If Vitamin C is the front and centre skincare ingredient of the year, Vitamin A is the long-shining star, prescribed as an anti-ageing and acne management ingredient for over 50 years.

Both ingredients have skin-boosting benefits, and they can work in synergy together. Vitamin A in skincare helps to stimulate collagen production while Vitamin C helps your skin cells synthesise the new collagen they produce. Both vitamins are antioxidants, which means they can reduce free radical damage and ageing caused by oxidative stress. Vitamin A can also help with oil regulation and acne.

Now for the draw back; Vitamin A can cause sensitivity when you first start using it, and not all forms of Vitamin A are created equally. Here is everything you need to know about the different  types of Vitamin A and how to incorporate it into your skincare routine.

Types of Vitamin A in skincare

The chemical term for all forms of Vitamin A is retinoid, but the most common forms of retinoids you’ll find in skincare are retinol or retinal. They may have different names depending on their molecular structures, but most common forms of Vitamin A can be classified as a retinol or a retinal.

To understand what this all means, it helps to understand how Vitamin A works in the body.

Certain foods (like carrots or orange-fleshed pumpkins) contain beta-carotenes which are converted to Vitamin A in the body. Simply put, when beta-carotene is ingested and converted into retinol, retinol converts into retinal, retinal is converted to make retinoic acid, and retinoic acid is the form that interacts with cell DNA to have an effect on your skin.

When you use skin care products with retinol or retinal, you’re using derivatives of Vitamin A that convert into retinoic acid in your skin. You can sometimes get straight retinoic acid, but it’s normally prescription-only because it can be quite strong.

Which type of Vitamin A should I use?

Both retinol and retinal can help accelerate skin cell regeneration and collagen production to reduce fine lines, ageing and blemishes. Both can also help regulate oil production in the skin. Remember that retinol converts into retinal and retinal converts into retinoic acid to produce these results. Using retinal just means that your skin gets to skip a step.

With any form of Vitamin A, there may be some risk of irritation when introducing it to your skin. This is where Retinaldehyde comes in. According to RejuvAus founder Dr Garry Cussell, retinaldehyde is a newer form of Vitamin A that is more effective but less irritating than other forms of Vitamin A.

Retinaldehyde, however, is difficult to suspend in product formulations, and it must be kept in opaque, air-tight packaging, so very few brands have managed to incorporate retinaldehyde successfully in their products.

How much Vitamin A should I use in my skincare?

When you first start using Vitamin A, you should introduce it slowly to avoid irritation. You can start with a serum that contains 0.5% Retinaldehyde.

To start, apply your Vitamin A serum every other night and gradually move to every night as your skin gets used to it. We recommend night-time use to begin with because it will allow the vitamin to take effect while you sleep. Vitamin A can also increase sensitivity to sunlight, and night-time use will reduce that.

Once applied, the lifespan of Vitamin A in skincare is 8 hours, so you can apply it morning and night once your skin has adjusted to nightly use, but only if you take steps to protect your skin from UV radiation from the sun (which you should be doing anyway).

When you first introduce Vitamin A, your skin may also go through a bit of a purge. There's more on that below.

How do I know if I’m purging or having a reaction?

Vitamin A increases your natural cell turnover, so when you first start using it, your skin may go through a sensitive phase while it purges dead cells and other build up.

You may notice some mild redness and flaking, or even tiny pink pimples. This is normal within the first few weeks with Vitamin A, and it should clear up.

If the redness, light flaking or pimples persist, or if you experience itchiness, stinging or more moderate flaking, stop using your Vitamin A and consult a product specialist or beauty therapist.

Can I use skincare with Vitamin A while I’m pregnant?

Mothersafe, a NSW counselling service for exposures during pregnancy, produced a reliable factsheet on Skincare, Hair Care and Cosmetic Treatments in Pregnancy and Breastfeeding. The factsheet states that doses of Vitamin A taken orally are a matter of concern during pregnancy, but the amounts of Vitamin A that are absorbed into the skin from non-prescription skincare products are usually minimal.

When considering whether a product is safe for pregnancy, the same factsheet advises that you must consider first if the ingredients are safe during pregnancy and second if the ingredient can reach the baby by being absorbed through the skin into the system.

According to Dr Cussell of RejuvAus, retinaldehyde in skincare is safe during pregnancy because it doesn’t enter the bloodstream. If you are uncertain, we recommend speaking to your doctor before proceeding.