Intelligent Retinol 10TR

Retinol at 1% in an anhydrous squalane and safflower base. The top of the Intelligent Retinol ladder.

Retinol at 1% in an oil base — squalane, safflower seed oil and caprylic/capric triglyceride — with vitamin E and BHT holding the retinol stable. There is no water in the formula.

One per cent is the top of this ladder and not the entry to it. Retinol takes two conversion steps to reach retinoic acid, the form skin responds to, which is why it is used at higher percentages than retinal. The numbers on the two ranges do not map onto each other.

Four drops in the evening. Twice a week for the first fortnight, every other night for the next, then nightly. Sunscreen every morning while you are using it.

Made for skin already established on Vitamin A.

Actives: Retinol 1%

Suits: Skin already established on Vitamin A and settled at a lower rung.

Not for: Skin new to Vitamin A, or currently reactive. Not for use during pregnancy or breastfeeding.