Ingredients Of Freckle Remover Cream​

As a skincare manufacturer with 20 years of experience, Yunmei Cosmetics has a deep understanding of ingredients. We also know that the development of freckle-removing and whitening cosmetics has always been a focus for many domestic and international cosmetic companies, with freckle-removing and whitening ingredients constantly being innovated. The main function of freckle-removing and whitening ingredients in cosmetics is to inhibit the activity of tyrosinase, promote epidermal shedding, and accelerate the excretion of melanin, thereby achieving the effect of freckle removal and whitening. Let's first understand the causes of freckle formation and the main ingredients of freckle removal cream.

1. Causes of Spot Formation

Menstrual Cycle

Some freckles are related to the menstrual cycle; women are more prone to freckles than men.

Melanocytes

Freckles are related to increased tyrosinase activity in melanocytes. In addition, sunlight, X-rays, and ultraviolet rays can increase the formation of freckles by increasing melanocyte activity.

Freckles Related to Aging

As we age, metabolism slows down, and lipofuscin is more likely to accumulate on the skin surface, forming freckles. Freckles are more common in women over 30.

Genetic Causes

Autosomal dominant inheritance is the main cause of freckles. Freckles typically begin around age 5, are more common in women, and are more pronounced in spring and summer, and less so in autumn and winter. They appear as light brown to yellowish-brown spots, ranging in size from pinhead to rice grain, symmetrically distributed on the face (especially the nose).

Endocrine Factors

Hormonal imbalances are a significant cause of freckles in women. Fluctuations in sex hormone levels during menstruation and pregnancy can affect melanin production. Additionally, hormonal instability often leads to mood swings, which can indirectly contribute to freckle formation.

Ultraviolet Radiation

Sunlight's ultraviolet radiation is a major cause of freckles, which is why sun protection is essential in summer. When skin receives excessive sunlight, the epidermis produces more melanin granules, which absorb ultraviolet rays and protect the body from harm. This explains why skin tans after sun exposure. Furthermore, ultraviolet radiation can darken melasma and common freckles.

Lifestyle Issues

Stress, unbalanced diets, and insufficient sleep can also increase melanin production. Therefore, people with irregular sleep patterns often have poor skin metabolism, affecting melanin production.

2. Types of Spots

Freckles

Freckles have a genetic predisposition and can appear in early childhood, becoming more noticeable with age. They are multiple, independent, small brown spots, commonly seen in people with fair skin. They appear on sun-exposed areas such as the face, back of the hands, and chest. They tend to be more pronounced in summer and lighter in winter, appearing darker in summer and lighter in winter.

Sunspots (Solar Melasma)

Sunspots often appear between the ages of 20 and 30. They are caused by excessive melanin production due to prolonged and repeated sun exposure. Sunspots are mostly 5-15mm or larger brown spots or patches. They appear on sun-exposed areas such as the face, back of the hands, and chest. Unlike freckles, they worsen in summer and do not lighten in winter.

Seborrheic Keratosis (Age Spots)

Age spots are common in middle-aged and elderly people, mainly related to sun exposure and photoaging of the skin. They appear as yellowish-brown patches on the face, back of the hands, and forearms, with clear borders, some of which may protrude from the skin surface. However, it's important to note that young people can also develop age spots if they don't take precautions against sun exposure!

Café-au-lait spots

These usually appear shortly after birth or during childhood and gradually grow larger with development. Café-au-lait spots appear as flat, evenly colored, well-defined brown to dark brown patches. They are usually solitary; multiple café-au-lait spots may indicate a hereditary skin condition.

Acquired Dermal Melanocytosis (ADM)

This presents as bluish-gray to grayish-brown spots or patches. It is common on the cheekbones, but can also be seen on the forehead, temples, eyelids, and nose. It is common in Asians and appears in adulthood.

Nevus of Ota

This appears in some infants under one year old and in others during puberty. It presents as unilateral or bilateral bluish-brown patches on the face, sometimes affecting the sclera on the same side.

Chloasma (melasma)

Also known as "liver spots" or "butterfly spots," melasma is more common in middle-aged and young women and is associated with high estrogen levels, UV exposure, thick stratum corneum, and medications. Typically, these spots are symmetrically distributed on the prominent cheekbones and forehead, appearing as yellowish-brown or brown patches of varying sizes and irregular shapes.

3. Common Whitening and Dark Spot Removal Cream Ingredients

Arbutin and its Derivatives

Arbutin's inhibitory effect on tyrosinase is 2 to 10 times that of kojic acid.

Mechanism of Action

Arbutin includes two isomers: α-arbutin and β-arbutin. Both isomers of arbutin are tyrosinase inhibitors. They can complex with important copper ions, thereby inhibiting tyrosinase activity and interfering with melanin production, making them effective ingredients for treating pigmentation disorders.

