Many of my patients have a love-hate relationship with milk: love how great it tastes, but hate how it causes acne. But does milk really irritate the skin or cause acne for everyone? Let’s look at what the research says.
The link between milk and acne has been studied since the mid-1960s. In fact, the first-ever study linking acne with diet showed that out of 6000 participants, those with acne consumed 50-300% more milk then those who didn’t. Further, when asked to limit their dairy intake, their skin improved rather significantly.
What about today? Studies reflected by the American Academy of Dermatology Association indicate that women who drink 2 or more glasses of milk (including skim milk) a day are 44% more likely to develop acne. Even from other studies done in different countries (USA, Italy, Malaysia) across different ages (9-15 years old, 10-24 years old, 18-30 years old) the general consensus is that both males and females with acne drink significantly more milk than those without acne.
By now, the evidence should be clear: milk does carry a risk of causing acne. But why? There are a few theories.
Some physicians believe that apart from genetics, the pathogenesis of acne lie on hormones — think increased sebum secretion, inflammation and the such. It’s found that cow’s milk contains progesterone and other hormones, and it’s believed that some of these hormones cause inflammation in the body. Inflammation can lead to the clogging of your pores, thereby causing acne.
Moreover, the enzymes needed to convert these hormones to dihydrotestosterone (DHT), an androgenic hormone that plays a pivotal role in acne pathogenesis, are present in sebaceous glands. Taking these things into consideration together, the potential link between hormones in milk and acne is too strong.
While some researchers agree that dairy may be linked to acne, it is not hormones in milk that are responsible but rather growth hormones in our body, specifically insulin-like growth factor (IGF-1). IGF-1 is a hormone that promotes bone and tissue growth. It is released when we consume milk and is also known to trigger breakouts. High IGF-1 levels increase comedogenic androgenic production, which stimulate oil and cause acne. Further, high IGF-1 levels promote growth of all tissues, including follicles. This can all be confirmed by some patients with adult acne; they have high IGF-1 levels and elevated androgen levels.
Interestingly, iodine in milk has also been proposed to contribute to acne pathogenesis. This is due to the high levels of iodine in milk, and iodine is known to aggravate acne. It is believed that high milk and iodine intake may worsen acne for those already predisposed to acne.
Despite the literature demonstrating the link between acne and dairy consumption, it must be noted that these studies, although solid, only show an association between acne and dairy. As yet, there are no controlled trials that directly prove a causal link between milk and acne. So as with every research, take it as you wish; in this case, I recommend keeping a food log and tracking your symptoms.
If you suspect milk is the culprit behind your breakouts, you may want to consider eliminating milk from your diet or reducing your intake for a while. And if milk isn’t what’s causing your acne, then it means there are other factors at hand, such as other trigger foods, hormone levels, stress, or even genetics.
The cause of acne is usually multifactorial; sometimes recurrent breakouts could mean bigger health problems. If you often deal with active acne breakouts that won’t go away despite efforts, I suggest seeking advice from a doctor or dermatologist.