Upwards of 17 million Americans have acne. Research has been going on since the 1800s and during the 1960s research debunked the old myths that sugar, fat, and chocolate were culprits at the time. Research from the 1960s until now also show that diet does not cause acne but can exacerbate it.
Before you pour the milk out and dodge yogurt try an elimination of dairy for a few days to weeks and seek out non-dairy sources such as coconut/almond/hemp milk, other sources are kale, canned salmon/sardines, blackstrap molasses, white beans, figs, sesame seeds, bok choy, and oranges; consider taking a calcium supplement in the evening that also has Magnesium and Vitamin D.
"Acne: The Role of Medical Nutrition Therapy," Jennifer Burris, MS, RD, CDE, CNSC, CSSD; William Rietkerk, MD, MBA; Kathleen Woolf, PhD, RD, FACSM. Journal of the Academy of Nutrition and Dietetics, Volume 113/Issue 3 (March 2013), DOI: 10.1016/j.jand.2012.11.016, published by Elsevier.