Scientists use the term exposome to refer to everything we’re exposed to in our lifetimes that might affect the health of our skin and bodies. Each of our exposomes looks a little different, so it can be difficult to clearly identify exactly what might be causing someone to break out. How do you control for diet, pollution, toxins in utero, toxins out of utero, pesticides, other diseases, seasons, and skincare regimens, for example, if you’re trying to test for the influence of, say, dairy on acne?
The question has stumped researchers for decades.
It’s like pointing to specifically what is causing the ill health of the ocean: is it pollution? climate change? overfishing? industrial mining? or a combination of all of these? And to what extent does each of these factors contribute to the whole?
So scientists haven’t determined with certainty that dairy causes breakouts. But there have been many studies and a whole lot of anecdotal evidence that suggest it’ can be at least part of the problem.
One study, presented at the American Academy of Dermatology Residents and Fellows Symposium in 2015, found that in a group of several hundred teenagers, the ones who drank skim milk were more likely to have acne. (Interestingly, full-fat milk did not seem to be linked to skin problems.) The limitation of the study is a familiar one in science: that correlation, or association, does not determine causation.
Another study, presented at the European Academy of Dermatology and Venereology Congress, found that among more than 6,700 participants, nearly half with acne consumed dairy daily. This study found that proteins in dairy “may result in inflammation,” which “may lead to acne.” Again, the same limitation emerged: the study didn’t find that dairy causes acne, only that the two are linked.
Some scientists think the artificial hormones injected into cows are correlated with breakouts. Others think milk disrupts insulin levels. Others think the sugar in milk causes skin issues. Still others, like those who represent the American Academy of Dermatology, don’t recommend changing your diet as a means of managing your acne at all. They say there’s insufficient evidence to justify a change in diet, which seems to fly in the face of a great deal of lived experience.
But until we have definitive data, it’s a good idea to consume low glycemic, high-protein foods -- kale, sweet potatoes, lemon, pumpkin, berries, papaya, quinoa, cauliflower, salmon -- that have been found to counteract breakouts. It’s also helpful to use natural skincare products and to look after your health in general: get enough sleep, reduce stress, drink water, sweat.
And the best way to find out for yourself if dairy is making your skin worse is to cut it out for a while, and see what happens. That’s our non-clinical advice.