Previous studies have highlighted the link between the intake of certain foods containing omega-3 fatty acids and the incidence of diabetes. It has been found that consumption of long-chain fatty acids like omega-3 may increase the incidence of diabetes. In this study, the authors sought to investigate the relationship between the levels of fatty acids present in blood and the risk of diabetes. The blood levels of these specific fatty acids were analyzed in 3,088 old men and women with an average age of 75 years. As a follow-up to this study, the relative risk of diabetes was assessed in all these individuals. It was found that the levels of omega-3 fatty acids were not directly related to the increased incidence of diabetes.
Type-2 diabetes is highly prevalent in the United States, with a 27-53% lifetime risk of acquiring it since birth. The occurrence of diabetes along with heart diseases can be minimized through well-managed diets and physical activities. Various long-chain fatty acids such as eicosapentaenoic acid, docosahexaenoic acid, and alpha-linolenic acid have cardiac benefits, and their consumption leads to decrease in the incidence of heart diseases. However, there have been inconsistent reports that these fatty acids increase the incidence of diabetes. These reports were based on studies that were performed using questionnaires that were filled by the patients rather than clinical quantification of sugar and fatty acid levels. In order to find out whether there was any association between fatty acids and the risk of diabetes, this study focused on quantifying the levels of fatty acids in an older population and correlating them with the incidence of diabetes.
- The participants in this study were from the Cardiovascular Health Study (CHS). The study included 5,201 individuals more than 65 years old. Out of these, only 3,088 individuals who fulfilled the experimental criteria were chosen.
- An estimation of the fatty acid content for each individual was performed using blood samples collected in 1992-1993.
- The blood sugar levels were assessed periodically over a period of ten years for all the participants.
- The levels of risk factors for diabetes were then estimated and analyzed statistically.
- The incidence of diabetes in the studied population was found to be about 204 cases after a period of nearly 10 years.
- The levels of eicosapentaenoic acid and docosahexaenoic acid in the blood were not associated with an increased risk of diabetes. In fact, it was found that those with higher levels of these had a lower risk of diabetes.
- Similarly, there was no risk of diabetes in those with high levels of alpha-linolenic acids in their blood.
The levels of fatty acids were measured only once in this study. The change in the levels of fatty acids over a longer period was not assessed. The incidence of diabetes in the studied population was limited and a modest comparison was not feasible. With most of the participants being older individuals and Caucasians, the results of this study cannot be generalized.
The results of this study were contrary to those obtained from questionnaire-based studies. It was found that the fatty acid levels in blood were not associated with higher incidences of diabetes. Those with high concentration of eicosapentaenoic acid, docosahexaenoic acid, and alpha-linolenic acid had a lower risk of diabetes. These negative associations imply that these fatty acids could in fact be beneficial in reducing the risk of diabetes. The supposed rise in the incidence of diabetes due to fish consumption was also disproved by this study. The authors suggest that compounds other than the fatty acids in fish may have induced higher incidences of diabetes that were recorded in previous studies.
For More Information:
Plasma Omega-3 Fatty Acids and Incident Diabetes in Older Adults
Publication Journal: American Journal of Clinical Nutrition, May 2011
By Luc Djoussé; Mary L Biggs
From the Harvard Medical School, Boston, Massachusetts and University of Washington, Seattle, Washington
*FYI Living Lab Reports Are Summaries of the Original Research.