A new study by the Harvard School of Public Health shows that although the overall American diet improved between 1999 and 2010, there has been a disconcerting increase in the gap between the diets of the rich and the poor.

Things like better national focus on reducing the amount of trans fats in fast food and other high-calorie snacks have helped to better our eating habits. However, this study, published on September 1 in the journal JAMA Internal Medicine suggests that not all Americans can afford good-quality food.

Dong Wang, the lead author of the study, said that the study was direct evidence that although the increased national attention on nutrition and health is doing some help, "these efforts need to be expanded," especially for the poor.

Dietary equality across socioeconomic groups in America is important because having a poor diet is a major cause for some types of disease, such as cardiovascular disease, type 2 diabetes, and cancer. Wang urged public officials to take note of the importance of spending a small amount of money on creating ways for the poor to get access to good food and better education about nutrition, to save a huge amount of money in medical bills through preventive care. Another recent study, for example, showed that type 2 diabetes patients that followed a program emphasizing better nutritional self-care and better exercise programs helped save an average of $500 a month in medical bills, regardless of the severity of the individual person's illness.

The Harvard study found that almost half of the improvement in the overall American diet from 1999 to 2010 came from reduction in consumption of trans fats. The study suggested that the concerted efforts of health organizations and lawmakers to reduce trans fats in junk food and increase awareness of the problem had more of an overall effect on health than asking individual people to simply make the change for themselves.

The study also found that Americans are eating more whole nuts and fruits, and other types of unprocessed foods. However, Americans are not eating more whole vegetables, and they are still eating too much red meat and processed meat. The study's authors called the upward trend in salt consumption "disconcerting."

Some of the things which the study's authors suggested contributed to the increasing gap between the diets of the poor and the rich were less access to high-quality food in poor neighborhoods, less education about nutrition offered to the poor, and too high of a price for good food.

"The overall improvement in diet quality is encouraging, but the widening gap related to income and education presents a serious challenge to our society as a whole," said Walter Willett, a senior author of the research study.