Epidemiology is a public health science that informs your understanding of how an exposure such as diet can be related to an outcome like diabetes. A variety of study designs and methods of data collection help address specific questions. Understanding the strengths and limitations of these methods can help you better interpret findings from studies.
Definition of Epidemiology
Epidemiology is the study of the distribution and determinants of disease in populations used to develop appropriate methods for prevention and treatment. Study designs include case control, cohort and randomized controlled trials. Each method has its advantages and disadvantages. The challenge for epidemiologists is to develop the best study design to understand how risk factors such as diet are related to diseases such as diabetes.
Epidemiological Dietary Assessment
Epidemiologists typically use 24-hour food recalls, food frequency questionnaires or food diaries to assess usual dietary intake in studies. Food frequency questionnaires ask people to recall the frequency and amount of foods they typically eat. Twenty-four hour recalls ask people to recall everything they ate the previous day. Food diaries provide the most detailed information, asking participants to write down everything they eat for several days. This last method is burdensome on individuals, making it difficult to use for large populations.
Food Frequency Questionnaires
An example of an epidemiology study that used a food frequency questionnaire was the Health Professionals Follow-up Study, a cohort study of men. In March 2011, an article in "The American Journal of Clinical Nutrition" reported on the relationship between sugar and artificial sweeteners on development of diabetes. The questionnaire used in this study asked participants to report the frequency and amount of beverages they consume that contain either sugar or artificial sweeteners. The questionnaire could not provide an exact estimate of calorie consumption, but it could crudely estimate nutrient intake. The study showed that high-sugar beverage consumption was related to an increased risk for diabetes development.
24-Hour Recalls
A study published in the February 2009 issue of the "Journal of the American Dietetic Association" evaluated the effects of a diet intervention on change in food choices in individuals with diabetes. Using 24-hour recall research can get specific information on which foods individuals are eating. Getting this type of detail is important because the intervention is aimed at getting people to eat less of certain foods and more of others. The study showed that participants in the intervention ate more fruits and nondairy products, which is better for proper diabetes management.
References
- "International Journal of Epidemiology"; Nutritional Epidemiology---Past, Present, Future; Karin B. Michels; 2003
- "The American Journal of Clinical Nutrition"; Sugar-sweetened and Artificially Sweetened Beverage Consumption and Risk of Type 2 Diabetes in Men; L. de Koning, et al.; March 2011
- "Journal of the American Dietetic Association"; Change in Food Choices Following a Glycemic Load Intervention in Adults With Type 2 Diabetes; C.K. Miller, et al.; February 2009
