As 2015 winds down and another year begins, there are many positive signs that people in the United States will be healthier in 2016.
Recent reports show that some important indicators of the nation's public health are changing for the better, and there are encouraging findings suggesting that many Americans are slowly making progress toward becoming a little bit healthier.
Death rates, which have been dropping for decades, continue to decline for most of the population, and the rates for some of the leading causes of death, such as heart disease, stroke and cancer are decreasing as well, even as the American population is aging, said Dr. J. Michael McGinnis, an epidemiologist and senior scholar at the National Academy of Medicine in Washington, D.C. "On balance, there's good news for the most part, and many health indices are continuing to improve," he told Live Science.
In a recent study, published in October in the journal JAMA, researchers reviewed death rates in the United States between 1969 and 2013 for people younger than 75, and found a downward trend in the yearly death rate from all causes combined, as well as for five of the top six causes of death, including heart disease, cancer, stroke, diabetes and unintentional injuries. (However, the researchers noted, the death rate from the sixth cause studied — chronic obstructive pulmonary disease, which includes lung conditions such as emphysema and chronic bronchitis — increased over the study period.)
During the 44-year study period, the analysis found that the death rates from stroke and heart disease had the most substantial declines: The death rate from stroke in people under age 75 fell 77 percent, while the death rate from heart disease dropped about 68 percent. [5 Surprising Ways to Be Heart Healthy]
The researchers also found that over the study period, the death rate from unintentional injuries (such as car and airplane accidents, falls, fires and drug overdoses) fell by about 40 percent, cancer deaths fell by about 18 percent and deaths from diabetes dropped by about 17 percent.
There is no question that the decline in the rate of death from heart disease, stroke and some cancers is due to the substantial decrease in tobacco use among Americans, McGinnis told Live Science. Tobacco hasbeen the leading cause of preventable death for over 50 years, but now that the percentage of American adults who smoke has dropped below 20 percent (it was 16.8 percent in 2014, according to the Centers for Disease Control and Prevention), the country is seeing tremendous health benefits, he said.
But although the declines in the death rates from heart disease and stroke were really dramatic in the 1970s and 80s, the rate of decrease is beginning to slow in recent years as the prevalence of obesity and type 2 diabetes increases, McGinnis said.
The data also showed that fewer Americans are losing their lives because of unintentional injuries. This trend is the result of automobile safety, the wider use of seat belts by both drivers and passengers, and an increased awareness of the risks of drinking and driving, McGinnis said.
The rates of drunk driving have fallen by nearly one-third since 2007, according to the latest survey conducted by the National Highway Traffic Safety Administration, but on the flip side, the survey reported a boost in the number of drivers using marijuana or other illegal drugs.
McGinnis also noted that the life span of Americans has lengthened, from 45 to 50 years at the beginning of the 20th century to closer to 80 today. "Historically, that's a revolutionary change because of dramatic improvements in nutrition, sanitation, the development of antibiotics and a variety of basic preventive health services, such as vaccinations and screenings, he said. [9 Healthy Habits You Can Do in 1 Minute (Or Less)]
Without question, one of the biggest public-health success stories is the prevention and treatment of cardiovascular disease, said Dr. Dariush Mozaffarian, a cardiologist and dean of the Friedman School of Nutrition Science & Policy at Tufts University in Boston.
Decreases in the rates of heart disease and stroke in the United States are due in large part to changes in the U.S. population in three key measures: reductions in the rate of smoking, lowering of average blood cholesterol levels and reducing the average blood pressure, Mozaffarian said. Policy changes and concerted, successful public-health efforts to reduce the number of Americans who smoke, such as bans on cigarette advertising, warning labels and prohibiting smoking in public places, have played a role in the drops, he said.
Changes in diet and eating habits may also be responsible for the lower levels of high cholesterol and high blood pressure seen in the American population, Mozaffarian told Live Science. Advances in treating these two conditions, such as new medications and medical procedures, also play a role in the drops, as well as factors such as improvements in maternal nutrition and a better understanding of the influence of gut bacteria, he suspects.
In fact, the percentage of U.S. adults with high cholesterol levels dropped from 18 percent in 1999 to 11 percent in 2014, according to the most recent data from the CDC.
On the dietary front, meat consumption among Americans is down, and levels of trans fat in the diet have also fallen due to policy changes, Mozaffarian said.
For example, food companies have been required to list the amountof trans fat on food labels since 2006, and in June 2015, the FDA gave manufacturers until 2018 to remove partially hydrogenated oils from their food products because the agency ruled that trans fat in processed foods is not "generally recognized as safe."
Although Americans tend to be slow to change their eating habits, there have been some small, but encouraging signs of progress. There has been a modest increase (fractions of a serving) in the consumption of fruits and vegetables, an increase in nut consumption and a movement away from fast food and sugar-sweetened drinks, such as sodas and fruit drinks, Mozaffarian said. Levels of sodium in the diet are flat (neither up nor down), and there has also been a slow reduction in the consumption of refined grains, such as white flour and white rice, and a slow increase in whole-grain consumption, he said. [Diet and Weight Loss: The Best Ways to Eat]
In response to consumer interest in healthier foods, some food manufacturers including national brands such as Kraft, Nestlé USA and General Mills, and some restaurant chains, such as Panera, Pizza Hut and Subway, have started to remove artificial flavorings, colors and additives from their products and replace them with natural ingredients, according to several news sources.
And some Americans may be getting off the couch more: There has been a modest increase in the number of U.S. adults who are meeting weekly federal guidelines for moderate or vigorous physical activity in this decade compared to the last decade, according to the latest data from the CDC.
Not everything is rosy
Among all the good news about Americans' health, there are plenty of areas where there is room for improvement, and some lingering troubling signs.
Obesity is still a major health problem. The latest figures show that obesity rates in at least one age group — preschool children ages 2 to 5 — have decreased in the last decade, according to a study published in the journal JAMA in 2014. But obesity rates in other groups are holding steady, or rising.
One thing that needs to be underscored is that the health gains seen are not equitably distributed across the U.S. population, McGinnis said. For example, rates of obesity and diabetes are higher in low-income communities and among certain ethnic and racial groups. Disparities are also evident in cigarette smoking, where smoking rates are higher among people with lower incomes and less education.
In addition, there has been a very unfortunate increase in deaths from opioid addiction in the United States in the last half-decade or so, McGinnis said.
Another challenge that causes substantial problems in the United States is in the area of behavioral health, which includes mental health concerns, depression and substance abuse, McGinnis said. People with behavioral health issues not only have medical problems that need attention, but they also have social problems related to housing, employment and social support that need more efficient services than the country currently offers, he said.
The health care system is not yet able to effectively deal with behavioral problems because these services may not be fully integrated into primary care, and people may have trouble getting care for these issues, McGinnis said.
Mozaffarian offered a similar opinion: As the new year approaches, the psychological health of Americans is worse than it has been in the past, and health disparities in this country are much worse than they have been in the past. [5 Controversial Mental Health Treatments]
The health care system has had a modest effect on the health of Americans, but the major drivers of improved health are public-health efforts and policies — such as better air and water quality, vaccines and public safety, Mozaffarian said.
Many of the country's big health problems that need improvement are related to diet, and that is a good place for Americans to focus in 2016, he said.
"Small changes in diet can accelerate the good health trends and reverse the bad," Mozaffarian said.