It is said that acne (acne vulgaris, common acne) is a common problem as far as the  teenagers are concerned; and that is why the fact is that it can affect people from ages 10 through 40. Acne problems are of so many types:
congested pores ("comedones"),
whiteheads,
blackheads,
pimples ("zits"),
pustules, or
cysts (deep pimples, boils).

Here are some factors that may be responsible for causing acne:

Heredity: With the exception of very severe acne, the fact is that not all the individuals face these problems like their parents did. But some acne are heredity causes.

Food: it is often said that children, especially who are in their teens should  avoid pizza, chocolate, greasy and fried foods, and junk food. But the fact is that these foods are not that beneficial as far as the overall health is concerned, but at the same time they don't cause acne or make it worse. According to a lot of research work, it has been stated that implicated milk and dairy products have some kind of role to play in aggravating acne, these findings are far from established.

Dirt: the fact is that the black pores that you see on your face or body are "blackheads" that are oxidized oil, not dirt.
 
Stress: Some people get so upset by their pimples that they make their stress level go higher and higher by each passing day.

Hormones: Some women break out cyclically, but most women (and men) don't. It is said that due to unusual menstrual cycle or may some other hormone symptom, pimples may occur.

Cosmetics: Most cosmetic and skin-care products are not pore-clogging ("comedogenic").
 
Pressure: In some patients, pressure from any kind of external object, may be a helmet, and the like can aggravate acne.

Drugs: Some medications may cause or worsen acne, as they may cause a lot of side effect at the same time as well.

Occupations: In some jobs, exposure to industrial products like cutting oils can be a factor that may cause acne.

Treatment:Let me tell you some of the homely treatments:
Accutane: This therapeutic product and because of its easy availability in the market, it is quiet famous and is simply given for chronic acne cases.

Topical Antibiotics
This treatment is a wealthy acne scar treatment. It is often recommended in severe cases.

Isotretinoin
It is used for chronic acne scars, but this is not generally recommended by the doctors because of its later side effects.

Aloe Vera
the best drink to remove acne, should be taken at a regular level. You can drink one table spoon of aloe vera juice everyday. Just one spoon is enough. I would recommend that you should mix it with half a table spoon of amla juice. Do yoga as well.

Wash Face Daily
in order to clean the dirt, so that the formation of pores can be prevented, it is recommended that you should wash your face everyday. I would like to recommend that you should only go for antiseptic soaps because some soaps can cause allergies.

Healthy Lifestyle
Don't eat junk food and chocolates much! No fatty food!