Findings demonstrate independent associations between HbA1c concentration across the normal range of HbA1c and both total fat intake and the pattern of dietary fat intake. The amount of fat you eat can affect your A1C level, say researchers in the United Kingdom, but the type of fat can also make a difference. Researchers writing in the November 2001 issue of Diabetes Care report that people who consumed more polyunsaturated fat, which includes most vegetable oils, nuts and high-fat fish, had lower A1C levels across the normal range than those whose fat intake came primarily from meat, milk and milk products.
OBJECTIVE—To describe the relationship between total dietary fat and the pattern of fat intake and HbA1c.
RESEARCH DESIGN AND METHODS—In this cross-sectional study, 2,759 men and 3,464 women (40–78 years of age) without a previous diagnosis of type 2 diabetes were recruited from a population-based sampling frame. Diet was assessed using a self-reported semi-quantitative food frequency questionnaire.
RESULTS—The HbA1c level was negatively associated with the polyunsaturated fat–to–saturated fat ratio (P:S ratio) of the diet (ß = -0.0338 HbA1c% per SD change in P:S ratio; P < 0.001) and positively associated with the total level of fat intake (ß = 0.0620 HbA1c% per SD change in total fat intake; P < 0.001), adjusted for age and total energy intake. The associations remained significant when adjusted for each other and for total energy, protein, age, sex, family history of diabetes, BMI, waist-to-hip ratio, physical activity, and smoking (for P:S ratio, ß = -0.0200 HbA1c% per SD change in P:S ratio, P = 0.013; for total fat, ß = 0.420% HbA1c% per SD change in total fat intake, P < 0.001). The benefits from a high P:S ratio were attributed to a lower saturated fat intake.
CONCLUSIONS— Those who consumed more fat also had higher A1C levels across the normal range when adjusted for age, total energy intake, protein intake, age, sex, family history of diabetes, weight, waist-to-hip ratio, physical activity and smoking. Those who had a higher ratio of polyunsaturated fat to saturated fat had lower A1Cs, which researchers attribute to lower overall saturated fat intake.
These findings demonstrate independent associations between HbA1c concentration across the normal range of HbA1c and both total fat intake and the pattern of dietary fat intake. They provide further support to efforts promoting modifications in the intake of dietary fat. Diabetes Care 24:1911-1916, 2001