The diets of Americans are a little less sweet and a little crunchy, but there is still too much sugar, white bread and fat clogging the arteries, a study shows.
Overall, the authors estimate that there has been a modest improvement over the 16 years on the Government's Healthy Eating Index, from projected results from 56 to 58. This is hardly a cause for celebration – 100 is the best result.
Diets are still too heavy for foods that can contribute to heart disease, diabetes, obesity and other prevalent US health problems, said co-author Fang Fang Zhang, a nutrition researcher at Tufts University near Boston.
The study was published Tuesday in the Journal of the American Medical Association. The results are from an analysis of US government health studies from 1999 to 2016 involving nearly 44,000 adults.
"Despite the observed improvements," the authors wrote, "important dietary challenges" remain.
Among them: Made Americans cut down on snacks, hot dogs, fatty beef, butter and other foods containing saturated fat. The study found that these unhealthy fats increased from 11.5 percent to almost 12 percent of daily calories, above the 10 percent recommended limit.
And while the biggest change is a small drop in added sugars, from about 16 percent to about 14 percent, it's still too high. The government says less than 10 percent of daily calories should come from added sugars. Researchers say less sugary sodas have contributed to the decline, but Zhang notes that added sugars are often found in foods that don't even look sweet, including some yoghurt and tomato sauce.
Fruits, nuts, oatmeal and other whole grains are among the foods that adults eat a little more. However, each contributed less than 5 percent of daily calories in 2016, the study found.
Salt intake decreases slightly and a small decrease in fruit juice contributes to a decline in low-quality carbohydrates. But they still account for 42 percent of daily calories, including highly likely high-processed white bread and other refined grains, Giang says.
The study is based on personal health surveys conducted every two years that ask adults to recall what foods they have eaten in the previous 24 hours. Since 2003, adults have been asked this question twice every few days.
The study lists food groups, not individual foods; for example, "whole grains," not oatmeal and "refined grains," not white bread, but Zhang said the two foods are among the most common cereals in the American diet.
USA. dietary guidelines recommend a "healthy eating model" to reduce the chances of developing a chronic disease. The focus should be on foods with solid nutrients, including vegetables, fruits, whole grains, low-fat dairy products; plus a variety of protein sources, including seafood, lean meats and poultry, egg nuts and seeds, make recommendations.
During the years studied, the rate of diabetes in the United States almost doubled, over 7%; obesity rates have increased over many of these years, with about 70 percent of U.S. adults already overweight or obese. Heart disease remains the leading cause of death.
In addition to continued efforts in the field of public health, "Collaboration from the food industry" is crucial, the magazine said, including by reducing sugar, salt and saturated fat in foods.
Follow NBC HEALTH on Twitter & Facebook.