Regular Sardine Consumption May Help Prediabetics Avoid Developing Diabetes

Eating fish can provide many health benefits. The omega-3 fatty acids they contain promote brain and heart health, may prevent arthritis-related inflammation, and may even reduce the risk of depression. A new study from Spain finds that a certain fish could also play a role in preventing type 2 diabetes.

A team led by researchers from the Universitat Oberta de Catalunya and the August Pi i Sunyer Biomedical Research Institute looked at the link between sardine consumption and the risk of type 2 diabetes. They found that regularly eating sardines helped prevent the onset of the illness. The study was published in the journal Clinical Nutrition.


Diana Diaz Rizzolo, study leader and researcher at the Universitat Oberta de Catalunya, says, “Not only are sardines reasonably priced and easy to find, but they are safe and help to prevent the onset of type 2 diabetes. This is a huge scientific discovery. It is easy to recommend this food during medical check-ups, and it is widely accepted by the population.”

To conduct the study, researchers had 152 prediabetes patients aged 65 and older take part in a nutritional program aimed at preventing the development of type 2 diabetes. The intervention group ate an added two cans of sardines in olive oil every week. Researchers encouraged this group to eat the sardines whole, including the bones, because doing so provides extra calcium and vitamin D.

At the beginning of the study, 27% of the non-sardine group were considered at high risk of developing diabetes. After a year, that was down to 22%. Meanwhile, to begin the study, 37% of the sardine group were at high risk. A year in, that was down to 8%. In addition, the second group had a reduced insulin resistance index, increased good cholesterol, increased hormones that accelerate the breakdown of glucose, decreased triglycerides, and lower blood pressure.


Study authors say the lower diabetes risk could be helped by the high-density nutrient nature of sardines. They’re packed with taurine, omega 3, calcium, and vitamin D. Those nutrients taken by themselves don’t necessarily have the same preventative benefits.

Rizzolo explains, “Nutrients can play an essential role in the prevention and treatment of many different pathologies, but their effect is usually caused by the synergy that exists between them and the food that they are contained in. Sardines will therefore have a protective element because they are rich in the aforementioned nutrients, whereas nutrients taken in isolation in the form of supplements won’t work to the same extent.”

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Though the study was limited to older people, the team believes the findings may also be beneficial for other populations.

Rizzolo says, “As we get older, restrictive diets (in terms of calories or food groups) can help to prevent the onset of diabetes. However, the cost-benefit ratio is not always positive, as we found in other studies. However, the results lead us to believe that we could obtain an equally significant preventive effect in the younger population.”


The team has now moved onto studying the effect sardines have on the intestinal microbiota because they want to see if that may also be linked the reduced risk of developing diabetes.

The CDC says that lean proteins like fish can help prediabetics avoid progressing to type 2, along with consuming things like non-starchy vegetables and choosing water over sweetened drinks.

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