New research from Spain found that people with prediabetes who ate sardines regularly saw their high risk classification drop from 37% to just 8% in one year.
Oily fish have long been celebrated for their impressive nutritional profile rich in omega-3 fatty acids, calcium, and a host of other essential nutrients. But a newly published study in the journal Clinical Nutrition has zeroed in on one specific fish that may do far more than just round out a balanced diet. Researchers say sardines could play a meaningful role in helping prevent the onset of type 2 diabetes.
What the study looked at
New research from Spain found that people with prediabetes who ate sardines regularly saw their high-risk classification drop from 37% to just 8% in one year. The research was led by scientists, who recruited 152 participants, all of whom had been diagnosed with prediabetes a condition in which blood sugar levels are elevated but not yet high enough to be classified as type 2 diabetes. Each participant was placed on a personalized nutrition plan designed to reduce their risk of progressing to a full diabetes diagnosis.
One group was given an additional instruction: incorporate 200 grams of sardines into their weekly eating routine. That amount works out to roughly two standard cans. Participants were provided with recipes to make the process easier and were advised to eat the fish whole bones included to maximize the nutritional benefits, the results were notable.
At the start of the study, 37% of the sardineeating group were considered high risk for developing type 2 diabetes. After 12 months of following their nutrition plan, that figure had dropped dramatically to just 8%. The comparison group, which did not include sardines in their diet, showed far less improvement starting at 27% high risk and ending the year at 22%.
Beyond the diabetes risk numbers, the sardine group also experienced broader health improvements. Participants saw positive changes in their cholesterol levels, blood pressure, insulin resistance, and even in the hormones responsible for helping the body process sugar more efficiently. Those are the kinds of across the board metabolic improvements that researchers and clinicians tend to pay close attention to.
Why sardines specifically
Why sardines may be the ultimate diabetes prevention food. Part of what makes sardines stand out is how much nutritional value they pack relative to their size and cost. They are a rich source of omega 3 fatty acids, which are known to support cardiovascular health and reduce inflammation. They also contain high levels of calcium particularly when eaten with their bones along with vitamin D, protein, and taurine, an amino acid that has been linked to improved insulin function.
On top of all that, sardines are widely available, budget-friendly, and carry a relatively low environmental footprint compared to many other animal protein sources. The researchers behind the study noted that sardines are both accessible and broadly accepted, making them a realistic recommendation for a wide range of patients not just those with specialized diets or higher food budgets.
How to add them to your diet
Whether reducing diabetes risk is the goal or simply eating more nutrient-dense food, sardines are a surprisingly versatile option. They work well tossed into a salad, spread on whole-grain toast with a squeeze of lemon, or stirred into a pasta dish like puttanesca, where their briny flavor becomes part of a bold, satisfying sauce.
For anyone managing prediabetes or looking to make simple, evidence backed changes to their eating habits, two cans a week appears to be a low effort, high reward place to start. As always, any significant dietary changes are worth discussing with a primary care provider or registered dietitian who can offer guidance tailored to individual health needs.
