Are potatoes a vegetable or grain? Why lawmakers are fighting over how they're classified

Every five years, the United States Department of Health and Human Services (HHS) and the USDA publish the Dietary Guidelines for Americans, a collection of evidence-based recommendations to promote overall health and reduce the risk of chronic diseases. This generally includes commonsense advice about limiting one’s alcohol intake, monitoring portion size and eating a colorful variety of fruits and vegetables. However, some recent reports have farmers, trade groups and even politicians really concerned about what information will be contained in the next set of guidelines — specifically when it comes to potatoes. 

Currently, the government classified potatoes as a vegetable, but there has been speculation the 2025-2030 Dietary Guidelines for Americans could recategorize them as a grain. Some public health authorities, such as Harvard T.H. Chan School of Public Health, have already removed potatoes from the vegetable category, specifically because of how they impact blood sugar. 

That said, lawmakers, including 14 senators, have spoken out on the potential change, saying that any modification to potatoes’ current classification under the Dietary Guidelines “would immediately confuse consumers, retailers, restaurant operators, growers, and the entire supply chain.” 

From a nutritional standpoint, potatoes don’t actually affect our bodies in the same way that non-starchy vegetables — like spinach, broccoli or celery — do. Instead, according to Harvard’s School of Public Health, they are the type of carbohydrate that the body digests rapidly, causing blood sugar and insulin to surge and then dip. “In scientific terms, they have a high glycemic load,” the school’s staff wrote in a 2014 article titled “The problem with potatoes.” 

“For example, a cup of potatoes has a similar effect on blood sugar as a can of cola or a handful of jelly beans,” they write. “The roller-coaster-like effect of a high dietary glycemic load can result in people feeling hungry again soon after eating, which may then lead to overeating. Over the long term, diets high in potatoes and similarly rapidly-digested, high carbohydrate foods can contribute to obesity, diabetes, and heart disease.” 

The article authors pointed to a 2011 study that tracked the diet and lifestyle habits of 120,000 men and women for up to 20 years and looked at “how small food-choice changes contributed to weight gain over time.” The study found that people who increased their consumption of French fries, baked or mashed potatoes gained more weight over time, while people who decreased their intake of these specific foods gained less weight, as did people who increased their intake of other vegetables. 

However, Kam Quarles, CEO for the National Potato Council, doesn’t believe potatoes should be classified as grains because of other key elements of their nutritional makeup. In speaking with the National Dietary Guidelines Advisory Committee in September, he opened his statement by saying: “First: Potatoes are a vegetable.” 

“We understand that the Committee is considering changes to food groups within US dietary patterns. One of those discussions involves the interchangeability of starchy vegetables and grains,” Quarles said. “While NPC is sensitive to individual needs and cultures, we urge the Committee to recognize a potato is not a grain. Potatoes are the most widely produced vegetable in the U.S.” 

He continued: “Starchy vegetables and grains are two vastly different food groups that play distinctly different roles in contributing nutrients to the diet. Unlike grains, white potatoes are a strong contributor of potassium, calcium, vitamin C, and vitamin B6 and fiber. Research shows that diets high in vegetable consumption, including potatoes, promote healthy outcomes overall.” 

This is a point that was echoed in a letter to USDA Secretary Thomas Vilsack and HHS Secretary Xavier Becerra, sent and signed by two dozen senators last week. In the letter, the bi-partisan group — which included Senators Susan Collins (R-ME) and Michael Bennet (D-CO) — cited a 2013 study from the National Library of Medicine that said potatoes should be classified as a vegetable as they "contribute critical nutrients." The study said, "all white vegetables, including white potatoes, provide nutrients needed in the diet."

“Given this strong, fact-backed assertion produced from the National Library of Medicine study, it does not make any sense for your departments to reclassify potatoes as a grain,” the senators concluded. “We strongly urge you to avoid reclassifying potatoes as a grain or suggest grains and potatoes are interchangeable. Given the rapid timeline that the DGAs [Dietary Guidelines for America] are on, we ask that you provide us an update on this issue as soon as possible.”

The Grain Chain trade group also agrees that potatoes should continue to be classified as vegetables, saying that  putting potatoes in their category “could further exacerbate nutrient shortfalls.” 

Whether potatoes are officially classified as a vegetable or grain has implications beyond the nutritional recommendations provided within the guidelines; those recommendations impact how real-world programs, like the Supplemental Nutrition Assistance Program and National School Lunch programs, allocate benefits and budgets. 

“Our federal nutrition programs rely on the DGAs to ensure that program beneficiaries are receiving well-balanced, nutritious food,” the senators wrote. “Such a change could also come at a cost to our nation’s schools. Under the National School Breakfast and National School Lunch Programs, schools already struggle to meet vegetable consumption recommendations at a reasonable cost, and potatoes are often the most affordable vegetable.”