There is no scientific basis for the claim that eating apples helps treat acne directly.
More Info: Apples do not contain any active ingredient that when ingested will directly treat acne. The claim and hype seems to originate from the fact that apples are nutritious and good nutrition helps to keep the body healthy.
Apple Acne Treatments
Ingesting an apple may not directly treat acne flare-ups but apple pectin may have a use as a skin- conditioning agent. For example, Biomedics lists pyrus malus (Apple) fruit extract is the main ingredient in its salicylic acid cream called Anti-Clog Concentrate. According to the drug information sheet from the National Library of Medicine, the product is designed to dry up and prevent blemishes, blackheads and whiteheads.
There may be preliminary scientific evidence to support the theory that apple fruit extracts can play a role in the treatment of acne. Researchers from the Laboratory of Pharmaceutical Microbiology, Ghent University, Belgium tested the effects of a variety of fruit extracts on Propionibacterium acnes, the bacterium that plays a role in acne formation, and found that Malus pumila, the extract from the paradise apple, was effective. [Coenye, 409]
Health Benefits of Apples
Numerous studies have concluded that apples have a wide and varied set of health benefits. Recent studies support the value of apples for weight loss, brain health, cancer, metabolic syndrome, lung health, heart health, immunity, and gut health.
“Anti-Clog Concentrate.” DailyMed. N.p., n.d. Web. 8 May 2012. <http://dailymed.nlm.nih.gov/dailymed/archives/fdaDrugInfo.cfm?archiveid=40675>.
Coenye, T, and et al. “Eradication of Propionibacterium acnes biofilms by plant extracts and putative identification of icariin, resveratrol and salidroside as active compounds..” Phytomedicine 19.5 (2012): 409-412. Print.
“US Apple Association.” Apple Health Benefits. N.p., n.d. Web. 8 May 2012. <www.usapple.org/PDF/Health%20Benefits%20Research%20Summary%207-10.pdf>.