What causes pimples?

What causes pimples?

A pimple is a small papule or pustule. Pimples grow when sebaceous glands, or oil glands, get clogged and infected, leading to swollen, pus-filled red lesions.

Pimples are also known as spots or zits, and are part of acne. They are most likely to occur around puberty, but they can happen at any age.

The hormone production changes during puberty. This can cause overactivation of the sebaceous glands at the base of hair follicles. As a result, for women, pimples are most likely to occur during the teen years and around menstruation.

Pimples affect the nose, neck, chest and shoulders the most frequently. That is because in some parts of the skin there are many sebaceous glands.

Acne vulgaris, the leading cause of pimples, affects more than 80 per cent of teenagers. It affects 3 percent of males and 12 percent of females after age 25.

Important facts about pimples

Here are a few key points regarding pimples. More specifics are given in the main article.

  • Pimples range in severity, from blackheads to cysts.
  • They happen when the sebaceous glands become more active, dead skin cells clog the pores, and sometimes an infection develops.
  • Pimples often occur in adolescence, but they can affect people at any age.
  • There is not enough evidence to confirm that any particular food causes acne, but following a healthful diet may reduce the risk.


Pimples on a lady face
Blackheads, whiteheads, and cysts are all kinds of pimples, but what makes them break out?

There are various types of pimples, and they have different symptoms and signs:

Whiteheads: Also known as a closed comedo, these are tiny pimples which remain under the skin. They appear as a small papule with a flesh colour.

Blackheads: These are also known as open comedo and are clearly noticeable on the skin surface. Because of the oxidation of melanin, a skin pigment, they are black or dark brown.

Some people mistakenly believe that because of their colour, they are caused by dirt and scrub their faces vigorously. Scrubbing isn’t helping. It can irritate the skin, and trigger other issues.

Papules: Small, solid, rounded bumps which rise from the skin. They are often pink.

Pustules: These pimples are filled with pus. They are clearly visible on skin surface. The base is red, and the top pus.

Nodules: These have a papules-like structure but they are larger. These can be painful and deeply embedded in the skin.

Cysts: These are visible on the skin surface. They ‘re filled with pus and appear to be painful. Cysts can cause scars.


When pores get clogged with sebum and dead skin, pimples occur. Which sometimes leads to inflammation and infection. It’s largely unknown why they affect certain people more than others.

The sebaceous glands and pimples

The sebaceous glands are tiny sebum-secreting skin glands, a waxy or oily substance that lubricates the skin and hair.

Sebaceous glands are found all over the body, inside the pores of our skin, except the palms of the feet ‘s hands and soles. The face and scalp contain more sebaceous glands than elsewhere.

As the glands produce sebum within the pores, new skin cells are constantly growing, shedding outer layers of skin.

Dead skin cells don’t get shed sometimes. They stay in the pores, and the sticky sebum stuck together, causing blockage in the pore.

Pore blockage is more likely to occur during puberty, since at this time the sebaceous glands produce more sebum.

Bacterial infection

This encourages the growth of harmful bacteria, including Propionibacterium acnes (P. acnes), a slow-growing bacterium linked to acne, where sebum and dead skin cells accumulate and obstruct a pore.

Propionibacterium acnes exists harmlessly on our skin but it can reproduce faster and become a problem when the conditions are right. The slow-growing bacterium feeds off the sebum and produces an immune-response substance. This causes skin and spots to become inflamed.

Although the pimples are bacterial infection related, they are not contagious. One person can not catch another’s pimples.

Risk factors

It’s unknown exactly why certain people are more prone than others to pimples. Fluctuation of the hormones and genetic factors may play a role, as acne frequently occurs in families, but some other causes are likely.

Good and bad bacteria

washing your face gently
Gentle washing may help prevent infection, but scrubbing can make pimples worse.

Just as we have “good” bacteria in the gut that protect against disease and “bad” disease-causing bacteria, scientists have suggested the same can be true for the skin.

