Key ingredients: hyaluronic acid, vitamin B5 | Fragrance-free: yes
Best Budget: Cetaphil 48H Hydrating Serum
Why it’s worth it: Hydration doesn’t have to be expensive—consider Cetaphil’s 48-Hour Hydrating Serum, for example. As this creamy serum turns into a transparent veil on your skin, its combination of hyaluronic acid and sunflower oil attracts and locks in moisture to leave even the driest of skin feeling baby-soft. “It pairs a humectant with an emollient to boost skin’s moisture levels in two different ways,” says Dr. Hartman. Like most of the formulas on this list, Cetaphil’s formula is suitable for all skin types and can be used daily.
Key ingredients: hyaluronic acid, sunflower oil | Fragrance-free: yes
Frequently Asked Questions
How are hydrating and moisturizing ingredients different?
The main difference between hydrating ingredients, known as humectants, and moisturizing ingredients, which fall under the groups of emollients or occlusives, is that hydrators actually pull water from the environment onto the surface layer of the skin, whereas moisturizers prevent water loss. “Humectants attract water molecules, whereas emollients soften the skin by filling in the space between skin cells with the moisturizing ingredient,” says Dr. Hartman. And, according to Dr. Castilla, occlusives mainly reinforce broken patches of the skin barrier, locking in moisture to maintain hydration.
Which ingredients are actually hydrating?
All those oils marketed as “hydrating?” Um, totally untrue, as oils are hydrophobic, meaning they repel water. Instead, look for ingredients labeled as humectants, like hyaluronic acid. This humectant has become the crown jewel of hydrating ingredients simply because it performs well. New York City-based board-certified dermatologist Doris Day, MD, says this particular ingredient is “great at holding water and giving skin resilience and firmness” and is actually produced in our bodies naturally to keep our skin plump and hydrated. Here’s the thing: Our body’s natural supply of hyaluronic acid breaks down as we age, so supplementing this reduction with a topical is a smart move to keep dryness and fine lines at bay.
Like hyaluronic acid, glycerin is another water-attracting humectant that leaves skin with a supple feel. On top of its hydrating benefits, Erin Gilbert, MD, a board-certified dermatologist in New York City says that this ingredient can also help with shedding dead skin for a brighter, clearer complexion. “Glycerin can actually signal your superficial skin cells to mature more rapidly,” she explains.
Meet the experts
- Carmen Castilla, MD, a board-certified dermatologist based in New York City
- Jane Yoo, MD, a board-certified dermatologist based in New York City
- Corey L. Hartman, MD, a board-certified dermatologist based in Birmingham, Alabama
- Kathleen Cook Suozzi, MD, a board-certified dermatologist and associate professor of dermatology at Yale School of Medicine
- Doris Day, MD, a board-certified dermatologist based in New York City
- Erin Gilbert, MD, a board-certified dermatologist in New York City
How we test and review products
When Allure tests a product, our editors look at it from every angle in an effort to best serve you. We review ingredients, scrutinize brand claims, and, when necessary, examine peer-reviewed scientific and medical studies. In addition to testing each and every product that’s included in each and every review, we rely on experts who shape their fields, including dermatology, cosmetic chemistry, and medicine, to help us vet the ingredients and formulas.