Milk intake correlates with increased risk of acne in women

Question Does milk intake increase the risk of teenage acne?

Synopsis Most, if not all, teenagers are concerned about acne and what they can do to prevent or minimise it. These investigators analysed data from the nurses health study, a prospective cohort study of 47 355 US nurses with greater than 90% follow-up. Participants with self reported “severe” acne (approximately 40% of the cohort) filled out a survey evaluating their food consumption between the ages of 13 and 18. The diet questionnaire was validated in a small subcohort of subjects, but most participants completed it after more than nine years had passed. Intake of whole milk and skim milk intake was significantly associated with an increased risk of acne. The odds ratios ranged from 1.16 to 1.44. There was no significant correlation with soda, french fries, pizza, or chocolate candy. Skim milk intake was more strongly associated with an increased risk of acne than whole milk. The authors report only the body mass index and onset age of menses for the subjects; no other demographics are noted (eg, race, birth control usage). Possible reasons for the association include the potential of hormones being in the milk, and whey proteins. It is uncertain if soy milk or hormone-free milks would produce different results.

Bottom line Whole milk and skim milk intake are associated with a slightly increased risk of teenage acne. This study design cannot prove causation, and we have no evidence that decreasing intake will improve acne. It is important that teenage women have an adequate intake of calcium and vitamin D to help bone growth and formation. Although a number of non-dairy products with added calcium have been introduced, we should not recommend decreasing the intake of dairy products to reduce the risk or severity of acne until we have better evidence.

Level of evidence 2b (see www.infopoems.com/levels.html). Individual cohort study or low quality randomised controlled trials (< 80% follow-up)