Acne Vulgaris: Nutritional Considerations

Some studies suggest that acne occurs more commonly in countries following Westernized diets. ^3-5 However, the role of nutritional factors remains unclear. For years, dermatologists advised patients to avoid chocolate, fried foods, and fatty foods, although proof of their pathogenic role was lacking. Acne may not be worse in individuals with a higher intake of table sugar or chocolate,⁴ although recent evidence suggests that diet may indeed contribute to hormone-related acne.

Western Diets and Acne

Indigenous populations that eat plant-based diets composed mainly (roughly 70%) of unprocessed or minimally processed foods high in carbohydrate and fiber, and emphasizing unsaturated, rather than saturated, fats (tubers, fruit, vegetables, peanuts, corn, rice), are largely free of acne. In contrast, the vast majority of teenagers and 40% to 54% of the adult (>25 years) population in Western societies have some degree of facial acne.³

Evidence also suggests that as immigrants become acculturated to a typical Western diet, their previously low incidence of acne rises to the levels found in Western societies.⁴ Aspects of diet under particular scrutiny are as follows:

Dietary fat contributes to sebum production, and excesses of both fat and carbohydrate contribute to increased lipid secretion in human skin. In contrast, restricting calories can reduce sebum production by as much as 40%.⁴

Diets high in saturated fat,⁶ meat,⁷ and milk⁵ increase blood concentrations of insulin-like growth factor (IGF-I), which, in turn, stimulates the production of androgens known to increase sebum production.^3,4 Plant-based diets, low-fat diets, high-fiber diets, and vegetarian diets lower IGF-I and increase IGF-binding proteins.^3,7,8

Dairy products may play a role in acne. In the Nurses Health Study II, more than 47,000 women completed questionnaires based on recalling their diet during high school in 1998, and associations were estimated between various food groups and diagnosis of teenage acne. Women who consumed more than 2 glasses of skim milk per day during their teen years (ie, ages 13-18) had a 40% greater prevalence of teenage acne, compared with those drinking less than 1 glass per week.^5,9

Controlled trials testing this relationship are in progress. While mechanisms that might explain the association have not been established, several possibilities have been suggested. Milk contains both hormones and hormone-like chemicals (eg, IGF-I) that may survive processing and affect the pilosebaceous glands. Apart from the hormones found in milk, hormones or growth factors may be produced in the human body in response to milk ingestion. For instance, regular milk ingestion by adults is associated with an elevation of blood IGF-I concentrations,¹⁰ which may increase the risk for acne.

Orders

See Basic Diet Orders.

Low-fat, high-fiber, nondairy diet may be tried on a prospective basis.

What to Tell the Family

Acne is a distressing condition. Some evidence suggests that it may be in some measure preventable by dietary changes. In particular, dairy intake has been associated with the development and worsening of acne in women and could also play a role in men. Likewise, a high-fat diet may be implicated in acne formation. In addition, the use of oil-based cosmetics, excessive scrubbing or rubbing, and occlusive clothing (tight bras, turtlenecks) may worsen the acne lesions. Family members can assist patients with acne by helping them stay on a healthful diet. Moreover, following such a diet themselves may reduce their own risk for diet-related conditions.