In the study published in the British Journal of Nutrition eating non-fried potatoes also led to higher potassium and fiber intake when compared to eating refined grains such as white rice, white bread, or pasta.
“Certainly eating chips or french fries should be discouraged, but there are healthy ways to prepare potatoes, so I do think that lumping them all together is a little bit unfair to the poor potato,” said Emily Johnston, study co-author and a doctoral student in the department of nutritional sciences at Penn State. “We don’t want people to fear the potato, but we want to make sure that they eat it in a healthful way and in a controlled portion size.”
50 healthy adults were recruited for this study to examine the effects of consuming potatoes every day compared to the same number of calories in refined grains. Participant baseline blood pressure and arterial stiffness was measured at the beginning of the study, and blood samples were tested for fasting glucose, cholesterol, insulin, and other markers repeatedly throughout the study.
Participants were randomly assigned to replace their usual main meal side dishes with a study dish of either 200 calories worth of potatoes or refined grains as prepared by the Metabolic Diet Study Center at Penn State every day for 4 weeks. After a two week break participants switched their study dish for the other for an additional month.
The study dishes consisted of steamed or baked red, white, and gold spuds for the potatoes dish; the refined grain option was Spanish rice, pasta, garlic bread, or naan bread. All meals were prepared with minimal added salt, saturated fat or sugar and minimal ingredients being added for taste such as scallions, onions, cheese, or breadcrumbs.
Potassium and fiber intake was revealed to be significantly higher when eating potato options compared to refined grains; diet quality was also higher which was driven by higher vegetable intake. No evidence was found that consuming potatoes increased fasting glucose levels, there was no difference in cholesterol, insulin or other markers and the researchers concluded that there were no adverse cardiometabolic consequences.
Potatoes are a great source of potassium which is important for blood pressure regulation. According to the US CDC almost half of Americans have hypertension, says Johnston. Potatoes can be a part of a healthy diet; one medium baked potato can contain 4 grams of fiber, 4 grams of protein, 50% of the recommended daily intake of vitamin C, 25% of the RDI for potassium, one third of the RDI for vitamin B6, and 10% of the daily recommended intake of iron.
Potato side dishes should be no more than one fourth of your entire plate, portion size is key. One portion is roughly one medium potato which is about the size of a computer mouse. Stick to baking, roasting, or steaming as boiling can leach out nutrient content and frying is just a nutritional deal breaker. When it comes to potatoes try to skip the extras, go extra easy on the salt and try to avoid loading up with butter, bacon bits, or sour cream.
“We certainly want people to eat more non-starchy vegetables because we know the average American intake is well below recommendations,” Johnston said. “But starchy vegetables and refined grains do contribute some important nutrition as well, it’s just that we need to make sure we eat them in balance.”
