Main content
What Does it Mean if My Antioxidant Serum is Gold or Amber in Color?

What Does it Mean if My Antioxidant Serum is Gold or Amber in Color?

Does the color of your vitamin C serum matter? Dr. Jenny Liu, MD, FAAD and a Research & Innovation specialist from the SkinCeuticals lab explain why it’s less important to focus on the color and more important to focus on the ingredients and clinical proof.


Article Overview

  • Dr. Jenny Liu, MD, FAAD and a Research & Innovation specialist from the SkinCeuticals lab discuss how to determine if a vitamin C serum has oxidized and how oxidation is not an indicator of product effectiveness.
  • The color of a vitamin C serum can range from clear to light yellow or light brown. Even after a vitamin C serum color has changed, the product is still effective, and the active ingredients remain potent.
  • There are different factors that contribute to serum oxidation such as exposure to air, light, and heat.
  • To reduce the chance of your vitamin C serum changing color, you can follow tips such as storing your serum in a cool, dark place, closing your bottle tightly after each use, and finishing your bottle within 3 months of opening for optimal potency.

It’s a fact that the color of a vitamin C serum can vary from bottle to bottle. However, it’s important to know that SkinCeuticals vitamin C serums—including C E Ferulic®, Phloretin CF, and Silymarin CF—are effective even if the color changes.

Here, board-certified dermatologist and Assistant Professor of Dermatology at the University of Minnesota Medical School Dr. Jenny Liu and SkinCeuticals Research & Innovation specialist Maggie Su talk about what color changes mean, and why they don’t impact the results that your SkinCeuticals vitamin C serum is formulated to deliver.

DR. LIU: Vitamin C is an indispensable ally in the quest for healthy, resilient skin; acclaimed for its antioxidant properties that guard against oxidative stress, and its crucial role in promoting natural collagen synthesis for anti-aging benefits. Pure vitamin C, while a potent antioxidant, is known for its instability when exposed to light, air, and heat, leading to rapid oxidation. This characteristic makes the formulation of vitamin C serums a precise science.

SU: SkinCeuticals sets the industry benchmark by delivering stabilized serums that harness the full power of vitamin C and remain effective despite the ingredient's naturally reactive nature. Taking a meticulous approach when incorporating pure L-ascorbic acid (Vitamin C) with other antioxidants is part of our commitment to quality without compromising efficacy.

DR. LIU: With over 20 years of research underpinning your work, SkinCeuticals' approach to vitamin C serums is firmly rooted in scientific evidence. The brand’s unwavering focus on stability and skin bioavailability has established it as a standard-bearer in the field. However, some of my fellow doctors and patients have observed color variations in the serums. What color should a vitamin C serum be when you first open the bottle?

SU: The color of a vitamin C serum can range from clear to light yellow or light brown when you break the seal that was placed on the bottle immediately after it was filled in our manufacturing facility.

DR. LIU: But is the product still effective when I open it if the color is darker?

SU: The serum itself has been specially formulated to preserve the integrity of the vitamin C, and color is not an indicator of product effectiveness. We have also performed quality standards testing that simulates real word conditions to show the active ingredients remain potent even if the color has shifted.

DR. LIU: It’s good to know that SkinCeuticals testing has verified that the therapeutic efficacy of the serums remains unaltered, irrespective of the natural color transformation over time. As a result, SkinCeuticals vitamin C serums reliably provide continuous antioxidant protection and contribute to anti-aging skincare regimens.

DR. LIU: Why does the formula turn gold or amber?

SU: Our antioxidant serums are formulated with a very high level of pure vitamin C (L-ascorbic acid) for maximum antioxidant protection, as opposed to a vitamin C derivative. Due to its chemical composition and how it naturally reacts with external elements like air and light, it’s normal for a pure vitamin C serum to shift to a gold or amber color after you open the bottle and continue to use it daily, or even shortly after it is produced.

DR. LIU: Is it normal for the serum to darken after the bottle has been opened?

SU: After opening, the formula may continue to shift color with daily use due to exposure to light and air—but it remains effective. SkinCeuticals has also performed lab tests that simulate daily use for six months, including opening and closing the bottle every day. This testing showed that the formula remains effective until the last drop.

DR. LIU: I keep my vitamin C serum in a cool, dark place to protect it from light, heat, and humidity. Do you have any other tips for reducing the chance a vitamin C serum will change color?

SU: There are few other simple ways to help maintain a vitamin C serum’s color.

  • Keep vitamin C away from sunlight and heat since pure vitamin C is highly sensitive to UV rays and heat. Keep in a cool, dark place.
  • Close your vitamin C bottle tightly after every use since air exposure can cause pure vitamin C to change color as well.
  • Make a note of the date you first open your bottle of vitamin C serum. Although SkinCeuticals testing shows effectiveness for six months with normal daily use, we recommend finishing a bottle within three months for optimal potency and results.
  • An unopened vitamin C antioxidant retains its effectiveness for up to three years when stored away from direct sunlight.

DR. LIU: SkinCeuticals vitamin C serums, with their scientifically-backed formulations and consistent quality control, stand resilient against the natural process of oxidation. Users can trust in the unwavering benefits of these serums, assured by the brand’s commitment to delivering a product that remains effective through every use.

To learn more about SkinCeuticals antioxidants or find the ideal formula for your skin type and skin concerns, use our online Routine Finder, visit one of our SkinCeuticals SkinLab locations, or schedule an appointment with a SkinCeuticals Skincare Professional for a one-on-one consultation.


Shop Featured Products



Orientation message
For the best experience, please turn your device