Consuming dairy products—cheese in particular—could actually help reduce the risk of diabetes in the American population, according to a study published in the Journal of Nutrition.

For years, U.S. guidelines have recommended two to three servings of dairy per day for American adolescents and adults—a standard that doesn’t change for diabetes patients. But in a world where diabetes affects one in 11 people globally, and plagues U.S. populations in exceedingly high rates, lead study author Paul F. Jacques, DSc, and colleagues questioned whether dairy intake was related to incident prediabetes and diabetes.

“Many individuals may perceive dairy products as health foods, particularly reduced-fat products such as skim milk and low-fat yogurt,” the authors wrote. “For some, certain dairy products may be an important source of protein and several shortfall nutrients ... they may also be a source of potentially harmful saturated fats.”

Jacques and his team designed a study of 2,809 patients and tracked the individuals’ dairy consumption and risk of diabetes over 12 years. Of the nearly 3,000 subjects studied, 1,867 patients were prediabetes-free at baseline. The researchers assessed dairy intake through four or more food-frequency questionnaires, they wrote, and used proportional hazards models and spline regressions to assess their results.

Jacques said most similar studies don’t include initially diabetic patients, but he thought a variety of metabolic status in patients could yield some new, comprehensive results.

“We felt that some of the studies may have a larger proportion of participants with prediabetes and that different types of dairy, based on fat content, fermentation products and/or pre- or probiotic potential, may have differential effects in metabolically healthy individuals and those with prediabetes,” he told Cardiovascular Business.

Of the initially diabetes-free patients, 48 percent had developed prediabetes by the end of the study. The greater study population was a majority overweight or obese before the study, but results showed that total, low-fat and high-fat dairy consumptions were all associated with lower risk of incident prediabetes. Consumption of all dairy products resulted in a 39 percent decrease in prediabetes risk, while low-fat and high-fat dairy diets saw 32 percent and 25 percent decreases, respectively.

Not all patients were metabolically healthy at the beginning of the study—925 were recorded as having prediabetes, and of that fraction, 196 developed type 2 diabetes over more than a decade. For these patients, diets higher in high-fat dairy and cheeses resulted in a 63-70 percent lower risk of incident type 2 diabetes. The inverse response to cheese consumption, the authors wrote, seemed to be the “strongest dose-response association” of the study.

“Although prior studies have shown a relationship between cheese consumption and a lower risk of type 2 diabetes, I was surprised by the strength of the association in our study,” Jacques said.

Overall, Jacques and colleagues found that glycemic status at baseline, as well as various types of dairy intake, determined the results of the trial. Patients consumed all types of dairy, they wrote, including a cohort of 36 percent of participants who didn’t touch yogurt during the 12 years. Younger patients with a higher BMI and lower triglyceride concentrations tended to consume the most dairy, and those who did consume the most also tended to eat more whole grains and fewer vegetables, less meat, fewer sugar-sweetened beverages and had a lower alcohol intake.

Jacques said that next, his team is “planning to identify metabolites associated with different types of dairy consumption to determine the possible mechanisms by which dairy foods may influence the risks of prediabetes and type 2 diabetes.”