Earlier this week, Dr. Frank Lipman cleared up some of our confusion about why dairy seems to be the next evil food group. But in the process, he raised another issue about what milk does to your skin: according to him, dairy causes acne, too. But many commenters were up in arms about the connection between milk and skin—you wanted the science, not just the anecdotal evidence.
That’s where Dr. William F. Danby, Adjunct Assistant Professor Dermatology at Dartmouth Medical School, comes in. As a practicing dermatologist and someone who’s researched the ins and outs of milk and acne (check out his site, acnemilk.com), he’s eager to clear up the issue (and your skin). We asked him a few questions to find out why dairy could be doing your skin wrong:
Can you briefly explain what is in dairy that causes acne?
Milk raises insulin levels and insulin-like growth hormone-1 (IGF-1) levels. These two polypeptide hormones work together to open the male hormone receptors—also known as androgen receptors—that turn on acne. (And this happens in both males and females.) The milk also contains several male steroidal hormones that go directly to those open receptors…So it’s Nature’s Perfect Food for making acne.
Does the dairy-acne link have anything to do with the use of antibiotics or growth hormones in cows? Would switching to organic, hormone-free, antiobiotic-free, grass-fed dairy prevent skin problems?
The hormones that are in organic milk are the ones that are in all milk, including human mother’s milk. These are anabolic steroids and are designed to make babies grow, whether cow babies or human babies. The hormone that was injected into cows for several years, bovine somatotropin (BST) or recombinant bovine growth hormone (rBGH), is now used less and less (major thanks to Wal-Mart for stopping selling milk produced with it).
Does all dairy cause acne, or is it only certain products? (i.e. would yogurt or certain dairy products be more ok than others?)
I’ve seen patients with acne caused by every kind of dairy product, with the possible exception of well-cooked pizza cheese. I suspect, but cannot yet prove, that the heat “denatures” the polypeptide hormones and neutralizes them.
Why doesn’t dairy cause acne for everyone?