“One interesting detail that they mention in the study was that they cooked and cooled the potatoes prior to serving them to participants. This process can make some of the starch contained in the potato slower to digest than before, and this can improve insulin sensitivity and glucose tolerance when consuming such food.”

“It is also important to note that they consumed other foods—such as protein foods—with the potatoes, which can improve glycaemic response as well,” she added.

Overall, the researchers found that participants on both diets did not see a significant drop in blood glucose levels. However, both groups experienced weight loss and reduced insulin resistance.

Amy Kimberlain, registered dietitian nutritionist and spokesperson for the Academy of Nutrition and Dietetics Media, who was not involved in the study, told MNT:

“This study helped show that utilizing foods that reduce the energy density of the diet will not only allow for an improved insulinemic response but also help to promote weight loss as well.”

“Additionally, this study helps to continue the conversation that we can improve different risk factors in people by making changes in our diets (eating patterns) but still continue to eat foods that we enjoy.”
— Amy Kimberlain

The study did have several limitations. First, it included a small sample size, so future studies can work on including more participants. Most participants were female, indicating more diverse follow-up may also be needed.

The study was also only eight weeks long, so more long-term studies are required to look at long-term results.

The researchers noted that the differences between participants’ baselines of Body Mass Index (BMI) and fasting insulin levels did ultimately affect the study’s outcomes. There were also some difficulties in study completion due to the COVID-19 pandemic.

Kimberlain also noted that researchers had tight control over food preparation but that translating this into real-life practice could be more difficult.

“These meals were prepared for the people in a metabolic kitchen, meaning the ability to confirm what people were eating (calories/content/etc.) was there. And while this is a study and they used this to have the ability to confirm intake, to verify and/or see if this is effective in the long-term with people, it’d be important for people to be able to do this on their own (after receiving instruction on how to prepare the examples of meals they received),” she said.

Overall, the study demonstrates that preparation and food choices are essential components of diabetes control. Further research is warranted to confirm how starchy vegetables like beans and potatoes can contribute to healthy diets for people at risk for type 2 diabetes.