Investigating a Potential Link Between Diet and Acne

Acne vulgaris is a complex but common skin disease that affects individuals of all ages and sexes, although, it historically has a higher prevalence among both adolescents and females.

Acne has been described as a "chronic, multifactorial inflammatory disease," resulting in the formation of lesions when pores become inflamed below the skin's surface. Causes of acne may include genetic factors, including a family history, certain medications and other factors that can influence hormone production. For example, androgen, insulin and insulin-like growth factor-1 hormones have all been associated with acne. Environmental conditions, such as high humidity, as well as stress may exacerbate this skin condition.

Various foods and beverages have been shown to influence hormone levels; therefore, the role diet plays in contributing to acne has been questioned over the years. One systematic review noted 146 foods had been identified in their literature search. More commonly cited examples include consumption of chocolate and cow's milk, fatty foods, as well as low and high glycemic foods. However, there is a lack of high-quality research available on diet and acne at this time.

Most available research consists of non-randomized studies with expert opinion, case-control or cohort studies and just a handful of randomized studies with limitations noted. Where stronger studies are available, research suggests a low glycemic load may reduce acne severity. Studies focusing on cow's milk and its influence on acne are greater in number but are based on lower quality evidence.

One of the larger studies focusing on diet and acne to date is the NutriNet-Sante Prospective Cohort Study. As part of a larger study, researchers evaluated a sample of more than 24,000 French adults, (with a mean age of 57 years), who self-reported on past and current acne alongside three, 24-hour diet records, which were obtained at baseline and six months. Of this sample, 75% of the participants were females and a little less than half indicated current or past acne. When asked about diet's influence on acne, 32% "believed that diet was a factor" versus 31% who did not, with the remaining individuals being unsure.

The researchers found that individuals who reported current acne were younger, more likely to have a body mass index less than 25 kg/m2 and lower levels of physical activity. Additionally, a significantly higher consumption of cow's milk, sugar-sweetened beverages, and higher overall intakes of fat and sugar were noted and described as being consistent with a "Western diet." They also noted lower levels of vegetable, fruit, meat and seafood consumption among those who had acne compared to those who reported no current acne, although the association was not significant after adjustments. Further analysis of the participants' dietary records suggested that a "healthy pattern," which consisted of higher consumption of seafood and produce or one that primarily included "animal products and refined cereals," were each negatively associated with acne in adulthood compared to a "fatty and sugary pattern."

While there may be a link between diet and acne, there remains a need for more long-term, prospective and randomly controlled trials. In the meantime, registered dietitian nutritionists can work with patients and clients to identify potential food triggers and develop individualized eating plans to promote overall health.

References:

• Penso L, Touvier M, Deschasaux M, et al. Association Between Adult Acne and Dietary Behaviors: Findings From the NutriNet-Santé Prospective Cohort Study. JAMA Dermatol. 2020;156(8):854–862.
• Zaenglein AL, Pathy AL, Schlosser BJ, et al. Guidelines of care for the management of acne vulgaris. J Am Acad Dermatol. 2016 May;74(5):945-73.
• Fiedler F, Stangl GI, Fiedler E, Taube KM. Acne and Nutrition: A Systematic Review. Acta Derm Venereol. 2017;97(1):7-9.
• National Institutes of Health. National Institute of Arthritis and Musculoskeletal and Skin Diseases. Acne.