The kojic acid is an inhibitor of pigment formation in living tissues of animals and plants. It is a substance derived from the fermentation of different fungi. It is natural and nowadays you can find it in various cosmetic products to lighten the skin. Its effects are similar to glycolic acid, although it has some differences.
What is kojic acid
Derived from fungi, it is a relatively new natural product. It was discovered in Japan in 1989 and comes in the form of a white powder. Its structure consists of small crystals that act upon contact with the skin.
Sake contains it as a byproduct. It appears in large quantities during the fermentation of rice. Nowadays, you can buy kojic acid powder, although it is more common to purchase it as an ingredient in a cosmetic product. It is generally mixed with other active ingredients to provide a greater number of effects and benefits.
It is mainly used to lighten and remove skin spots. Hyperpigmentation is its primary target. It helps reduce the accumulation of melanin that the skin produces, which makes the face look unattractive.
The advantages it has are that its side effects are much milder than other chemicals used for the same purposes. It is used for melasma, dark skin patches that appear on the face due to sun exposure, and as a cosmetic peel.
Properties
- Anti-stain for the skin.
- Inhibits melanin formation.
- Whitening.
- Antioxidants.
- Antibiotic.
Kojic acid affects melanocytes. It inhibits the formation of melanin in the skin by halting the synthesis of L-TYROSINE. This causes lightening in the areas where it is applied or comes in contact. Additionally, it has antioxidant properties. It is effective against free radicals, so its use in anti-aging creams is recommended.
It is common to find creams with glycolic acid enhanced by kojic acid. These can be used as a peel or whitening agent for the skin as they are effective against sun spots on the face and body areas.
It is important to mention that when using this type of acid on the skin, care must be taken and precautions must be followed. They are very irritating, and after use, the epidermis becomes highly sensitive and unprotected. Peeling and redness may occur depending on the concentration of the product and your skin’s sensitivity.
Kojic acid can be used at 2% concentration with certain safety. Above 5% it is dangerous, similar to glycolic acid.
Side effects
The most common effect is mild irritation upon contact with the skin. Since it is sold in very diluted form, its use is generally safe. However, inhalation and ingestion are very dangerous to health. That is why it is common to use the properties of kojic acid in already prepared cosmetics.
People with very sensitive skin may experience slight itching or redness, even irritation. For the rest of the people, these unwanted effects are rare when using creams or cosmetics. If you buy kojic acid in powder form, its purity will be different, and its handling as an application must follow certain guidelines to make it safe.
Some cases of reactions due to prolonged use of this product have also been reported. These manifest as skin rashes, redness, and itching. If any of these symptoms occur, you should stop using it immediately.
Side effects include:
- Cell mutation
- Damage to organs such as the liver, kidneys, etc.
- Cardiovascular diseases.
- Gastrointestinal problems.
- Difficulty breathing.
It should be noted that these cases have been detected with very high doses in animal studies. At normal doses, no symptoms beyond small reactions due to possible allergies have been detected. This can be solved by stopping the use of the product. Still, it should be pointed out that the Know your environment EWG indicates that further studies are needed to investigate possible contraindications and harmful effects in humans.
Also, creams containing it and available in the European Union, the United States, and even from Japan are safe. You must follow the instructions, but this is the same as with other cosmetics. Read the directions and apply it as instructed to see how your skin improves every day.
Hello, good afternoon. Where can I find kojic acid in Medellín, and how much does it cost? Thank you very much.
If I make that mask, how long should I leave it on my face? And can it be removed with water?
How long can I use kojic acid, and what quantity should I use if my skin is sensitive? Also, at what time of the day or how often should I use it?
Can I wear makeup while using this kojic acid product?
Yany, you should follow the instructions of the product you purchase, depending on its concentration, whether it includes other depigmenting agents or if it’s pure.
Regarding the use of kojic acid and makeup, there should be no issues, but be cautious if your skin is irritated, as it may sting when applying foundation or other cosmetics. The less you use them during this time, the better, as it will allow your skin to be more oxygenated and suffer less.
Can the 25% kojic acid peeling be left on the face overnight?
Hello Cris, at those percentages, kojic acid is not recommended. The maximum recommended concentration is 5%, and preferably in cream form.
Can kojic acid be mixed with lemon juice, tomato juice, cucumber juice, onion juice, strawberry juice, pineapple juice, parsley juice, and potato juice all together to lighten the skin?
Hello. I advise you not to use all of those together. Just use kojic acid, and at 5%. Do not exceed this percentage. It’s better to be cautious, as it could be counterproductive.
You should not wear makeup.
How long does it take to see results? Do I need to use it all the time?
Hello Thelma, it depends on whether you are using it alone or as part of a cream.
What cream would you recommend I buy in New York, United States, that contains kojic acid and is easy to find?
There are many brands; some include it in small amounts to enhance the effects of other ingredients in the cream, or it can be used alone, like kojic acid for peeling. What do you want to use it for? To remove superficial marks caused by acne or sunspots on the face…?
I’m from Miami, and I want to buy kojic acid.
Good afternoon, can kojic acid solution be applied directly to the skin on my leg? Thank you.
You need to check the concentration or purity, which is usually 2% or less, but it’s common to use it topically, applied to the skin. If you’ve bought it for this purpose, there should be no issue as long as you follow the application times. It doesn’t matter if it’s for the face or legs as you mentioned; its effects are the same, but always make sure of the percentage to avoid being too aggressive.
Hello, I’m Perla. Actually, my knees are very dark, and I would like to know the best product for this and what percentage. Thank you
You can use a depigmenting cream or an exfoliant to help with the regeneration of the skin on your knees. Kojic acid has these properties, but glycolic and mandelic acids are also useful. Use it with caution and avoid sun exposure.