What Causes Acne? New Findings will Amaze you!

By Kim Crawford, M.D. Last updated: September 6, 2018
foods that cause acne

Well-accepted Causes of Acne

Acne affects between 40 and 50 million adolescents and adults in the United States alone! We know the big factors causing our breakouts such as excess sebum production, clogged pores, and (probably) the bacteria Propionibacterium acnes all contribute to the pathogenesis of acne. We also know factors such as cigarette smoking, air pollution, skincare, makeup and hair products, some medications, and stress (high cortisol) play a role in the causation of acne. This article will explore the causes of acne you may not know. 

Over the last several decades, the dermatology literature is filled with studies (mostly not-too-well-done IMHO) concluding there is no direct association between diet and acne. Although the debate rages on, I’ve seen enough evidence, both in the literature and in my clinical experience, to conclude that there is, in fact, a link. This discussion will include the following:

  • The link between diet and acne
  • Blood sugar and acne
  • Inflammation and acne
  • Leaky gut, intestinal dysbiosis, and acne
  • Hormones and acne

Are There Foods that cause Acne?

In a word—yes! The strongest evidence to date on dietary triggers for acne is for high-glycemic-load diets. In a randomized controlled clinical trial, acne patients demonstrated significant improvement after 12 weeks of a low-glycemic-load diet.

Subsequent studies documented this way of eating (basically an anti-inflammatory diet) resulted in lower androgen bioavailability and reduced skin sebum production. In another similarly randomized study, a 10-week low-glycemic-load diet improved acne, and skin biopsy sample examination revealed decreased skin inflammation and reduced sebaceous gland size. This has prompted me to emphasize to all patients with acne that “eating for health” (low sugar, low starch, no fast foods, low processed foods) will help to clear up their skin!

foods that cause acneFurthermore, some studies have demonstrated an association between acne and dairy consumption; especially in adolescence. Some epidemiological studies link low glycemic diets where milk products are not consumed to a near-absence of acne. So, I recommend removing dairy products from your diet; you can certainly get the nutrients elsewhere.

Lastly, the concept of IgG food sensitivities is slowly evolving; with only a recent nod to their existence by “conventional medicine.” We know that food sensitivities can cause skin rashes, and they might even cause acne in some people. Therefore, if you notice a particular food seems to be causing acne for you, try eliminating that food.

One final word about chocolate; long blamed for acne breakouts. If you have a food sensitivity as described above, it might give you acne. Also, if you eat a lot of high-sugar milk chocolate products, it will likely aggravate your acne breakouts based on its high glycemic load.

If you are not one of the rare people with a food sensitivity to chocolate, there is no reason you cannot enjoy 3-5 squares of 75-90 percent dark chocolate each day.

Does controlling your Blood Sugar Tame Acne? 

We all know that the incidence of obesity and therefore the incidence of pre-diabetes and diabetes is steadily increasing in the U.S. and  worldwide as well. The question of what exactly is a normal blood sugar is being debated, but it is clear that chronically high blood sugar will prematurely age the skin.

To equate having a high blood sugar with acne, we have to make some assumptions. First of all, there is a link between obesity (which causes inflammation and then acne) and blood sugar levels. Next, there is a link between high-glycemic diets and both obesity and blood sugar levels. Although no formal connection has been proposed, it seems evident there is a link between high blood sugar and acne. One extensive study shows that a low-glycemic load diet which is full of fibrous vegetables and low in processed foods will improve insulin resistance (which lowers blood sugar) and improves acne.

Reduce Systemic Inflammation to Decrease Breakouts

The Main Causes of chronic inflammation
Toxic diets

Inflammatory foods include sugary foods, highly-processed carbohydrates, high-industrial (seed oil) fat, high-gluten, and, most fast foods. Further, this eating pattern also causes oxidative stress which in turn worsens inflammation.


Your overall levels of Inflammation risk are much higher if you are obese or overweight. Overweight or obese men and women have more inflammatory markers such as CRP, insulin, and inflammatory cytokines than men and women of the same age who are not obese or overweight; in many clinical studies. Furthermore, inflammation levels drop when men and women lose body fat.

Excessive omega-6 intake

Omega-6 fats are the predominant fats in dairy and meat which is not proven to be a risk factor for acne but beware the possibility. Omega-6 fatty acids form the precursors for inflammatory eicosanoids, which are an integral part of the entire inflammatory response.

