Replace meat with potatoes and beans for weight loss, a new study suggests

Because potatoes are high in carbohydrates, they have developed a reputation for leading to weight gain and have been associated with an increased risk of type 2 diabetes. They are often found on lists of foods to avoid, especially for people with insulin resistance. However, a new study published in the peer-reviewed medical journal Journal of Medicinal Food found that potatoes actually did not increase the risk of type 2 diabetes and were full of key nutrients and health benefits.

The Pennington Biomedical Research Center study examined how a diet that includes potatoes affects key health measures. “We have shown that, contrary to common belief, potatoes do not have a negative impact on blood glucose levels. In fact, people who participated in our study lost weight,” Candida Rebello, PhD, assistant professor at Pennington Biomedical and study co-investigator, said in a statement.

The study involved 36 participants between the ages of 18 and 60 who were overweight, obese or insulin resistant. Insulin resistance refers to a health condition in which the body’s cells do not respond well to insulin and glucose does not enter the cells to produce energy. Insulin resistance is linked to obesity, high blood pressure, high cholesterol and type 2 diabetes.

Participants were fed precisely controlled diets of widely available common foods. Both diets were high in fruits and vegetables and replaced about 40% of typical meat consumption with either beans and peas or potatoes.

“The key aspect of our study is that we did not reduce the size of the food portions, but reduced their caloric content by including potatoes,” Rebello explained.

“Each participant’s meal was tailored to their individual caloric needs, but by replacing the meat content with potatoes, participants felt fuller, faster, and often didn’t even finish their meal. In fact, you can lose weight with little effort,” Rebello pointed out.

Replacing meat with potatoes and beans

Previous studies have shown that eating beans and peas improves blood glucose levels in people with newly diagnosed type 2 diabetes. To increase the dietary fiber content of potatoes, they were boiled with their skins intact and then refrigerated for 12 and 24 hours.

Potatoes were incorporated into main lunch and dinner entrees such as shepherd’s pie, and served with side dishes such as mashed potatoes, baked potato wedges, potato salad, and scalloped potatoes with lunch and dinner entrees.

“We prepared the potatoes in a way that maximized their fiber content. When we compared a diet with potatoes to a diet with beans and peas, we found that they were equal in terms of health benefits,” Rebello said. “People usually don’t stick to a diet that they don’t like or that doesn’t have enough variety. The meal plans offered a variety of dishes and we showed that a healthy eating plan can have varied options for people who strive to eat healthy. Plus, potatoes are a fairly inexpensive vegetable to incorporate into a diet.”

The study helped identify the impact of potatoes on our metabolism and adds to a growing body of research on obesity and type 2 diabetes. John Kirwan, Ph.D., principal investigator of the study and executive director of the Pennington Biomedical Research Center, explains that this research is just one step towards a better understanding of obesity.

“Obesity is an incredibly complex disease that Pennington Biomedical is tackling on three different fronts: research that looks at how and why our bodies react the way they do, research that looks at individual responses to diet and physical activity, and policy discussions and community programs that bring our research into strategies that our local and global communities can use to live healthier lives,” Kirwan said in a statement. “This new data on the impact of potatoes on our metabolism is an exciting addition to the arsenal of evidence that we need to do just that.”

Potato protein helps in muscle development

Potatoes have additional health benefits beyond improving metabolism and glucose levels. A study published earlier this year in the journal Science Medicine and Science in Sports & Exercise found that potato protein can be just as effective as animal milk in building muscle.

The study hypothesized that because potato protein and animal milk protein have a very similar amino acid composition, both could have a similar effect on muscle protein synthesis, or how the body converts amino acids into skeletal muscle protein.

In a double-blind study involving 24 healthy men, researchers found that both protein sources were comparable. “Ingestion of 30 grams of potato protein concentrate increases rates of muscle protein synthesis at rest and during recovery from exercise in healthy young men,” the study concluded. “Rates of muscle protein synthesis after ingestion of 30 grams of potato protein did not differ from rates observed after ingestion of an equivalent amount of milk protein.”

Nicole Axworthy is the VegNews news editor and cookbook author DIY Vegan.