Date of Award


Degree Type

Selective Evidence-Based Medicine Review

Degree Name

Master of Science in Health Sciences - Physician Assistant

Department Chair

John Cavenagh, PhD, PA-C


OBJECTIVE: The objective of this selective EBM review is to determine whether or not a low glycemic index (Low GI) diet is an effective treatment for acne vulgaris in adolescents and young adults ages 15-30.

STUDY DESIGN: Systematic review of two randomized, double blind, placebo controlled clinical trial and one parallel clinical trial published in peer-reviewed journals.

DATA SOURCES: Two randomized double blind clinical trials and one parallel clinical trial published in 2007, 2012, and 2010 respectively. The sources studying the use of a low glycemic index diet as a therapeutic intervention for acne vulgaris were obtained using PubMed, and OVID databases.

OUTCOME MEASURED: Outcomes measured include acne lesion count using the Leeds grading scale with subjects holding significant power to detect a difference in the reduction of the lesions, independent dermatologist assessments, digital photographs, and subject self-assessments.

RESULTS: Kwon et al. (2012) found a significant decrease in the number and severity of lesions in the low glycemic diet group after 10 full weeks of dietary intervention. After 5 weeks of treatment significant changes were noted in patient self-assessment scores in both groups. Smith et al. (2007) found a 51% decline in mean number of total lesions in the low glycemic group as compared to 31% decline in the control group after a 12 week intervention, with differences being significant after an intention to treat model was used. The number of inflammatory lesions also significantly declined. On the contrary, Reynolds et al. (2010) found no significant difference in the number of lesion counts or acne severity after an 8-week therapeutic intervention with a low glycemic index diet.

CONCLUSIONS: Kwon and Smith et al. both showed clinical significance that a reduction in the glycemic index of dietary carbohydrates may significantly improve the severity and lesion counts in patients suffering from acne. Reynolds et al. concluded that low glycemic index carbohydrates are not responsible for changes in acne severity, and implies that other dietary factors may play a role in the development of acne vulgaris.