According to MedlinePlus, a service of the US National Library of Medicine, acne is a common skin condition. The exact causes of acne are not known, but key factors include inflammation, excess oil, clogged pores and bacteria. Teenagers are most susceptible to acne; however, anybody can suffer from it. There is a list of foods you should avoid if you have acne, as some can irritate the skin, worsening the condition.

Milk

According to Science Daily, dermatologists seem to agree that something in milk products may be associated with acne formation in teenagers. However, pinpointing the exact causes of the substance in milk producing acne is difficult to define. A study performed by the "Journal of the American Academy of Dermatology" found that hormones or bioactive molecules in milk is related to teenage acne.

Processed Foods

According to Planet Green, process foods contribute to the development of acne formation. These foods contain synthetic colors and added preservatives, and too much consumption of these ingredients affects the liver, leading to an excess of toxins and as a result, acne breakouts. The best way to avoid process foods is to monitor your intake of produce from fast food restaurants.

Omega-6 Fatty Acids

Excess consumption of omega-6 fatty acids can lead to an increase in redness and inflammation. Pro-inflammatory hormones are beneficial for you, as they help to protect your body from bacteria and viruses; however, too much of these hormones irritate acne, making it worse, according to Acne Online. Omega-6 fatty acid foods to avoid include ham, cheeseburgers, pork sausage patties and bacon.