- Causes of acne: Our skin has pores that open to hair follicles and oil glands. Sebum secreted by oil glands lubricates the skin, moisturizes, prevents water from escaping from the skin and also prevents the formation of bacteria.

- Skin pores that are clogged for the following reasons can cause acne:

• Bacteria accumulate in pores
• Overproduction of oil
• Dead skin accumulates on the skin
• Inflammation
• Research has shown that oily skin is more susceptible to acne due to excess oil production. Other skin types can also suffer from acne due to poor skin care habits and lifestyle factors such as a greasy diet and smoking can also clog pores.
• You are at risk of acne if you have one of the following factors:

Age: People of any age can get acne, but it is more common in teenagers.
Genetics: If both of your parents have acne, you are more likely to have acne. Our genes influence how our skin produces and secretes oil, which can lead to acne.
Hormones: Hormonal changes, especially during puberty, pregnancy, and use of suppositories, can lead to an increase in oil production and acne.
Diet: Some studies have shown that diets rich in carbohydrates, sugar, and dairy may increase the risk of acne.
Stress: Although not the main cause of acne, stress can make your condition worse.
Oil on the skin: Certain activities or jobs that involve exposure to oils and lubricants, such as cooking or working in a manufacturing plant, can lead to acne.
If you have any of the following signs and symptoms, then you have acne-prone skin:

• Clogged or clogged pores or whiteheads
• Small red to soft papules
• Simple acne
• Large nodules under the skin
• Large painful pus-filled lumps (cystic lesions)
• Redness in the affected area
• Scars from the last pimples

Source: https://www.vinmec.com/en/news/health-news/care-for-acne-prone-skin/