Dec. 24 (UPI) -- In 2018, researchers continued gaining ground on cancer and learning how Alzheimer's disease and other dementias work. They found new ways to make prosthetic limbs feel like real ones, and put into practice methods to reduce hospital-borne infection and attempt to push off antibiotic resistance.
At the same time, life for those in the U.S. is getting shorter -- with opioids and guns pointed to as major culprits -- a mystery disease spread across the country during the year, and teenagers learned they can get a nicotine fix without smoking cigarettes.
As the year winds down, here's a look at the five biggest health stories of 2018.
Teen vaping soars
Cigarette smoking reached an all-time low in the U.S. this year, but 37 percent of high schoolers admitted they have vaped at least once, up by almost 10 percent from last year, according to the New England Journal of Medicine.
That's why the U.S. Food and Drug Administration declared a war on the e-cigarette industry, sending a harsh letter warning companies to control the teen vaping "epidemic" or face a ban. The agency followed up by raiding the office of Juul, which has more than 70 percent of e-cigarette market share in the United States.
Since then, Juul has pulled back its social media promotion and stopped selling some flavored pods in stores to comply with FDA requests keep the e-cigarettes out of teens.
Opioid deaths climb, as life expectancy falls
More than 70,000 people died from drug overdoses in 2017, pushing up deaths in that category to a record high and driving down the life expectancy in the United States. The average age of death crept down slightly from 76.2 in 2016 to 76.1 in 2017 -- the second year in a row it dropped.
Opioids like fentanyl and tramadol drove up drug-related deaths by 45 percent between 2016 and 2017, causing nearly 30,000 of those fatalities last year.
The CDC has continued to say the opioid epidemic is getting worse, with prescription pills and illicit drugs plaguing communities across the country. The FDA is now encouraging all users of opioids -- those receiving prescriptions, and those misusing the drugs -- to keep overdose medications on hand as a preventive measure.
Gun deaths reach 40-year high
Gun violence continues to increase in the United States, and this year data from the Centers for Disease Control found that 39,773 people died from gun violence in 2017 -- the highest number of gun deaths since 1979.
"In 2017, nearly 109 people died every single day from gun violence. Gun violence is a public health epidemic that requires a public health solution, which is why we must immediately enact and implement evidence-based interventions - like permit-to-purchase policies and extreme risk laws," Adelyn Allchin, director of public health research at Educational Fund to Stop Gun Violence, said earlier this month.
In particular, black men were found to be twice as likely as white men to die before age 20 from gun violence than any other group.
Experts encourage more exercise
About 80 percent of Americans aren't exercising enough, bringing on obesity that leads to illnesses costing nearly $117 billion dollars in annual healthcare costs. To combat the problem, the Centers for Disease Control and Prevention has rolled out new guidelines to exercise, recommending 150 minutes each week of moderate-to-vigorous aerobic activity.
Those bleak statistics are moving people to action. CDC researchers reported that close to half of all Americans are reportedly attempting to lose weight.
Polio-like disease spreads
A condition that paralyzes children has turned up in 31 states around the U.S, puzzling healthcare professionals on what to do next. The CDC has confirmed 165 cases of Acute Flaccid Myelitis, or AFM, that largely strikes children and causes potentially life-threatening paralysis, as well as respiratory illnesses and spinal cord disruption.
To solve this mystery, the CDC launched an investigative task force to contain the condition.
"I want to reaffirm to parents, patients, and our Nation CDC's commitment to this serious medical condition," CDC Director Robert R. Redfield said in a statement last month. "This Task Force will ensure that the full capacity of the scientific community is engaged and working together to provide important answers and solutions to actively detect, more effectively treat, and ultimately prevent AFM and its consequences."