Insufficient Omega-3 intake

Above all, it is about your ratio. On the flip side of the omega-6 fat function, we find the omega-3 fatty acids. Omega-3 fats form the precursors for anti-inflammatory eicosanoids. Poor omega-3 levels mean the insufficient production of anti-inflammatory eicosanoids, with a resulting lopsided inflammatory response to normal stimuli.


Overtraining (working out with inadequate recovery) can cause chronic inflammation. Inflammatory markers and sophisticated athletic inflammatory markers can detect if someone is overdoing it. Elite athletes should use these laboratory testing tools to optimize their performance.


Heavy metals, biotoxins such as mold toxins, Lyme toxins and more can cause chronic inflammation.

Lack of sleep

Poor sleep is a widespread problem in the U.S. We go to bed too late, wake up too early, and don’t sleep long enough. We likely use too many electronics late at night and disrupt the quality of what little sleep we get as well. Believe it or not, our chronic insomnia can contribute to our chronic inflammation.

What to do? 

For optimal health, get the inflammation under control. It is necessary to achieve an ideal weight, eat an anti-inflammatory diet, exercise appropriately, and get enough sleep. There is a paucity of research looking solely at the role of inflammation and acne vis-a-vis supplementation, but enough on some specific items which bear mentioning.

Omega-3 fatty acids warrant further study regarding their role in acne control. In one 10-week clinical trial, omega-3 fatty acid supplementation resulted in clinical and biopsy (histopathological) improvement in acne lesions.

Zinc has been studied in several randomized clinical trials as well. Many studies show that zinc is particularly anti-inflammatory for those with acne. Various forms of zinc have been studied, including zinc gluconate, zinc sulphate, and methionine-bound zinc, amongst others.

As a postscript, note that cigarette smoking, exposure to pollution, poor oral health and excessive alcohol consumption can lead to chronic inflammation. Lastly, poor “gut health” not only leads to inflammation but now we know it also directly leads to acne.

Altered Gut Function Impacts the Skin

In the last few years, low stomach acid (hypochlorhydria) has been confirmed as a significant risk factor for small intestinal bacterial overgrowth (SIBO), which can, in turn, cause increased intestinal permeability (“leaky gut“), leading to systemic inflammation. Further, systemic inflammation leads to acne, but that’s not the end of the story.

Many studies suggest that intestinal permeability might be augmented in those with acne. However, only a few researchers have investigated the intestinal microbiome in acne patients. Russian investigators who studied 114 patients with acne vulgaris noted that 54% of acne patients have “unhealthy” differences in their intestinal flora. The results also suggest that gut bacteria in those with acne vulgaris may very well enhance the presence of circulating endotoxins (toxic bacterial by-products leaked through the gut) in the blood of those acne patients compared to healthy controls.

Although the mechanisms for how the gut and skin communicate are not well understood, acne patients seem to have some skin-gut connection that likely involves abnormal intestinal bacteria and increased gut permeability.

Additionally, in studies where acne patients with dysbiosis in their intestinal flora received probiotics, there was a reduction in the duration of acne treatment needed to achieve skin clearing. While the mechanism of how probiotics help is not clear, recent research shows they may reduce oxidative stress and inflammation in acne patients. The ability of probiotics to reduce systemic oxidative stress, regulate inflammatory cytokines, and reduce other inflammatory markers may all contribute to their positive effects on acne. Overall, studies suggest the gut microbiome may play an important role in acne pathogenesis.

In short, treat SIBO with herbals (referenced above) and take probiotics to replace the “bad” bacteria and balance your microbiome.


In our skin, sebaceous glands are the main sites of hormone biosynthesis; especially androgens. The effect of dihydrotestosterone (DHT) on sebocytes is well confirmed. Further scientific evidence supports the interplay between androgens, insulin, insulin-like growth factor, and a hyperglycemic diet in the pathogenesis of acne.

Androgens not only regulate sebum synthesis in sebocytes but also increase inflammation in acne. Genetic studies reveal that the regulation of the androgens receptor is an important factor in severe acne. In fact, this is the basis for recommendations for DHT blockers and the current research on topical anti-androgens for the treatment of acne. Presently, some Dermatologists recommend the use of ketoconazole (Nizoral) to block DHT topically. This has also been found to be a remedy for treating fungal infections which can complicate acne; another topic altogether.

In conclusion, the current state of the art for acne treatment is here. And I’d be remiss if I didn’t mention the best way to cleanse acned skin which can be found here.

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