Low-Glycemic-Load Diet May Improve Acne in Young Men CME

Release Date: July 27, 2007; Valid for credit through July 27, 2008

July 27, 2007 — A low-glycemic-load diet reduced acne lesions in male
patients aged 15 to 25 years, according to the results of a randomized
controlled trial study published in the July issue of the American
Journal of Clinical Nutrition.

"Although the pathogenesis of acne is currently unknown, recent
epidemiologic studies of non-Westernized populations suggest that
dietary factors, including the glycemic load, may be involved," write
Robyn N. Smith, MD, from RMIT University in Melbourne, Australia, and
colleagues. "Recently, there has been a reappraisal of the diet and acne
connection because of a greater understanding of how diet may affect
endocrine factors involved in acne.... Hyperinsulinemia has been
implicated in acne pathophysiology because of its association with
increased androgen bioavailability and free concentrations of
insulin-like growth factor I (IGF-I)."

In this 12-week, parallel design, investigator-blinded study, 43 male
acne patients aged 15 to 25 years were randomized to receive a
low-glycemic-load diet (25% energy from protein and 45% from
low-glycemic-index carbohydrates) or a control diet rich in
carbohydrate-dense foods without consideration of the glycemic index.
Outcome measures included monthly dermatologic evaluation of acne lesion
counts and severity. Using the homeostasis model assessment, insulin
sensitivity was determined at baseline and at 12 weeks.

Mean reduction in total acne lesion counts at 12 weeks was -23.5 ± 3.9
in the low-glycemic-load group and -12.0 ± 3.5 in the control group (P =
.03). Compared with the control diet, the low-glycemic-load diet was
also associated with a greater decrease in weight (-2.9 ± 0.8 vs +0.5 ±
0.3 kg; P < .001) and body mass index (-0.92 ± 0.25 vs +0.01 ± 0.11
kg/m2; P < .001) and a greater improvement in insulin sensitivity (-0.22
± 0.12 vs +0.47 ± 0.31; P = .026).

Study limitations include the possibility that topical application of a
mild skin cleanser may have contributed to acne improvement; inability
to rule out the effect of other dietary factors, such as zinc and
vitamin A intake, on acne improvement; and reliance on self reporting of
dietary intakes.

"The improvement in acne and insulin sensitivity after a
low-glycemic-load diet suggests that nutrition-related lifestyle factors
may play a role in the pathogenesis of acne," the authors write.
"However, further studies are needed to isolate the independent effects
of weight loss and dietary intervention and to further elucidate the
underlying pathophysiologic mechanisms."

Meat and Livestock Australia supported this study.

Am J Clin Nutr. 2007;86:107-115.