Life expectancy in the United States went up for the first time in four years in 2018, thanks largely to a decrease in death rates from cancer and drug overdoses, the Centers for Disease Control and Prevention said Thursday.

Still, experts noted that the report, from the CDC’s National Center for Health Statistics, is not all good news: The U.S. also saw an increase in suicide and flu death rates in 2018.

The report means that babies born in 2018 are expected to live slightly longer — 78.7 years vs 78.6 — than babies born in 2017.

Rates of death for six of the country’s 10 leading causes of death dropped for the first time since 2014; the decline in cancer death rates and unintentional injury rates — a category that involves drug overdoses — accounted for nearly half of the decline. Drug overdose death rates, in particular, went down for the first time in nearly three decades.

Rates of cancer-related deaths decreased by more than 2 percent in 2018, from 2017, while death rates due to unintentional injuries and chronic respiratory disease both dipped by nearly 3 percent. The rates of stroke and Alzheimer's disease deaths declined by almost 1.5 percent, and heart disease death rates declined by less than a percent. Deaths related to diabetes and kidney disease stayed about the same.

According to the report, increases in mortality rates were seen in just two categories: suicide, which increased 1.4 percent from 2017 to 2018, and influenza or pneumonia, which jumped by more than 4 percent. (Of note, the 2017-2018 flu season was the deadliest since the 2009 H1N1 pandemic, with 61,000 deaths.)

The fact that death rates due to disease generally decreased in 2018 is hopeful, said Irma Elo, chair of the sociology department and a research associate at the Population Aging Research Center at the University of Pennsylvania. But the U.S. is not out of the woods yet, she added.

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Elo attributed the decline in deaths from unintended injuries to the drop in drug overdose deaths, but advised cautious optimism — while 2018 did see a nearly 5 percent decrease indrug overdose deaths overall, deaths due to synthetic opioids such as fentanyl went up 10 percent. In addition, from 2012 to 2018, death rates involving cocaine increased threefold.

And though life expectancy for infants as well as people over age 65 increased by around 1 percent in 2018, the 78.7-year life expectancy is still lower than it was in 2014, a number that worries experts who point to the big picture.

“The new data shows an increase in life expectancy that’s statistically significant,” said Steven Woolf, director emeritus of the Center on Society and Health at Virginia Commonwealth University. “If this trend continues, that’s great and would be welcomed news, but we shouldn’t draw conclusions based on this single year to year change. The overall trend is that people in the U.S. have a lower life expectancy than people in other high-income countries.”

The average life expectancy among all 36 countries that make up the Organization for Economic Cooperation and Development is just over 80 years. Even with the improvement, the U.S. lags behind.

Indeed, a separate report — also published Thursday — from the Commonwealth Fund compared the U.S. to other wealthy countries, highlighting the U.S.’ last place status for life expectancy. That report also looked at Australia, Canada, France, Germany, the Netherlands, New Zealand, Norway, Sweden, Switzerland and the United Kingdom.

Woolf, who was not involved with either report, attributed this trend to the large number of people, especially those living in the economically-depressed Rust Belt, who are dying years before they're expected to, a phenomenon he said is “uniquely American.”

“There’s a tendency to think of health statistics in terms of health care, but health is about more than the health care system. Policymakers must recognize that the decisions they’re making about jobs, education and infrastructure investments, are health policies and have consequences not only to pocketbooks but to life expectancy,” Woolf said.

Expanding jobs that pay wages that are on par with today’s rising health care and housing costs could make a big difference in easing financial stress, Woolf said. In addition, he said, the U.S. must invest in education, especially on skills that are in demand that could help people land 21st century jobs.

“I don’t think these are getting the priority they should, and what these statistics are telling us is that it’s costing people their lives,” Woolf told NBC News.

The fact that almost 40 percent of Americans are obese also likely plays a role in the U.S. falling behind other countries.

The Commonwealth Fund report found that Americans are twice as likely than people living in most other wealthy countries to be hospitalized for hypertension or diabetes, two diseases associated with obesity.

That report also found that despite living shorter lives, Americans spend nearly two times more on health care than any other high-income country. In addition, suicide rates among Americans are twice as high as in the U.K.

The numbers illustrate a larger societal problem, Elo said.

“Suicide mortality going up may be tied to the drug epidemic, but is also an indicator of stressful life events. The safety net in the U.S. is much less secure than it is in other countries,” she said.

On a positive note, the sharp decline in the number of cigarette smokers in the past four decades has likely had a positive impact on smoking-related deaths including cancer and respiratory disease, especially because quitting smoking before turning 40 reduces a person’s risk of dying from smoking-related disease by about 90 percent, according to the CDC. Advances in cancer treatments and early screening are also positive influences on U.S. life expectancy.

In the end, the fact that American infants are projected to live longer than they would have in 2017 is a victory.

“People should be encouraged but still understand that there is something fundamentally wrong with our health pattern in the U.S.,” Woolf said. “When you look at this longer-term trend over the past few decades, it’s clear that we need to make some fundamental changes in the way we approach life in America if we’re going to sustain this decrease.”

If you or someone you know is in crisis, call the National Suicide Prevention Lifeline at 800-273-8255, text HOME to 741741 or visit SpeakingOfSuicide.com/resources for additional resources.

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