Ask A Dermatologist: The Link Between Diet and Acne
Acne is one of the most common skin conditions affecting roughly 80% of all individuals in their lifetime, to some degree. Acne is caused by sebum (oil in your skin), dead skin cells, bacteria (i.e., Cutibacterium acnes— formerly known as Propionibacterium acnes) and other impurities clogging pores which can lead to blackheads, whiteheads and inflammation (papules, pustules and cysts). There is increasing evidence that certain foods may contribute to inflammation and sebum production, which can make acne worse. Here’s what the science says about which foods cause acne, and which foods might help you maintain clear skin.
Foods that Potentially Cause Acne
There is increasing research investigating the link between diet and acne. Certain foods that increase internal inflammation, or contain higher levels of hormones, sugars and even proteins, may have a higher association with triggering acne breakouts. The current research attempting to correlate diet with acne flares has primarily included the following:
Refined Carbohydrates and Sugars: Foods rich in refined carbohydrates (think breads/pastas containing white flour, rice cakes, most crackers, chips/fries, sugary drinks and sodas) have been shown to increase acne in some individuals. These foods are considered to be “high glycemic index” foods that can quickly raise blood sugar levels which ultimately causes increased inflammation which may negatively impact the skin, leading to more acne.
Cow’s Milk: Whether skim, low-fat or regular, there is some evidence that individuals consuming more milk tended to have more frequent breakouts. Studies have not shown this connection with yogurt or cheese. Whey and casein, two proteins in milk, may cause elevated blood sugar which leads to inflammation. In general, it remains a mystery as to why cow’s milk may cause acne to flare. In the U.S., some milk products may also contain various hormones that can contribute to inflammation.
Omega-6 Fats: You may have heard there’s ‘bad fat’ and ‘good fat.’ Good fat (or Omega-3) can be found in nuts, avocados and fish. Bad fat (or Omega-6) is found in fast foods, corn and soy oils, especially in processed and packaged foods. In addition to high amounts of refined carbs and sugars, “Western diets” also have increased levels of Omega-6 fats, which may lead to increased inflammation and hence acne.
Low Glycemic Diet for Minimizing Acne
Foods that cause elevated blood sugars cause increased insulin levels, which may lead to the downstream effects causing acne. Low-glycemic foods are ones that don’t cause your blood sugar (or subsequently insulin levels) to spike after a meal. A Low-Glycemic Index diet helps to reduce the body’s inflammatory response to insulin. This is important because there is evidence that elevated insulin can result in excess sebum production. Basic foods that are low-glycemic are low in sugars and include the following:
- Nuts, avocados, eggs and other healthy fats (e.g., Omega-3)
- Fish, poultry, meat and other foods high in protein
- Dark, leafy greens and rich colorful vegetables
“Moderate glycemic foods” are broken down more slowly than high glycemic foods causing a slower and more gradual rise in blood sugar levels over time. Examples of moderate glycemic foods include minimally processed whole grains and corn, white rice, couscous, white and sweet potatoes and fruits.
Studies investigating the connection between low-glycemic diets and acne have revealed the following:
- One study comparing those with severe acne to those with none found patients with acne had a significantly higher glycemic load than patients without.
- A weight loss study involving over 2,200 women inadvertently found 87% of those placed on a low-glycemic diet reported fewer breakouts.
- In a randomized controlled trial patients who followed a low-glycemic diet for 12 weeks not only lost weight but experienced clearer skin. The control group showed no change in skin condition or body weight.
Foods to Eat for Clearer Skin
While a low-glycemic, dairy-free diet may help your complexion, there could be other foods you’re sensitive to that are causing your breakouts. One way to track the effect of your diet and how foods affect you is to keep a food diary.
- Write down what you eat when you eat it
- Make a note on the state of your skin (breakouts, dry, oily, etc.)
- If you begin to see patterns, eliminate the foods you seem sensitive to
- Track what happens after one week up to 6 weeks without that particular food or foods
Everyone’s skin type is different, as is their reaction to food. Chocolate, for example, may be a trigger for one person but not for another even though there isn’t much data supporting this causation.
The Verdict on Food and Acne
While there are many studies that appear to show a connection between diet and acne, there’s still more work to be done before any one food is labeled ‘bad’ or ‘good’. The American Academy of Dermatology does not recommend specific dietary changes for people with acne as the data is overall insufficient at this time. Many of the studies available for review rely on dietary records which may be lacking complete information or even bias. There are other things that trigger acne, i.e., hormone imbalances, medications, environmental exposures, stress, etc., which may not be accounted for in some (or most) of these studies. These studies cannot overtly explain a causation between diet and acne, but do try to explain whether there is an increased or decreased association between the two. In general, reducing systemic inflammation as the most promising means of keeping your acne under control. This includes:
- Eat whole, low-glycemic foods
- Practice stress reduction techniques
- Stay hydrated
- Avoid processed or packaged foods
As we continue to gather data, these guidelines may become more concrete. Having a healthy diet and lifestyle can help lower inflammation, so for best results, balance these methods with an acne-aware skincare routine to prevent and treat breakouts. Like with rosacea, if you feel that certain foods trigger a flare, do your best to avoid them and talk to your dermatologist about your concerns.