The epidemic of obesity and the resulting development of type 2 diabetes is occurring throughout the world. Some research suggests that not only does the amount of fat consumed contribute to the problem, but also the type of dietary fat. Other studies have not found an association between the type of dietary fat and obesity or type 2 diabetes. However, most existing studies have not evaluated the impact of dietary patterns, and therefore may not be capturing the impact of the combinations of foods and fat type on these diseases. Brayner and colleagues conducted a study using a dietary pattern approach to determine if the type of dietary fat influences obesity and type 2 diabetes. The type of dietary fat studied were saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA). They report their results in a paper published in the November 2021 issue of The Journal of Nutrition.
Data were derived from subjects in the UK Biobank study and included two or more 24-hour dietary assessments and self-reported incidence of type 2 diabetes. Reduced rank regression was performed to determine if the dietary intake pattern for SFAs, MUFAs, and PUFAs (% of energy intake) were associated with obesity, abdominal obesity, and type 2 diabetes.
Two distinct dietary patterns were identified. Dietary pattern 1 was positively correlated with SFAs, MUFAs and PUFAs (higher intakes of nuts, seeds, and butter, with lower intake of fruit and low-fat yogurt). Dietary pattern 2 was positively correlated with SFAs and negatively with PUFAs and MUFAs (higher intakes of butter and high-fat cheese, and lower intake of nuts and seeds). Dietary pattern 1 was not associated with obesity or type 2 diabetes, whereas dietary pattern 2 was associated with obesity and abdominal obesity but not type 2 diabetes. These observations led the authors to conclude that a dietary pattern with higher SFA and lower PUFA foods was associated with obesity and abdominal obesity.
In an editorial, Frankenfeld provides a detailed explanation of the various approaches used to classify dietary patterns and the benefits of utilizing the reduced rank regression approach. Frankenfeld suggests the lack of association between dietary pattern for type of fat and type 2 diabetes may be due to the interactions of dietary fat with other nutrients that influence type 2 diabetes risk. Further work is recommended to confirm the role of type of fat in obesity development.
Barbara Brayner, Gunveen Kaur, Michelle A Keske, Aurora Perez-Cornago, Carmen Piernas, Katherine M Livingstone, Dietary Patterns Characterized by Fat Type in Association with Obesity and Type 2 Diabetes: A Longitudinal Study of UK Biobank Participants, The Journal of Nutrition, Volume 151, Issue 11, November 2021, Pages 3570–3578, https://doi.org/10.1093/jn/nxab275.
Cara L Frankenfeld, Reduced Rank Regression: Illustration of an Important Tool in the Evaluation of Dietary Patterns and Chronic Disease Risk, The Journal of Nutrition, Volume 151, Issue 11, November 2021, Pages 3269–3270, https://doi.org/10.1093/jn/nxab331.
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