Concept explainers
Association between Glycemic Load and Acne? An article in the Journal of the Academy of Nutrition and Dietetics reported on a study of diet in subjects with moderate to severe acne. Read the excerpts from the abstract and answer the questions that follow. (Source: Burris et al., “Differences in dietary glycemic load and hormones in New York City adults with no or moderate/severe acne,” Journal of the Academy of Nutrition and Dietetics, vol. 117 [September 2017]: 1375-1383)
Methods: Sixtyfour participants (no acne,
Results: Participants with moderate/severe acne consumed greater total carbohydrate compared to participants without acne. Participants with moderate/severe acne had greater insulin compared to participants without acne. Although there were no differences between groups, 61% of participants reported foodinfluenced acne.
a. Was this a controlled experiment or an observational study? Explain how you know.
b. Assuming the study was properly conducted, can we conclude that higher consumption of carbohydrates causes more severe acne? Explain.
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