Safety Assessment

In February 2023, the European Union Scientific Committee on Consumer Safety (SCCS) issued its final opinion on the safety of α-arbutin and β-arbutin in cosmetics. The opinion showed that the total exposure of α-arbutin (≤2% in face creams, ≤0.5% in body lotions) and β-arbutin (≤7% in face creams) was considered safe.

Kojic Acid and its Derivatives

Mechanism of Action

Kojic acid can form chelates with metal ions, thus capturing copper ions and preventing their activation, thereby inhibiting enzyme activity and preventing melanin production.

Safety Assessment

In 2017, the International Agency for Research on Cancer (IARC) of the World Health Organization classified kojic acid as a Group 3 carcinogen. This has raised significant concerns about its safety. The Cosmetic Ingredient Review Panel (CIREP) states that a 1% concentration is safe for use in cosmetics.

A report on kojic acid published by the European Union's SCCS on March 17, 2022, concluded that considering its potential endocrine-disrupting properties, the previously permitted maximum concentration of 1% kojic acid in cosmetics is unsafe, while a maximum concentration of 0.7% is safe for consumers. The assessment showed that when the kojic acid concentration exceeds 1%, it may cause sensitization, leading to adverse reactions such as contact dermatitis, and excessively high concentrations may produce cytotoxicity.

Vitamin C and its Derivatives

Currently, commonly used vitamin C derivatives include: vitamin C glucoside, vitamin C palmitate, ethyl vitamin C, and sodium vitamin C phosphate.

Mechanism of Action

Its whitening principle lies in its ability to directly inhibit tyrosinase activity to reduce melanin synthesis. Furthermore, due to its reducing properties, it can reduce dopaquinone to dopa and prevent the oxidation of dopa back to dopaquinone.

Safety Assessment

Although vitamin C has a relatively good safety profile, excessively high concentrations may produce some cytotoxicity.

Niacinamide

Mechanism of Action

Niacinamide can alleviate UV-induced DNA damage to epidermal melanocytes and achieve skin whitening by reducing tyrosinase activity and the transfer of melanosomes from melanocytes to keratinocytes.

Safety Assessment

Niacinamide is a very safe cosmetic ingredient, but the impurity nicotinic acid in its raw materials may cause skin redness and allergies, leading to niacinamide intolerance. High concentrations of niacinamide can also cause dryness and burning sensations, and it is not easily absorbed by the skin.

Based on multiple test results, the expert panel of the Cosmetic Ingredient Review Board in the United States determined that the use of 3% niacinamide in cosmetics has no significant irritant, sensitizing, or photosensitizing effects on the skin, and niacinamide itself has no carcinogenic effects, generally considered safe for long-term use.

Cosmetics containing niacinamide have a relatively high safety profile for long-term use, but the daily dosage should not exceed 3 g. Some studies suggest that if the concentration of niacinamide in cosmetics exceeds 4%, it may cause intolerance reactions in 20% of people.

AHAs (Alpha-Hydroxy Acids) 

AHAs have the chemical structure of α-hydroxy acids and include malic acid, citric acid, lactic acid, tartaric acid, pyruvic acid, gluconic acid, and glycolic acid.

Mechanism of Action 

AHAs can enhance the skin's keratinocyte metabolism and promote the shedding of the stratum corneum. Simultaneously, melanin is also shed with the stratum corneum, thus having a whitening and spot-fading effect.

Safety Assessment 

When the concentration of AHAs is high, side effects such as skin erythema, scaling, itching, and stinging may occur, and it can also make our skin more sensitive to ultraviolet radiation.

According to research by the U.S. Food and Drug Administration (FDA), continuous use of skincare products containing 10% fruit acids (AHAs) and a pH of 3.5 for four weeks can reduce skin's UV resistance by 18%.

The Cosmetic Ingredient Evaluation Committee (CIR) in the United States has also conducted safety assessments of AHAs and recommends that AHA content should not exceed the 10% limit, and the final pH of the formulation should not be lower than 3.5.

Licorice Extract - Whitening Gold

Mechanism of Action

Licorice extract contains glycyrrhizin, which has the strongest binding affinity to tyrosinase, and can exert a whitening effect by competitively inhibiting tyrosinase activity.

Safety Assessment

Licorice extract has a good whitening effect, is gentle and non-irritating, and does not require building tolerance.

Detection Method

A rapid UPLC-MS/MS method was established for the determination of the content of seven whitening and skin-lightening active ingredients in cosmetics, including niacinamide, kojic acid, magnesium ascorbate phosphate, and arbutin.

4. Conclusion

In reality, many skin-lightening products use more than one skin-lightening ingredient. This is because a single ingredient typically only inhibits one step in the skin darkening process. To effectively control skin darkening, it's necessary to control each step; this is the "synergistic effect" whitening theory that has become popular in recent years. From this perspective, products containing two or more skin-lightening ingredients tend to be more effective.