I’ve heard many many links between specific foods causing acne in dermatology clinic (dermatologist approved acne treatment algorithm here). Patients have suggested yogurt, beer, cheese, cereal, chocolate, cinnamon, you name it! My own father swears that when he eats oily Mickey D’s, he gets acne breakouts on his nose. So I was actually pretty excited that we were assigned a journal article earlier in the year looking at the scientific evidence linking certain foods to pimples. Though there’s a lot in the literature, few links are actually solidly based in scientific evidence. Here are the main takeaways:
Glycemic Index / Glycemic Load
Carbs are sugars that are an important source of energy for our body when broken down in glucose. Carb-heavy foods are found in processed foods like pasta, bread, sweets like cookies and candy, table sugar, etc. The glycemic index is basically a measure of rise in blood sugar caused by eating a carbohydrate, and the glycemic load is a measure of carbohydrate content based on what you’re eating. Studies have found that eating a HIGH glycemic index or glycemic load results in MORE acne.
The link between the two is actually well-studied. When you eat high-carb foods, your body releases a hormone called insulin and insulin-like growth factor (IGF-1), which normally helps you process the carbs and turn it into energy storage for the future. Too much IGF-1 however, and a decrease in the proteins that usually bind and deactivate them, causes acne. How? IGF-1 increases skin cell turnover and oil gland and fat production. In addition, insulin and IGF-1 also increase androgens, male hormones that increase oil/sebum production. All this adds to a recipe for MORE acne.
Researchers have assigned groups of study subjects to either low glycemic index diet or normal diet in the gold standard of scientific research, randomized controlled trials. They found that people eating the low carb diets had less number of pimples, and when they looked at this group of people’s skin under the microscope, they found smaller oil glands as well. (One caveat: this study was confounded by weight loss; as the study subjects all lost weight on low carb diets, it is hard to attribute the improvement in acne completely to carbs without considering weight loss as a factor).
What this means for you is that if you struggle with acne, try cutting down on high carb foods, meaning go easy on the sugars and sweeteners, bread, candies, cookies, jams, potatoes, and more. This is definitely not easy (I would have trouble cutting down on carbs! I LOVE noodles more than anything), so I would recommend trying to eat carbs in moderation to help your acne, in addition to the other treatments prescribed by your friendly dermatologist.
Surprising? Well, not really. Milk causes acne the same way that high carbohydrate loads cause acne; they both increase insulin and insulin growth-like factor and production of male hormones (androgens). The surprising thing to me was actually that higher acne was associated with those who drank skim milk and also WHEY protein (found in supplements). Whey protein causes a big spike in insulin production, hence the acne. These patients found that their acne went away after stopping their supplementation.
Other reviews (here and here, just to name two) have looked at the link between acne and various other foods. Unfortunately, we need more modern studies to examine the relationship between these other foods and pimples because the evidence currently isn’t there. Some other foods researchers have looked at include:
- Omega-3 fatty acids – a small study of 5 people (very small!) found that taking Omega-3 fatty acid supplements seemed to have an improvement in inflammatory acne
- Topical and oral antioxidants (vitamins A and E, a catechin found in green tea, flavonoids found in flowers, and resveratrol found in grape skin and red wine, among others) may have beneficial effects on making oil glands smaller in hamsters and have bacteriocidal activity against P. acnes grown in petri dishes. Nothing has been tested on humans.
- Zinc supplementation has been controversial – sometimes it seems to help patients and in other studies, it did not improve acne at all
- Fiber, Iodine, Vitamin A (oral): Inconclusive studies with no clear recommendations
- Chocolate seems to make acne flare in acne-prone teenage boys in a very small study done in 2014, but not reproduced in other studies. No clear conclusion can be drawn.
Overall, the only two things we know for sure so far are that milk and foods high in carbohydrates can trigger and worsen breakouts. What I suggest is if you notice certain foods being linked to bad acne flares for you, try cutting down on those and seeing if you find an improvement in your pimples. I personally feel like I get more acne if I eat oily foods and don’t sleep, so I try to stay well rested and eat healthier (I try!).
Which foods do you find trigger your acne?