America’s diet quality moved from an F to a D. Here’s how to turn yours into an A

There’s a crack of light shining through the dark clouds of America’s battle with poor nutrition and subsequent health issues, according to a new study that analyzed two decades of nutritional data.

“There is good news. Americans are starting to hear the message about nutrition, and some companies and restaurants are starting to make healthier products. It’s a little bit of an improvement,” said senior study author and cardiologist Dr. Dariush Mozaffarian, director of the Food is Medicine Institute at Tufts University in Boston.

However, he added, the majority of the improvement occurred between 1999 and 2010, with no advances in nutrition after that.

“We have stalled as a nation — and that does not bode well for our health,” Mozaffarian said. “If I was grading America on its diet, I’d give it a D—just up from an F.”

An upward trend, but more is needed

The number of adults in the United States who ate a poor diet decreased from about 49% to just over 37% between 1999 and 2020 — a drop of 11.4%, while those who ate somewhat better nutritionally rose by 10.5%, the study found.

A poor diet was defined as one with too many refined grains, processed meat and sugary beverages, including fruit juice, as well as ultraprocessed foods full of added sugar, salt and fat. Healthy choices such as fruits and vegetables are extremely low in this eating style.

“Intake of fruits and vegetables didn’t increase at all over this 20-year period, which is pretty striking,” Mozaffarian said.

An ideal diet included at least the daily recommended servings of fruits and vegetables, as well as more beans, whole grains, nuts and seeds. Dietary guidelines such as those from the American Heart Association suggest eating 4 to 5 cups a day of canned, fresh or frozen fruits and the same amount for vegetables.

The nutritionally ideal diet also contained few sugary beverages, processed meats, refined grains and ultraprocessed food, which is often high in added sugars, fat and salt, the study said.

Unfortunately, the number of people who ate an ideal diet –— which included those 9 cups of fruits and vegetables — rose less than 1%, the study found.

“People often ask me, ‘Well, if the diet’s slowly improving, why is obesity and diabetes still going up?’ It’s still going up because only 1.58% of Americans have an ideal diet. We still have a long way to go,” Mozaffarian said.

More than a million Americans die each year from diet-related diseases such as obesity, cancer, heart disease and type 2 diabetes, according to the US Food and Drug Administration, while unhealthy diets and food insecurity cost the United States an estimated $1.1 trillion in healthcare expenditures and lost productivity annually.

“I think it is correct to emphasize that diet quality remains dismal in the US. There is no secret why Americans are experiencing epidemics of obesity and diabetes and declining life expectancy,” said Dr. Walter Willett, a professor of epidemiology and nutrition at the Harvard T.H. Chan School of Public Health in Boston, in an email. He was not involved in the study.

Food insecurity is a major issue

The study, published Monday in the Annals of Internal Medicine, analyzed dietary information on nearly 52,000 US adults who participated in the National Health and Nutrition Examination Survey, or NHANES.

Nutritional advances were highest among women, younger adults, Hispanic adults, and people with more education and higher incomes who had access to private health care insurance. Fewer gains were seen in men, Black or older adults and people with less income, lower educational levels, non-private health insurance, and food insecurity issues.

“Disparities in the population by education and income and race and ethnicity are the same or sometimes getting worse,” Mozaffarian said.

The study found that people with lower income saw a 5% improvement in nutritional quality, while those with higher incomes improved their nutritional score by 16%.

“We do need to avoid just blaming the victims of the dysfunctional US food system for the terrible diets documented in the survey,” Willett said. “We fail to educate students about nutrition in our schools and feed them unhealthy diets.

“Our health care system is missing in action almost completely, we allow advertising to seduce children into junk foods and beverages that kill them prematurely, and we indirectly subsidize unhealthy foods in many ways that make healthier options relatively more expensive and less available to low-income Americans,” he said.

How to improve your nutrition

There are easy steps you can take to boost the nutritional quality of your diet, experts say.

Cook at home as often as possible: “My top suggestion is to shop at the grocery store as much as you can, rather than getting your food at a coffee shop, sandwich shop or quick-serve restaurant,” Mozaffarian said.

Even eating at a full-service restaurant should be limited, he added. Prior research by Mozaffarian and his team found about 80% of all food consumed by Americans from restaurants was of poor diet quality.

“Shockingly, even when we compared fast food versus sit-down restaurants, there wasn’t a dramatic difference in quality,” he said.

Instead, try to choose minimally-processed foods to cook at home and avoid the ready-to-heat-and-eat convenience foods so prevalent at the grocery store. Bring your lunch and snacks to work.

Limit refined grains. Overall, the biggest contributor to the poor quality diet of Americans is refined grains, at 5.2 servings per day — “almost two servings a meal of refined grains such as refined bread, refined rice, crackers, chips, and other ultraprocessed foods,” Mozaffarian said.

Whole grains still contain the bran and germ, which is a nutritional powerhouse full of healthy fats, antioxidants, minerals and E and B vitamins. Whole grains take longer to digest, don’t raise blood sugar as quickly as refined grains and contain more fiber, which can reduce the risk of chronic disease, promote weight loss, and improve digestion.

“Some examples of whole grains include barley, bulgur, farro, millet, quinoa, black rice, brown rice, red rice, wild rice, oatmeal and popcorn,” according to My Plate, the US Department of Agriculture website.

Refined grains such as white flour, corn grits, white bread and white rice have been milled, removing the bran and germ, to give them a finer texture and longer shelf life. Milling also removes nutrients like dietary fiber, iron and vitamins. Refined grains are found in nearly all ultraprocessed foods, including breakfast cereals, desserts, pastries, bread and crackers.

Replace refined grains. Instead, nourish your gut microbiome with fruits and vegetables, beans, nuts and seeds and minimally-processed whole grains,” Mozaffarian said. Fermented foods such as yogurt, sauerkraut and kimchi can also help the microbiome, he added.