Vitamin C is an important skin care ingredient, but if used incorrectly, the skin can age unexpectedly quickly.
Vitamin C - a 'double-edged sword' in the skin care journey if you use it incorrectly
Vitamin C brings many benefits to the skin such as brightening the skin, reducing dark spots, and anti-aging.
Vitamin C has long been considered a "miracle drug" in the skin care process thanks to its ability to brighten the skin, reduce dark spots, and increase collagen production. However, when used incorrectly, this ingredient can make the skin dull, dark, and even accelerate the aging process.
Dermatologist Audrey Kunin, a member of the American Academy of Dermatology, warns: "Vitamin C is very sensitive to light, temperature, and air. If stored or used incorrectly, the effectiveness of the product will decrease, and it will also produce free radicals that are harmful to the skin."
- Using oxidized vitamin C
One of the most common mistakes is using oxidized vitamin C. When the serum turns dark yellow, brown, or has a strange smell, it is a sign of oxidation. Although many people regretfully continue to use it, in fact, the product has lost its effectiveness and can even create dehydroascorbic acid, an unstable form that can irritate and darken the skin.
Research published in the Journal of Cosmetic Dermatology (2021) confirmed that broken-down vitamin C can contribute to oxidative stress on the skin, a leading cause of premature aging.
- Not using sunscreen
Many people also make the mistake of applying vitamin C during the day without using sunscreen. Although the nature of vitamin C can fight the harmful effects of UV rays by neutralizing free radicals, if the skin is not properly protected, this product itself makes the skin more susceptible to sunburn. Vitamin C in the form of L-ascorbic acid can make the skin sensitive to sunlight, leading to darkening and deep melasma. This is especially dangerous for people living in tropical areas like Vietnam, where UV rays are strong all year round.
Using vitamin C incorrectly can cause skin to age faster.
- Combining vitamin C with incompatible active ingredients
A point that is often overlooked is combining vitamin C with incompatible active ingredients. According to international dermatologist Shereene Idriss, if vitamin C is used with niacinamide at high concentrations, it can cause an antagonistic reaction or skin irritation, especially for sensitive skin.
In addition, mixing vitamin C with AHA/BHA without understanding the pH mechanism can destabilize the active ingredient structure, reduce effectiveness, and increase the risk of irritation.
- Increasing Vitamin C Too Quickly
Skin needs time to adapt, and increasing vitamin C concentrations too quickly, such as from 10% to 20%, is also a serious mistake. According to an analysis by the International Journal of Dermatology, doses that are too high can disrupt the skin's natural protective barrier, causing redness, burning, and peeling. Not only that, but long-term skin damage can lead to post-inflammatory hyperpigmentation, causing dull skin that is difficult to recover from.
- Improper storage
Equally important is improper storage. Vitamin C should be kept in a dark glass bottle, in a cool place, away from direct sunlight. A study by the University of Oregon found that vitamin C can lose up to 70% of its activity if exposed to air and light after just 8 weeks.
To maximize the effectiveness of vitamin C and avoid unfortunate risks, Dr. Kunin recommends starting with a low concentration product (5-10%), using it in the morning with a sunscreen with SPF 50+. Always monitor your skin condition in the first 2-4 weeks and switch to a higher concentration when your skin has adapted. In addition, you should choose a product with stabilization technology such as MAP (Magnesium Ascorbyl Phosphate) or SAP (Sodium Ascorbyl Phosphate) if you have sensitive skin.
Vitamin C is a powerful ally for healthy, beautiful skin, but only if you understand and use it correctly. Don't let mistakes in your skin care routine turn the "savior" into the "culprit" that accelerates the aging process and makes you lose confidence in your own skin.
(According to Byrdie, Women's Health Magazine)