While cardiovascular and other health benefits of unsaturated fats in oily fish are well established, and these fats are key to the highly recommended Mediterranean diet, there has been little specification about the type of fish and the preventive mechanism involved in its health claim. The sardine is a source of omega-3 and taurine that, in isolation or in synergy, may delay type 2 diabetes (T2D) through different molecular mechanism. This spring, the Clinical Nutrition journal published the results of a Spanish randomized study investigating the possibility of preventing T2D in older people with pre-diabetes by enriching their diets with sardines.
The researchers enrolled 152 patients aged 65 and older who had been diagnosed with prediabetes (blood glucose levels between 100-124 mg/dL) and placed them all on a nutritional program to reduce the risk of diabetes for 1 year. In addition, about half (n = 75) were also instructed to consume 200 g of canned sardines in olive oil per week, in 100 g servings consumed twice per week. Those participants were recommended to consume the entire sardine, without removal of bones, due to their rich content of calcium and vitamin D. They were also provided with recipes that used canned sardines.
At the end of our 1-year study, the rate of new-onset T2D was 2.7% and 5.2% in the sardine group and control group, respectively. The percentage of participants classified as being at a very high risk of type 2 diabetes, assessed by the Finnish Diabetes Risk Score (FINDRISC), compared with baseline, had declined to a much greater degree in the sardine consumption group (37% at baseline vs 8% at 1 year) compared with those in the control group, who only consumed the nutritional diet (27% vs 22%) (P = .021). In addition, those in the sardine group had greater increases in healthy HDL cholesterol and the glucose-regulating protein hormone adiponectin, with decreases in triglycerides compared with the nonsardine group (all P < .005). Furthermore, the sardine consumption group had a greater decrease in insulin resistance, assessed by Homeostatic Model Assessment for Insulin Resistance (HOMA-IR; P = .032). Those in the sardine group also showed significant decreases in systolic blood pressure (P = .014) and diastolic blood pressure (P = .020) versus baseline, while no significant changes were observed in the control group.
The authors conclude that canned sardines are not only reasonably priced and easy to find, but they have also a greater protective effect against developing T2D and help to control other cardiovascular risk factors.
Reference: https://www.clinicalnutritionjournal.com/article/S0261-5614(21)00153-9/fulltext
