If there is one product that has revolutionized modern skincare, it is the serum. But it is also one that creates the most confusion: what exactly does it do? Do I need it if I already use a cream? Does it go on before or after? Can I use more than one?
What is a serum?
A serum is a highly concentrated product designed to penetrate deeper layers of the skin and deliver specific active ingredients efficiently. Its texture is lighter than that of a cream—generally watery or gel-like—which allows it to absorb quickly and act where it is needed most.
The key difference between a serum and a moisturizer is the purpose: the cream hydrates and protects the skin barrier. The serum treats specific concerns: dark spots, wrinkles, lack of radiance, and loss of firmness.
What is each type of serum used for?
- Brightening serum: Most brightening serums have Vitamin C as their main active ingredient. They brighten the skin tone, correct existing dark spots, and provide an antioxidant effect. They work best in the morning.
- Anti-aging serum: Reduces fine lines and improves firmness.
- Hydrating serum: Provides deep hydration, ideal for very dehydrated skin.
- Repairing serum: Restores the skin barrier damaged by the sun, weather, or stress.
At La Forêt, we have serums for different needs: the Absolute Radiance Serum for dark spots, the Aquaplus Repairing Facial Serum for dehydrated skin, the Pearl Elixir reduces visible signs of aging, and the AmbroSea Daily Serum for deep hydration and antioxidant protection.
Does it go before or after the cream?
Before. Always. The serum has a lighter texture and needs direct contact with the skin to penetrate correctly. If you apply the cream first, it creates a barrier that prevents the serum from reaching where it needs to go.
The correct order: cleansing → toner (optional) → serum → moisturizer.
How to combine serum and cream without mistakes?
The rule is simple: the serum treats, the cream seals. The serum deposits the active ingredients into the skin; the cream traps them there while simultaneously hydrating and protecting the barrier.
If your serum is highly active—containing retinol, vitamin C, or acids—make sure your cream is soothing and does not contain the same strong active ingredients. Mixing too many potent actives can irritate the skin.
Can I use more than one serum?
Yes, but use good judgment. If you use two serums, apply the one with the more watery texture first. And avoid combining active ingredients that may react with each other—for example, vitamin C with retinol, or exfoliating acids with retinol.
How much serum should I use?
Less than you think. Two or three drops—or a pea-sized amount—are enough to cover the entire face. Serums are concentrated products; using more does not yield better results.
The serum does not replace the cream, nor does the cream replace the serum. They are complementary products that, together, do much more than each one would do separately.