Acne and Nutrition – Myths, Facts and the Glycemic Index
As a physician, I was taught that acne and nutrition weren’t as directly connected as previously believed. The medical myths about certain foods — like chocolate — causing acne have been previously disproven. Consequently, most of my advice about acne is based around skin hygiene and treatments with creams or medications. But now, that will change. It seems dietary habits do affect acne.
A study from the Royal Melbourne Hospital in Australia took a closer look at improving acne by changing dietary habits. In the articles published in the Journal of the American Academy of Dermatology and the American Journal of Clinical Nutrition, researchers found a decrease in the number of acne spots in individuals who ate a diet of low glycemic load foods.
The study was prospective and divided a group of 43 young men (aged 15-25) into two groups: one group that ate a typical diet with high glycemic load foods and the experimental group that was educated on how to follow a diet of higher protein foods and foods lower in glycemic load like fruits, vegetables, whole grains, and beans. After 12 weeks on each diet, the group that ate the lower glycemic load diet had a significantly lower number of acne spots, decreased fasting insulin, and a reduction in weight, BMI, fat percentage, and waist circumference when compared with the group that continued a normal diet.
The scientists that performed the study felt that foods high in carbohydrates and simple sugar, which raise blood sugar and insulin levels, increase the formation and severity of acne. It seems acne may be associated with French fries, white bread, soda pop, and other high glycemic load snacks.
What Is Glycemic Load?
Glycemic load is calculated from both a food’s glycemic index and its total carbohydrate content. Glycemic index is a concept that was developed to help diabetics understand the food that they were eating. A food’s glycemic index is a relative scale that compares the effect of foods on blood sugar levels. Some foods (with high glycemic index numbers) raise blood sugar quickly, while others (with lower numbers) cause a slower rise after eating. Foods with the same number of calories may have a very different effect on blood sugar and therefore a different glycemic index. The glycemic index is typically based on glucose, a simple sugar. Raw glucose has a glycemic index of 100 and represents the highest glycemic index value. For example, white bread has a high glycemic index above 70, while whole wheat bread has a glycemic index around 52. Typically, foods with more fiber content have lower glycemic indices. The fiber slows the absorption of the sugars and carbohydrates in the food and keeps the blood sugar from shooting too high.
The glycemic index scale does not consider the total caloric content of a food. Glycemic index is only part of the whole effect of food on blood sugar. This is why researchers created the concept of glycemic load. Glycemic load not only considers how fast the food raises sugar, but how much total sugar/carbohydrates are in the food. By dividing a food’s glycemic index number by 100 and multiplying that number by the available carbohydrate content (carbohydrates minus fiber) in grams, you can calculate a food’s glycemic load.
Cola, which has a glycemic index of 50 to 60, has a high glycemic load due to its large amount of available carbohydrate calories. However, while watermelon has a relatively high glycemic index (over 70) because it rapidly increases blood sugar, it has a high fiber content and low total carbohydrate content (low calories), it has a low glycemic load. So event though watermelon raises the blood sugar fast, it doesn’t really have much carbohydrate to change into sugar, so the rise doesn’t last too long.
I don’t expect you to calculate glycemic load for every food you eat. I surely don’t. There are lists on the internet that give the glycemic indices and glycemic loads for many foods. But the important concept is to choose foods that are high in nutrition, high in fiber, and low in calories. This is the beauty of the SuperFoods. Choose whole grain foods, fruits, vegetables, and high protein foods like turkey and fish. Avoid processed, low nutrient, and high calorie foods that have high glycemic loads. The benefits will be more than just an improvement in acne.