A survey of identical and fraternal twin pairs at the Twins Days Festival in Twinsburg, OH, and published in the April issue of the Journal of Drugs in Dermatology, shows acne may be primarily caused by genetics. Study findings show the proportion of pairs where twins have acne was significantly higher in identical (64 percent) versus fraternal (49 percent) twins.

“Since identical twins have the same genetic makeup, they make the perfect study group to see if acne is caused more by genetics or environmental factors,” explains dermatologist Elma Baron, MD, professor of dermatology at Case Western Reserve University, Cleveland, and chief of dermatology at Louis Stokes Cleveland VA Medical Center.

Participating in the survey were 202 (101 pairs) identical and 53 (26 sets) fraternal twins, including one set of fraternal triplets. Both groups were young, predominantly female and the majority of the participants were Fitzpatrick Skin Types II or III. The survey was conducted at the 2016 festival.

Researchers also attempted to determine social and environmental factors that influence acne severity. A twin-to-twin analysis of 56 identical twin pairs who had acne yet differed in self-reported severity revealed differences that may serve as triggers, including a high-glycemic diet, higher BMI, and lower frequency of exercise compared to twins without acne.

“There is some suggestion that factors other than genetics may contribute to acne severity,” says Dr. Baron in a news release. “As was demonstrated in our study and others, people genetically predisposed to acne can reduce the intake of sugar and refined carbohydrates to help keep acne on the mild side. Using cosmetics that are non-comedogenic can also help reduce acne severity.”

Survey participants were also asked additional health questions to discover possible associations with other health conditions. Identical twins with acne were found to have a higher incidence of polycystic ovarian syndrome (PCOS), anxiety, and asthma.

“Other studies have linked acne with PCOS and anxiety, but further research is needed to determine if there is a true association between acne and asthma,” Dr. Baron adds.