Everything You Need To Know About Hyaluronic Acid

Want plumper, softer and more hydrated skin? Right this way.

September 1, 2021

A model with luminous skin against a blue background to illustrate an article about hyaluronic acid skincare.

(Photo: iStock)

If you've bought a moisturizer or a serum recently, you may have seen the words hyaluronic acid on the front of the box. But what exactly is hyaluronic acid—and why should you be using it? While it's a hot ingredient in skincare, hyaluronic acid (or HA as it's often called) is also produced by our bodies to retain water, which helps plump and hydrate the skin. When applied topically, it has the same effect—a more hydrated complexion.

With dry indoor air season just around the corner (thanks, heating!), now is a good a time to learn about one of the most hydrating ingredients in the beauty biz. Read on for expert tips on how to use hyaluronic acid skincare from Dr. Sonya Abdulla, medical and cosmetic dermatologist at Dermatology on Bloor in Toronto, and Ellis Holevas, Senior Clinical Educator and Brand Ambassador for AlumierMD.

What is hyaluronic acid and what does it do for the skin?

"Hyaluronic acid is [naturally] produced in the dermal layer of the skin," says Holevas. It gives your skin structure and acts as a magnet for moisture, drawing water into the skin to boost hydration levels. It holds up to 1,000 times its weight in water and has anti-aging benefits, leaving skin plumper, softer and smoother, adds the expert. Unfortunately, according to Abdulla, we lose approximately 1 percent of our hyaluronic acid stores per year after the age of 30 (or 10 percent per decade). In addition, older skin also produces less HA, which leads to crepe-y texture, visible fine lines and volume loss. Thankfully, by adding hyaluronic acid to your beauty routine, you can give your skin a boost of radiance and plumpness.

Are there different types of hyaluronic acid?

The types of hyaluronic acid used in skincare differ depending on their size. "In skincare, the molecular weight of the hyaluronic acid molecule will dictate the depth where it is found in [your]," explains Abdulla. High molecular weight hyaluronic acid sits on top of the skin (due to its large size) and hydrates, while a low molecular weight is small enough to penetrate into the dermis to help replenish the HA loss that occurs during the aging process, says Holevas. In addition to re-upping HA levels in the skin, low molecular weight HA also supports collagen production and firms the skin. Holevas says that in skincare, a combination of both forms is best as you can benefit from their different properties. When shopping, look closely at product packaging as brands often indicate on the box if a formula contains HA with a low or high molecular weight (or both).

When should I use hyaluronic acid?

While some skincare ingredients, like retinol, are best used at night and others, like vitamin C, work their magic in the daytime, hyaluronic acid can be used both morning and night. "I recommend use of an HA serum up to twice daily, depending on your skin's needs," says Abdulla. "Masks can be used intermittently when you have time to squeeze it in as a boosting treatment, typically before bed." Holevas adds that you can use HA everyday in your skincare routine as it's gentle on the skin.

How do I apply hyaluronic acid?

"The skin can be freshly cleansed, lightly pat dry and then apply your HA product to your skin," says Holevas. "It's best applied on damp skin, as the hyaluronic acid will then bind the moisture and will hydrate through the layers of your skin."

Can I mix hyaluronic acid with other skincare ingredients?

Yes! While it has acid in the name, it differs from exfoliating acids like glycolic or lactic acid. HA is gentler on the skin as it's naturally produced by your body and it pairs well with other ingredients, including other actives like retinol. "[It] tolerated by any skin type—sensitive, oily or combination skin—and allows for easy integration into a skincare routine," says Abdulla. You can layer hyaluronic acid with retinol or glycolic acid, but be sure to let the products sink into your skin after each step. By using a hyaluronic acid serum or moisturizer on your skin first and layering a retinol (or other active) over top, the HA can help prevent some irritation that may occur from the retinol.

How do I pick the right hyaluronic acid skincare for me?

HA is readily abundant in beauty aisles in a plethora of skincare products from face washes and masks to moisturizers, but Abdulla recommends reaching for a serum if possible. "Serums continue to be the most effective way to deliver active ingredients to the skin," she says. "For hyaluronic acid, water-based serums allow it to optimize its effects." When applied correctly, HA serums will leave your skin feeling plump and smooth.

With some actives, looking for a percentage of the ingredient in the product is key but with hyaluronic acid, a set percentage is not essential as it varies depending on the type of HA used in the product. If it's in a pure form, Abdulla says the percentage will be around 1 percent in a serum—anything more than 1 percent may have the opposite effect on your skin, acting as a sponge to draw moisture away rather than replenish it.

Is there a difference between more expensive HA skincare and a cheaper option?

Is it worth splurging on a more expensive product or will a cheaper drugstore dupe do? Since hyaluronic acid isn't known to irritate the skin (like, say, retinol), a cheaper product will most likely work just as well, depending on your preference and your skin's needs. When it comes to skincare, the quality and source of the hyaluronic acid is relevant, as well as the additional molecules added to the product, says Abdulla. "Medical grade products tend to be more of an investment for this reason as these products are backed by science including clinical trials showing their efficacy."