Though greasy french fries and chocolate have always seemed to get a bad rap tied to acne, a growing body of dermatology research suggests more specific links between diet and acne – and one of the dietary culprits may be how the foods you eat affect your blood sugar.
When you eat foods containing carbohydrates (sugars and starches), your blood sugar rises. The “glycemic index” of a food refers to the effect the food has on your body’s blood sugar levels. The glycemic index ranks food on a rising scale up to 100 to describe how quickly the carbohydrate in the food is broken down and absorbed into your bloodstream.
With a glycemic index of 70, white bread is often used as an example of a food with a higher glycemic index. The higher the rise in glucose (sugar) in the blood stream, the more insulin is produced to store it. Over time, this can lead to higher insulin levels that can result in inflammation, weight gain and resistance to insulin’s ability to store sugar. Ultimately, it can lead to type 2 diabetes.
How does this affect acne? UW Health integrative dermatologist Apple Bodemer explains that when your blood sugar spikes, it can lead to inflammation, which plays a role in acne. Eating lots of high glycemic index foods can also elevate hormones that increase the activity of oil glands in the skin, which ultimately contributes to the formation of acne.
“Acne is not seen in populations that eat diets with very low glycemic index values,” Bodemer says. “When people switch to low glycemic index diets, we see fewer acne lesions, lower inflammatory markers and smaller oil glands.”
What is considered high and low glycemic index (GI) values?
- High: 70-100
- Medium: 56-69
- Low: 55 or less
Another measuring tool, called “glycemic load,” takes into consideration the amount of carbohydrates in a serving of a particular food. While it can be confusing to look up lots of numbers for everything we eat, Bodemer says there are some simpler, general guidelines to follow if you’re trying to avoid aggravating acne through your diet.
If you’re struggling with acne, what types of foods are good choices?
Whole grains: Whole grain pumpernickel has a GI of 46 (low); a non-whole grain Kaiser roll has a GI of 73 (high).
Beans and legumes:
- Chickpeas: 33 (low)
- Lentils: 29 (low)
Nuts and seeds:
- Most non-starchy vegetables
- Sweet potatoes have a GI of 54 (low). A baked white potato has a GI of 85 (high).
- Apples or pears: 36 (low)
- Peaches: 28 (low)
- Grapefruit: 25 (low)
What foods should be avoided?
Most processed foods:
- Boxed cereal
- Many crackers and rice cakes
- Instant oats
- Sweetened baked goods and candies
- White bread
- White rice
- White potatoes
Other Food and Cooking Tips
- Ripe fruits have a higher glycemic index/load than less ripe fruits.
- Cooking can increase glycemic index/load, so al dente pasta is a better choice than soft pasta (e.g., cooking pasta for slightly less time)
- Combining foods with protein (e.g., beans and nuts) or fat will slow digestion and allow for slower conversion of carbohydrates to blood sugar, which is a good thing when you’re eating to control acne.
Even if you have clear skin, Bodemer says paying attention to the glycemic index and glycemic load of the foods you eat can be helpful in staying healthy. (Glycemic load is another tool that also takes into account the amount of carbohydrate in a serving of a particular food.)
“It is clearly beneficial for the treatment and prevention of diabetes, as well as prevention of cardiovascular disease,” Bodemer says. “It may also help with weight loss and obesity prevention.”
Learn more from UW Health Integrative Medicine: Glycemic Index and Glycemic Load