Oily fish has long been known as a source of important nutrients. Spanish researchers have now discovered that adding sardines to a healthy diet helps reduce the risk of diabetes, and perhaps even slows its progression.

Oily fish contains omega-3 polyunsaturated fatty acids, with proven cardiometabolic benefits. Sardines in particular prove important for our diet: these fish are not only rich in omega-3, but also vitamins B (B3, B5, B12), D and E, selenium, calcium, phosphorus, and taurine (an amino acid).

Spanish researchers at the Universitat Oberta de Catalunya investigated to what extent the combined effect of these nutrients can contribute to a beneficial effect on diabetes.

The team recruited seniors diagnosed with prediabetes — characterized by fasting blood glucose between 1 and 1.25 g/l (100 and 125 mg/dL). Without even considering the lifestyle (and especially the dietary habits) of the participants, the risk of diabetes is already quite high.

The researchers drew up a nutrition program and followed the participants for a year. The dietary requirements were uniform, with the one difference: half had to consume 200 grams of sardines per week. Metabolic variables were recorded before and after follow-up.

The main focus was on people at very high risk of developing diabetes. Before the start of the study, they represented just over a third (37%) of the sardine group; by the end of the program, this share had fallen to 8%.

In the other group, that percentage fell from 27% to 22% over the same period of time. Other parameters also improved much more clearly in the sardine group, such as “good” (HDL) cholesterol, triglycerides, insulin resistance, and blood pressure.

After blood tests for metabolites, the researchers attribute this beneficial effect directly to the nutrients of sardines, including omega-3, vitamin D, and taurine. “We can conclude that an adapted diet with sardine supplements has a real protective effect against the development of type 2 diabetes and in the prevention of cardiovascular disease,” the researchers reported afterward.

Please note that adding sardines to the diet is only useful if the general diet is also healthy and balanced, with an abundance of fruits and vegetables as a priority and a restriction on the consumption of red or processed meat, products with a high content of (saturated) fats and added sugars.

Steven Peck

Working as an editor for the Scientific Origin, Steven is a meticulous professional who strives for excellence and user satisfaction. He is highly passionate about technology, having himself gained a bachelor's degree from the University of South Florida in Information Technology. He covers a wide range of subjects for our magazine.