Researchers at the Washington University School of Medicine identified 20 percent of people with pimples with two unique strains of P. acnes in the skin, while those with healthy skin tended not to harbor those strains.

Another strain of P. acnes had the opposite effect. People with pimples didn’t tend to have that strain, but those with healthy skin did.

This may indicate that the severity and frequency of the pimples determines specific types of bacteria. The researchers propose that these bacteria can also interfere with various factors, such as levels of hormones and sebums. They call for more research.

Yeast infections

Breakouts of the acne-type also were linked to yeast infections.

Pityrosporum, also known as malassezia or folliculutis, occurs when a pityrosporum yeast enters and multiplies the hair follicles, causing an itchy eruption of tiny, itchy, rounded pimples, which resembles acne. It occurs mainly on the upper chest , shoulders and upper back but can also affect the face.

Most people have this yeast on their skin but it may create a problem if too much grows. It can happen in young to middle-aged men and women alike.

Humid, sweaty environments, synthetic fiber clothes and the use of oily skin products can all make that worse.

The condition is common in adolescents, likely due to increased activity of the sebaceous glands. It’s not the same as acne but often it’s confused with it.

Antibiotics commonly used for acne can also make the condition worse by suppressing the bacteria that would otherwise control the yeast. In the case of malassezia antifungal treatment is required.

Testosterone sensitivity

Researchers have discovered a connection between acne pimples and higher testosterone levels and other androgens, the “male” hormones that also occur in lower females.

Higher levels of testosterone appear to trigger greater activity in the sebaceous glands, resulting in more obstructed pores and a greater chance of acne.

Food factors

The role of diet in acne is unclear, but because it is known that a healthy , balanced diet promotes good health, some dietary factors may affect the likelihood of acne or pimples.

Nut, seed
Don’t cut out all fats from the diet. Healthful fats from nuts, seeds, and olive oil may help control inflammation.

Vitamins A, D, and E are all known to play a role in maintaining healthy skin, so an adequate supply of these vitamins may be helpful in preventing acne.

Acne has been related to milk consumption. This may be due to the hormones in milk, if milk does play a part. Findings, though, were unconclusive.

Sugar and chocolate have often been said to trigger acne but research findings did not support this.

Studies have linked a low-glycemic-index (GI) diet to lower blood insulin levels , lower androgen levels, and a reduced probability of acne.

The results are nonetheless not conclusive. Additionally, promoting a low GI diet could prevent people from consuming enough whole grains and other nutritious foods which could provide valuable nutrients.

While acne is linked to sebum production, it is not advisable to eliminate all the fat in the diet. The main bodily functions involve healthy polyunsaturated and monounsaturated fats. A fat-free or very low-fat diet can cause sebum development to dry out the skin and prompt the body to increase.

Good intake of nut, seed, and olive oil fats can help by keeping inflammation in check, supporting the body in maintaining healthy levels of blood sugar, and maintaining good levels of moisture in the skin to provide an effective barrier and immune response to prevent bacterial infection.

“There aren’t enough data to recommend dietary changes for acne patients,” according to the American Academy of Dermatology (AAD).

If dietary changes are to play a role in acne treatment, the AAD suggest that this should be as a “complement to proven acne treatments,” rather than as a sole treatment. They recommend that people monitor themselves to see what could cause a breakout

Tips include:

  • keeping a food diary, and sharing it with a dermatologist
  • waiting for 12 weeks after cutting out a particular food, as it may take time to see the impact
  • continuing with regular acne treatment while making any dietary changes

Some medical conditions, for example polycystic ovarian syndrome (PCOS), also increase the chances of pimples.

Since acne appears to be the result of a complex interaction between nutrients, hormones and other factors, it is difficult to identify exactly what causes pimples to worsen.

If acne and pimples begin to affect the quality of life and self-esteem of a individual, a doctor or dermatologist may sometimes be of help.