If you eat a high glycemic diet with foods like white bread, sugary soda, white potatoes, and white rice, you will experience insulin spikes. This we know. What we don’t know (sorry Josh) is whether this sort of diet will directly affect acne.
Scientists hypothesize that a high glycemic diet and its resulting insulin reaction will result in higher levels of hormones (IGF-1 and androgens) which may contribute to clogged pores and increased skin oil production.
When it comes to high glycemic diets in particular, scientists also postulate that eating this way may lower the amount of beneficial proteins (IGFBP-3) and natural retinoids, which help keep skin cell growth in check and pores from becoming clogged.
However, as is becoming customary in my research on diet and acne, we do not have enough research to make any strong correlations. The only 2 studies which have been done on glycemic load and acne have been performed by the same group of Australian researchers, led by Robin Smith, and while acne lesion counts appear to reduce on low glycemic diets, results are inconclusive. What stands out most sharply is the lingering question of whether glycemic load leads to decreased acne symptoms or whether it is the weight loss that tends to go hand in hand with this sort of diet that causes the reduction in acne. To answer this question, we need data on whether a reduction in acne symptoms is sustained after weight loss has leveled off. Until then, I’m happy that the scientific community is at least starting to investigate.
After a thorough review of the literature up until today…
This is what scientists know:
Hormones: Milk contains hormones such as IGF-1 (insulin-like growth factor) and androgen (male hormone) precursors.
Iodine: Milk often contains iodine, largely due to farmers dipping the teats of cows in an iodine solution before milking in order to sterilize. At large doses, iodine can cause what are called acneiform eruptions. Acneiform eruptions look similar to run-of-the-mill acne vulgaris but are different in important ways.
This is what scientists postulate, but don’t know:
Hormones: IGF-1 and androgen precursors in milk could theoretically lead to increased skin cell production, causing pores to become clogged. IGF-1 and androgen precursors could also theoretically lead to increased skin oil production. Since we know that acne does not flourish in low oil environments, perhaps the hormones in milk might help provide an oily fertile ground for acne.
Iodine: The link between iodine and acne is even more theoretical than with dairy. However, some select scientists put out the possibility that if iodine does in fact aggravate acne, since milk contains iodine, milk could lead to more acne.
The bottom line:
What stands out strongly now that I have read all of the evidence is that the design limitations in dairy and acne studies thus far leave us without any concrete answers. After performing a thorough review of existing evidence, authors in the Journal of Clinics in Dermatology agree: “Our conclusion, on the basis of the existing evidence, is that the association between dietary dairy intake and the pathogenesis of acne is slim.”
My common sense takeaway:
Northern Europeans were the first to domesticate animals and drink milk past childhood. In fact, the last genetic adaptation we see in humans is the gene which allows people of Northern European ancestry to digest lactose. If you can drink milk and eat dairy products without stomach aches, excess gas, or discomfort, perhaps ingesting dairy is part of a healthy lifestyle for you. However, for the rest of us, me included, if you do not have the gene, and dairy gives you issues, that’s a pretty clear sign that your body isn’t crazy about dairy. It might be a good idea to steer clear of it for overall health. As far as acne in particular is concerned, we just don’t know yet. I personally love pizza more than breathing 😉 and I’m not going to give up dairy completely until I see more concrete evidence linking it directly with acne or other serious negative health consequences.
Thanks for voting for what you guys wanted me to concentrate my acne research on. The last I looked at the poll results diet and acne was winning. Now I see that scars have a few more votes. Well, scars will be next. But first, let’s delve into diet and acne. In fact, let’s get deep and dirty and nitty gritty with it shall we? Yes? Great, then we shall 🙂 I’ve read every published trial and review of literature since 2008 regarding diet and acne there is good news and bad news.
Good news: Scientists are all over it! No longer is diet and acne relegated to a back seat. According to the Journal of the American Academy of Dermatology (2010), “…it is evident that dermatologists can no longer dismiss the association between diet and acne…In light of the last decade of research investigating the relationship between diet and acne, it is no longer dermatologic dogma to state that any association between diet and acne is mere myth.” In other words, researchers are conducting studies and we’re getting interesting data.
Bad news: The data is still spotty and almost all of the recent studies come with serious “design limitations” as they call them. An example of a design limitation is researchers relying on subjects’ personal recollection of their diet habits instead of actually watching what they eat. Another example of a design limitation is trusting subjects to define for themselves whether they have “acne” instead of employing a professional to count lesions across a study cohort. In other words, we can’t trust the data that’s coming out yet. We need more trials, and better trials, before we make conclusions.
Um, a little more bad news: Because pharmaceutical companies do not make money from educating the public on diet, funding for diet and acne studies is sparse. But hey, even without the pharmaceutical companies, we’re seeing a resurgence of interest in the topic of diet and acne.
My gut feeling on the subject: Regardless of whether some hunter/gatherer tribes do not have acne, it is literally impossible for us to go back to a hunter/gatherer way of living, and for real concrete answers to acne, we’ll have to include diet as only one piece of a much larger puzzle. As much as I would love for it to happen, I don’t think we’re going to find a magic bullet. I don’t think we’ll find a super bad food or food group which we’re all eating which is causing acne. I also don’t think educating people to “eat right” and “low glycemic” will clear people up to the degree any of us want.
I’ll keep updating the blog with specifics regarding some diet and acne subtopics like dairy, glycemic load, iodine, etc. for the next few updates. Hopefully with all of us wading deep into the muck of the latest research we can pool our minds and get food working for us as much as possible.