Almost half a century ago, two small studies on diet and acne that would turn out to greatly influence the evolution of the field of dermatology, in particular the parts of the field that deal with acne vulgaris, a skin disorder that is today highly prevalent in westernized nations, were published (1, 2). Those studies, which found no clear association between the consumption of certain “modern foods” such as chocolate and the development of acne, contributed to imprinting the widely held notion that there is no relationship between diet and acne into the minds of countless dermatologists and other health professionals.
Still, to this day, many, if not most, doctors and dermatologists operate under the belief that the food we eat don’t noticeably impact our sebum production, the growth of the acnegenic skin bacterium Propionibacterium acnes, or the development of acne lesions. This is very concerning, because as anyone who’s kept up with the research in this area will tell you, there is actually a relationship between diet and acne. Not only that, but the relationship is quite strong; it’s not weak or inconsequential, as some people seem to think.
The reality is that there is actually very little we can learn from the aforementioned old studies, seeing as they only shed light on some (tiny) aspects of the diet-acne relationship and were designed and conducted in a less than ideal manner. The primary takeaway from the story of how those studies, as well as other similar experiments, influenced the dermatological community is not that there is no link between diet and acne, but rather that one should be careful when one interprets the results of scientific research. If enough people jump to erroneous conclusions, entire disciplines may be led astray and many people may suffer as a result.
Accumulating research affirms that acne vulgaris is a diet-related disease of civilization
Not so long ago, I put up an article here on the site in which I made the case that acne vulgaris is a disease of civilization that develops largely as a result of diet-genome mismatches, as well as microbiome-genome mismatches. In support of that statement, I presented evidence showing that non-westernized, traditional people tend to have acne-free skin; that acne prevalence rates track closely with degrees of westernization, with higher prevalence corresponding to increased westernization; that dysbiosis and unhealthy eating adversely affect skin health; and that various types of probiotics and dietary interventions are useful in the treatment of acne vulgaris.
In today’s article, I’m not going to do this all over again. Rather, the reason I chose to put up this article is that I very recently – just a few days ago actually – came across a new and very interesting paper on the diet-acne link. This paper is the latest in a series of scientific articles and experiments that together leave no doubt that there is indeed a strong relationship between diet and acne (Some of the articles: 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13).
Instead of breaking down the research myself, I thought I’d include the abstract of the paper, which nicely summarizes what this research is all about. (Bold: My emphasis)
Acne vulgaris is an epidemic inflammatory disease of the human sebaceous follicle and represents the most common skin disease affecting about 85% of adolescents in Westernized populations. Acne vulgaris is primarily a disease of wealthy countries and exhibits higher prevalence rates in developed compared with developing countries. No acne has been found in non-Westernized populations still living under Paleolithic dietary conditions constraining hyperglycemic carbohydrates, milk, and dairy products. The high prevalence rates of adolescent acne cannot be explained by the predominance of genetic factors but by the influence of a Western diet that overstimulates the key conductor of metabolism, the nutrient- and growth factor-sensitive kinase mTORC1. Increased mTORC1 activity has been detected in lesional skin and sebaceous glands of acne patients compared with acne-free controls. Increased mTORC1 signaling is a characteristic feature of insulin resistance, obesity, type 2 diabetes mellitus, cancer, and neurodegenerative diseases. Acne vulgaris is a family member of mTORC1-driven diseases of civilization and represents the MetS of the sebaceous follicle. (13)
As you can see, the author of the paper, Bodo Melnik, argues that modern, western foods, in particular milk and highly processed, sugary foodstuffs, drive the development of acne vulgaris by influencing insulin production and mTORC1 signaling. When Bodo Melnik speaks up about something like this, it’s wise to pay attention, seeing as he’s one of the – if not the – world’s foremost experts on milk as it relates to nutrition and health and the pathogenesis of acne vulgaris.
Let’s not forget the microbiome…
In the past, I’ve made the case that widespread microbiome destruction is a primary driving force behind the acne epidemic. This is a statement I stand by. I don’t doubt for a second that the things Bodo Melnik talk about in the above paper are important with respects to the pathogenesis of acne; however, I think it’s crucial not to overlook the role of the microbiome.
Dysbiosis of the gut sets the stage for immune dysfunction, increased intestinal permeability, and inflammation, which in turn negatively affects skin health, including skin microbiota composition. This idea is supported by scientific research implicating dysbiosis in the development of acne vulgaris (14, 15).
A healthy microbiota can’t exist in the presence of an unhealthy diet; hence, there’s some overlap between the things the highly skilled researcher Dr. Melnik talks about in his recent paper on acne and the things I’ve talked about in the past regarding the microbiome-acne connection. That said, many other things beside an unhealthy diet can negatively affect microbiome composition.
This leads us over to one of the key messages I want to get across with today’s article…
A healthy diet will only get you so far
Science has left no doubt that diet impacts a variety of processes that play a role in the pathogenesis of acne. Moreover, some recent clinical trials have found that low-glycemic load diets are useful in the treatment of acne vulgaris (8, 9). That said, to date, nobody has investigated whether Paleolithic-type diets are therapeutic for acne sufferers. I find it highly likely that they are. They are probably more therapeutic than typical low-glycemic index diets, seeing as the former exclude all Neolithic foods, as well as fast food, regardless of their glycemic index.
Nevertheless, it should be noted that diet intervention, by itself, is often not enough to bring about completely eradication of acne. Not only that, but some people with acne have undoubtedly found that their skin problems are largely unresponsive to diet changes. This isn’t that surprising, seeing as a healthy diet isn’t a panacea. By itself, it won’t fix a severely damaged microbiota, and it certainly won’t nullify the effects of genetic variations that are detrimental with respects to acne risk.
The fact that acne is virtually nonexistent among people who live in environments that resemble the natural milieu of our Paleolithic ancestors clearly suggests that it’s our environment, and not our genes, that make us sprout lesions. That said, genetics are obviously not inconsequential in the context of acne susceptibility and development. A child who’s genetically susceptible to develop acne, and who also receives a less than ideal mix of bacteria and nutrients from its mother early in life, is particularly bad off and is likely going to find, when he hits adolescence, that his skin stops agreeing with him, perhaps even if he consumes fairly healthy diet.
The bottom line
There is no doubt: Diet and acne are connected. Many of the foods that have entered into the human diet over the past 10.000 years, and in particular the most recent centuries, are problematic with respects to their impact on skin health. Milk and highly processed foods such as chocolate, doughnuts, and cookies are particularly troublesome. It’s long past time that all dermatologists and doctors recognize this fact and that nutritional interventions, as well as various types of microbiome restoration therapies, become a routine part of the treatment of acne vulgaris.