Skin care must-read: The truth about acne, whitening and weak acidity

Author: Wu Yan, Chief Physician, Peking University First Hospital

Reviewer: He Yanling, Chief Physician, Beijing Chaoyang Hospital, Capital Medical University

Nowadays, cosmetics have become an indispensable part of our daily lives. They not only beautify our appearance but also enhance our self-confidence. However, improper use or selection of unsuitable cosmetics may cause or aggravate skin problems such as acne, allergic reactions and even skin inflammation.

Acne is a common skin problem that bothers many people, and its treatment period is relatively long. During the treatment of acne, patients often want to cover up blemishes with makeup to avoid affecting work and social life. However, foundation products may aggravate pore blockage, thereby exacerbating acne problems. Therefore, when choosing cosmetics, acne skin should pay special attention to the mildness and non-comedogenicity of the product.

First, you should choose products that are labeled "non-comedogenic" and "won't aggravate acne". These products are usually processed with considerations of particle texture and solvent selection to reduce skin irritation and the risk of pore clogging. At the same time, patients should continue to use acne treatment drugs recommended by their doctors to treat the disease fundamentally and avoid neglecting treatment by simply covering it up.

In addition, keeping the skin clean is also key. A facial cleanser is an optional auxiliary cleaning tool for oily or acne-prone skin. However, it cannot clean deeply inside the pores, so it needs to be combined with other skin care methods, such as using skin care products containing ingredients such as salicylic acid to help remove blockages in the pores. At the same time, excessive cleansing or the use of irritating cleansing products will damage the skin barrier, so you should choose a gentle cleansing product that is suitable for your skin type.

Figure 1 Original copyright image, no permission to reprint

As an important means to improve skin color, whitening products are favored by many consumers. However, when choosing and using whitening products, it is necessary to establish correct expectations. First of all, it is necessary to clarify that skin color is divided into intrinsic skin color and acquired skin color. Intrinsic skin color is determined by genes, while the goal of whitening products is to reduce the uneven skin color caused by external stimuli and endogenous factors, so that the acquired skin color is closer to the intrinsic skin color.

Figure 2 Original copyright image, no permission to reprint

The effects of whitening products mainly include reducing external stimulation, reducing melanin production and accelerating cell metabolism. Sunscreen products are the first step in whitening, because ultraviolet rays are an important factor in stimulating melanin synthesis. At the same time, whitening products containing vitamin C, arbutin, kojic acid and other ingredients can inhibit the production of melanin. Products containing ingredients such as fruit acid can accelerate cell metabolism and promote the decomposition and discharge of melanin.

However, in order for whitening products to work best, it is necessary to ensure that the active ingredients in the products can be fully absorbed by the skin. Before using whitening products, you should ensure that the skin is moisturized or use a sealing method (such as using it after applying a mask) to improve the absorption effect. In addition, it is also very important to choose a regular brand, understand the product ingredients and suit your skin type.

The health of the skin is closely related to the pH of its surface. Normal skin presents a weakly acidic environment, which helps control the growth of microorganisms and protect the skin from infection and inflammation. Therefore, choosing weakly acidic skin care products is important for maintaining skin health.

Strong alkaline cleaning products can disrupt the acid-base balance on the skin surface and change the normal bacterial flora of the skin. Long-term use of such products can cause dry, sensitive skin and even skin problems. Especially for older people or those with poor skin repair ability, it may take longer to restore the skin's acid-base balance, and the skin is more likely to be in a fragile state.

Therefore, it is recommended to avoid using products with strong alkalinity when choosing skin care products. For oily or mixed skin, you can choose mild products with moderate cleaning power; while for dry or sensitive skin, you should pay more attention to the mildness and moisturizing properties of the products. In addition, for housewives who frequently come into contact with detergents, they can also reduce direct contact between the skin of the hands and alkaline cleaning products by wearing gloves, etc., to protect the skin from damage.