What is skin sensitization? Differences from skin irritation caused by cosmetics

What is sensitization?

Sensitization is the beginning of the process by which a person develops an allergic reaction to a food or substance, which occurs when the person's immune system mistakenly identifies that food or substance as something "fearsome."

Once you recognize a food or substance as something scary, you will experience an allergic reaction every time you come into contact with it.

Not everyone will develop an allergic reaction even if they come into contact with the same allergen, and some people may not experience any allergic reaction at all even if they come into contact with the same allergen.

However, when an allergy develops due to cosmetics, it usually starts with skin sensitization.

Causes of skin sensitization

Sensitization does not only occur through eating food. Sensitization can also occur through skin contact with cosmetics, ointments, etc.

For example, applying oils or creams containing peanut oil to babies with skin problems may increase their risk of developing a peanut allergy, according to a study of 13,971 infants.

Children at highest risk of sensitization were those with a family member with an allergic parent or sibling.

It has also been reported that oat and wheat allergies , as well as peanut allergies , can develop in a similar manner.

The difference between skin sensitization and irritation

Cosmetics for sensitive skin are generally made using ingredients that are less likely to irritate the skin. However, just because the ingredients are less likely to irritate the skin does not mean that skin sensitization will not occur.

In other words, even if an ingredient is "gentle" and does not irritate the skin, it is possible that it can cause sensitization through contact with the skin.

Skin irritation and skin sensitization are characterized by the following symptoms: Because the symptoms are the same or very similar, they are sometimes mistaken for the same thing.

• Skin redness
• itch
• Itchy dryness
• rash
• Skin peels off
• Simultaneous occurrence of multiple symptoms listed above

Both skin sensitization and skin irritation are called "contact dermatitis." However, physiologically, skin sensitization and skin irritation are completely different.

What is skin irritation?

"Skin irritation" is temporary damage to epidermal cells. It is caused by skin contact with ingredients contained in cosmetics, etc. Therefore, symptoms appear where the product was applied.

For example, if after using cosmetics containing a certain surfactant, the area where you applied the product becomes red and itchy, this is likely a symptom of skin irritation.

Some people are more sensitive to the same substance than others, but everyone can be irritated.
Also, the type, severity, and duration of symptoms may vary depending on where you apply the medication.
Once contact with the substance is stopped, the symptoms will go away and you will be cured.

What is skin sensitization?

On the other hand, "skin sensitization" is an inflammatory immune response, also known as allergic contact dermatitis, that begins when you come into contact with a certain substance.
You may feel irritation on your skin, but you may not notice any symptoms right away. This is because the product or ingredients cause an allergic reaction, triggering your body's immune system to go out of control.

Repeated contact with the same substance can eventually trigger an allergic reaction, so it is possible that you may suddenly develop an allergic reaction to a cosmetic product that you have been using regularly for many years.

Only some people develop allergic reactions due to skin sensitization, but once you have been sensitized, you will develop an allergic reaction every time you come into contact with the same substance.

Allergic contact dermatitis develops through an induction period and a provocation period.

• Induction phase: The immune system forms special proteins after using a product that contains the substance.
• Induction phase: When you come into contact with the same substance later, the protein reacts and causes allergic symptoms.

Symptoms do not always appear in the area where they were applied. After applying to the face, symptoms often appear all over the body. Also, people who are sensitized to a certain substance may react to similar substances.

Skin sensitization assessment is mandatory

Cosmetics are used almost every day, and the invisible risks are impossible to measure.

For this reason, skin sensitization evaluation is mandatory for all cosmetic ingredients. If a cosmetic ingredient is highly sensitizing to the skin, the risk of allergies is also high. Therefore, depending on the results of the evaluation, restrictions may be imposed on the amount and concentration of the ingredient.

However, even if an ingredient has been evaluated as safe, there is still a possibility that an unexpected allergic reaction may occur.

For example, PEG (polyethylene glycol) , which is frequently used in many cosmetics, is generally considered a safe ingredient.
However, there have been cases of women who have suffered anaphylactic shock after receiving a vaccine that contained PEG. It has been pointed out that the woman may have been unknowingly exposed to PEG in cosmetics that she used on a daily basis.

This will reduce the chances of unknowingly becoming sensitized.
I want to choose cosmetics that have as few risks as possible.