Acne vulgaris is a common disorder affecting adolescents and adults. The rise in incidences of acne in the United States may relate to the Western diet--which is rich in dairy and refined sugars, and high in glycemic load--and to the obesity epidemic. Evidence exists highlighting the association of acne and high glycemic loads, certain dairy products, and refined sugar product ingestion.
Historically, the relationship between diet and acne has been highly controversial. Before the 1960s, certain foods were thought to exacerbate acne. However, subsequent studies dispelled these alleged associations as myth for almost half a century. During the late 1800s and early 1900s, diet was commonly used as an adjunct treatment for acne. During the 1960s, however, the diet-acne connection fell out of favor.
Studies investigating diet and acne's relationship
Several studies during the last decade have prompted doctors to revisit the potential link between diet and acne. Compelling evidence exists that high glycemic load diets may exacerbate acne. Dairy ingestion appears to be weakly associated with acne, and the roles of omega-3 fatty acids, antioxidants, zinc, vitamin A, and dietary fibre remain to be elucidated.
Although the total number of studies conducted within the past 40 years is relatively small, the growing body of epidemiologic and experimental evidence suggests a relationship between diet and acne. Compared with other dietary factors, more research examines dietary glycemic load. The evidence is more convincing for high glycemic load diets, compared with other dietary factors.
To date, there are no randomized controlled trials investigating the relationship between frequent dairy or milk consumption and acne. Similarly, the number of research studies examining the relationship between dietary fat and/or n-3 fatty acids is sparse and the evidence is less robust.
The association between soy protein and acne vulgaris has long been suggested but remains unproven in western medicine. Soy affects androgen levels, which are related to hormonal acne. However, the evidence related to soy and acne is anecdotal, and it is hard to test to see if soy protein is affecting a particular person. Perhaps one can cut it out of his or her diet for a month and see what happens
Acne has substantial effects on quality of life, making treatment essential. Medical nutrition therapy as a potential treatment for acne is not new, although the literature examining diet and acne during the past 100 years is mixed. The best dietary approach is to address each acne patient individually, carefully considering the possibility of dietary counselling.
