Feedback—Your FAQs Answered

What connection is there between a high GI diet and acne?
The jury is still out on the acne diet link. But the debate is ongoing. After Prof Loren Cordain and his colleagues published ‘Acne Vulgaris: A Disease of Western Civilization,’ Archives of Dermatology/Vol 138, December 2002) we have received a number of questions asking where you can read more about GI and acne.

In Cordain’s article, he and his colleagues note the complete absence of acne among the non-westernized Kitavan Islanders living on the Trobriand Islands near Papua New Guinea and the Aché hunter-gatherers of Paraguay. According to Cordain, the perfect skin could not be explained just by genetic factors, but likely was the result of differing environmental factors including diet. The Kitavan diet consists mainly of fruit, fish and tubers and is virtually uninfluenced by Western foods. The Aché diet includes wild (game) and foraged foods, locally cultivated foods (peanuts, maize, rice and sweet manioc, a native root) and a small percentage of Western foods (pasta, flour, sugar, tea and bread).

Cordain believes the Western diet filled with refined carbs permanently boosts the production of the hormone insulin, which leads to acne. By elevating growth factors and hormones, insulin indirectly stimulates the overproduction of oil and skin cells in pores. Clogged pores nourish bacteria, forming infected blemishes.

Follow up research on GI and acne is underway but nothing has yet been published. However, you can read Cordain’s article in full on (PDF, 108 kB).

I have been reading What Would Jesus Eat? Would this be a low GI diet?
Our best guess is yes. People living in the Middle East 2000 years ago would have eaten a healthy Mediterranean-style diet that fits naturally into the low GI way of eating with lots of low GI carbohydrates including fruit, vegetables, legumes and cereal grains, plus nuts, plenty of fish and some lean meat. They certainly would have used olive oil in their cooking and their bread (a staple) would certainly not have been made with highly refined flour. Research since the 1980s reveals that a traditional Mediterranean-style diet can lower cholesterol and blood pressure and, therefore, the risk of heart disease. Experts think it is healthy not only because it’s lower in saturated fat and higher in monounsaturated fats, but also because it’s rich in low GI carbohydrates and micronutrients (such as folate) that reduce the risk of heart disease. As long as total fat intake isn’t too high (that is, no more than 30 to 35 percent of total kilojoules/calories), everyone—including people with diabetes—is likely to benefit from a healthy low GI Mediterranean-style diet.