Plant-based Dietary Intervention for Treatment of Acne

Acne is the most common skin disorder in the United States. Although many cases are transient, the condition is often chronic, causing self-consciousness and social stigmatization over the short term and physical scars and damaged self-esteem over the long term. Patients and clinicians have frequently attributed acnegenesis to diet; studies of varying quality have been published on the topic since the 1830s. Recently, well-designed, controlled, prospective studies suggest an acnegenic effect of specific dietary factors, including high-glycemic-index foods and dairy products. Limited evidence also suggests an acnegenic effect of foods containing saturated fats. More well-designed, randomized, controlled trials are needed to further establish dietary effects on acne. Based on epidemiologic observations and results of prior clinical trials, we are conducting a pilot study to determine if a low-fat, low-glycemic-index vegan diet affects the number of acne lesions and acne severity.

Inclusion criteria

• Male or female gender
• Mild, moderate, or severe acne, as indicated by an Evaluator Global Severity Score (EGSS) score of 2, 3, or 4
• Presence of at least 10 inflammatory or 20 non-inflammatory lesions on the face
• Presence of acne for at least 3 months (by volunteer's history)
• Age at least 18 years
• Ability and willingness to participate in all components of the study
• Willingness to be assigned randomly to a low-fat, vegan diet or a control group
• Intention to remain in the Washington DC area for the 16-week study period.

Exclusion criteria

• Change in use or dosage of hormone-based contraceptives in the last 3 months or anticipated change during the study period.
• Use of depot medoxyprogesterone contraception
• Use of oral retinoids in the last 6 months
• Use of high doses of vitamin A in the last 3 weeks (≥ 10,000 IU)
• Use of oral antibiotics or topical antibacterial or retinoid agents in the last 1 month
• Presence of more than two nodules or cysts on the face or more than two nodules or cysts on the back and chest.
• Use of medications known to cause or exacerbate acne including lithium, oral or injected steroids, or medications containing iodides or bromides
• History of alcohol abuse or dependency followed by any current use
• Current or unresolved past drug or alcohol abuse
• Facial hair that would interfere with making acne assessments
• Pregnancy or breastfeeding (currently or in the past 3 months), or intent to become pregnant in the next 4 months
• History of severe mental illness within the past 3 years
• Unstable medical status
• Current dietary pattern that is low-fat and vegan
• Anticipated difficulty attending or participating in group sessions
• Inordinate fear of blood draws
• Diabetes treated with insulin or any other medications.