. Should this occur, stop using the over-the-counter retinol product and see how your skin reponds just to the prescription retinoid.

Lastly, keep in mind that with retinol, more is not better. It doesn't take much retinol to prompt positive changes in your skin, but higher amounts (generally approaching 1% or greater) can tip the scales in favor of irritation, which is never the goal. Repeat after us: more retinol is not better and may make matters worse!