Acne continues to be a common skin problem beyond adolescence, as noted in a 2020 study published in JAMA Dermatology. In Western countries, around half of adults older than 25 have acne, with women being affected at a higher rate. In some people, acne develops for the first time during adulthood, while in others it is a persistence of teenage acne. Adults with acne may experience psychological consequences that include social isolation, low self-esteem, and depression.
According to the American Academy of Dermatology Association (AAD), high-glycemic foods and beverages can cause new pimples by prompting a rapid spike in blood sugar — and sugary drinks such as lattes are the worst offenders. High blood sugar drives systemic inflammation, which contributes to the development of acne. Spikes in blood sugar resulting from a high-glycemic diet also stimulate overproduction of sebum, an oily substance that can clog pores and cause acne.
In a 2012 study published in BMC Dermatology, the glycemic load of participant diets was significantly higher among a group of acne sufferers than in a control group. It was suggested that high insulin levels caused by the high glycemic load triggers the production of androgen hormones (e.g., testosterone), which then increase sebum production and acne formation.
Per the AAD, acne is reduced when high-glycemic foods and drinks are swapped for low-glycemic foods (e.g., fresh vegetables and fruits, legumes, and whole grains). For example, 87% of over 2,000 people on the low-glycemic South Beach Diet for weight loss found that their acne improved, and 91% were able to reduce their acne medications.