There are several myths about what causes acne. Chocolate, soft drinks and greasy foods are often considered to be initiators of acne outbreaks. But research has shown that foods appear to have little effect on the development and course of acne in most people. Sexual behaviors have also been linked to acne, but there is no scientific evidence to support this myth either. Another common myth is that dirty skin causes acne; but blackheads and other acne lesions are not caused by dirt. Exposure to dirt is not considered to be a risk factor for acne.

Here is an excerpt from the Brown University Student Health Services.

The exact causes of acne are unknown, but it is believed that it can result from several factors, primarily, an increase in hormones called androgens, which both males and females have. Increases in androgens cause your oil glands to enlarge and produce more oil. This oil can also change into a thick white substance called sebum. An increased oil production clogs your pores with oil and sebum that can breakdown the cellular walls in your pores, which causes bacteria to grow and pimples to develop.

Some researchers also believe that your chances of developing acne can be greatly influenced by genetics. The use of certain drugs containing androgens and lithium are known to cause acne. The use of greasy cosmetics can also lead to acne because they plug your cell follicles and promote bacterial growth.

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There are several myths about what causes acne. Chocolate, soft drinks and greasy foods are often considered to be initiators of acne outbreaks. But research has shown that foods appear to have little effect on the development and course of acne in most people. Sexual behaviors have also been linked to acne, but there is no scientific evidence to support this myth either. Another common myth is that dirty skin causes acne; but blackheads and other acne lesions are not caused by dirt. Exposure to dirt is not considered to be a risk factor for acne.

Here is an excerpt from the Brown University Student Health Services.

The exact causes of acne are unknown, but it is believed that it can result from several factors, primarily, an increase in hormones called androgens, which both males and females have. Increases in androgens cause your oil glands to enlarge and produce more oil. This oil can also change into a thick white substance called sebum. An increased oil production clogs your pores with oil and sebum that can breakdown the cellular walls in your pores, which causes bacteria to grow and pimples to develop.

Some researchers also believe that your chances of developing acne can be greatly influenced by genetics. The use of certain drugs containing androgens and lithium are known to cause acne. The use of greasy cosmetics can also lead to acne because they plug your cell follicles and promote bacterial growth.

Thus, we now KNOW how food relates to the production of acne. (Excess) Sugar increases Insulin and Insulin (in excess) greatly increases Androgens. Insulin & Androgens also increase IGF-1 (more potent than insulin, can also be increased by dairy & trans fats) which is responsible for cell growth, stimulation and thus sebaceous gland enlargement & sebum secretion. As a result of IGF-1, it's presence increases pro-inflammatory cytokines (to suppress the IGF-1), thus the presence of inflammation (may also be induced by microorganisms TRAPPED in the clogged pore).

Easy.