So why have doctors always said it's a myth?
A:
Quite honestly, calling the diet and acne connection a myth just happened to catch on as prevailing wisdom after two studies were released in 1969 and 1971. The 1969 study was aimed at determining whether chocolate and acne are related. Two groups were given chocolate bars. One group was given chocolate bars with zero cocoa content, and the other group was given chocolate bars with a huge cocoa content. The two groups fared equally well as far as their acne was concerned. However, the chocolate bars both had sugar, milk, etc. The study was only testing cocoa in particular. The 1971 study asked college students, "What do you think causes your acne?" and the students were then given lots of that food. However, the students' baseline diets were not measured, there was no control group, the data was not analyzed, and the lesion count was not presented. No other studies comparing diet and acne have been performed since these two, until very recently. Obviously, from these two studies we cannot conclude that diet and acne are not related. We simply do not have the science until we perform more research. In my opinion, it is premature to say diet and acne are, or are not, related.
The recent study I referred to was performed in 2002. It was an epidemiological study and was published in the Archives of Dermatology. Dr. Cordain and Dr. Lindeberg studied indigenous tribes of hunter/gatherers, including 1200 Kitavan islanders off Papua New Guinea as well as a small group of Ache people in the remote jungle of Paraguay. There was zero incidence of acne in either population. Is this due to their diet? We are uncertain, but it is intriguing.