Dr. Abraham Thomas doesn’t judge his patients’ health based on their appearance – even if they are older, frail-looking adults waiting in his Mokena office, as new data shows young adults are dying at higher rates.

“The millennials always look healthy,” said Thomas, a board-certified internal medicine doctor at Silver Cross Hospital in New Lenox. “But they’re the ones who have all the hidden risks. And, interestingly, they are at an increased risk to die … and there is a lot of data to back this up.”

For the first time since 1850 – when life expectancy began rising – the trend is reversing among young adults in the U.S. A new study from Boston University School of Public Health reveals a surge of “excess deaths” among people ages 25 to 44, driven largely by drug overdoses, suicide and unintentional injuries.

Researchers analyzed almost 3.4 million deaths from 1999 to 2023 and compared mortality trends from the early 2000s with today’s patterns, according to the study “Mortality Trends Among Early Adults in the United States, 1999-2023.”

Almost three-quarters of early adult excess mortality in 2023 came from five causes: drug poisoning (31.8% of excess mortality), the residual natural-cause category (16.0%), transport-related deaths (14.1%), alcohol-related deaths (8.5%), and homicide (8.2%), according to the study.

“Additionally, the combined contribution of cardiometabolic conditions, including circulatory and endocrine, metabolic, and nutritional, was substantial (9.2%),” according to the study.

Doctors in the south suburbs and across northern Illinois say they’re seeing this firsthand.

According to Blue Cross Blue Shield’s report “The Health of Millennials,” almost 73 million people in the U.S. were born between 1981 and 1996. These individuals are “experiencing double-digit increases in prevalence for eight of the top 10 health conditions,” including a 21% increase in cardiovascular conditions and a 15% increase in endocrine conditions, including diabetes.

Health decline begins at age 27 on average, according to Blue Cross Blue Shield.

Other national data shows similar patterns.

In 2023, the Population Reference Bureau discovered that women born between 1981 and 1999 have increased rates of suicide and maternal mortality.

A study from Trust for America’s Health found that more than 152,000 Americans died from alcohol- and drug-induced fatalities and suicide in 2017 – more than twice as many as in 1999 and “the highest number ever recorded.”

But the single largest driver of death for millennials was opioid overdose, which increased 500% between 1999 and 2017, Thomas said.

“That is staggering,” Thomas said.

Economic pressure and chronic stress

Dr. Mark D. Gomez, a board-certified internal medicine physician and concierge medicine specialist with Endeavor Health Medical Group in Naperville, said millennials have dealt with both the Great Recession and the COVID-19 pandemic since entering the workforce.

Consequently, they’ve faced “economic pressure and debt,” which drove chronic stress in their lives, Gomez said.

In fact, the national median age of the average first-time home buyer now is 40 simply because younger people can’t afford to buy a home. Factors include rising living costs, higher student debt and job uncertainties, Thomas said.

“Wages aren’t rising in comparison to the cost of living,” Thomas said.

Gomez explained how stress affects the release of adrenaline and cortisol, which is typically self-limiting unless stress is unrelenting.

“Too much exposure to cortisol and stress disrupts the body’s processes,” Gomez said.

Chronic stress is linked to anxiety, depression, heart disease, hypertension, heart attacks, strokes, weight gain, sleep disruption and memory problems, Gomez said.

Heavily processed diets and sedentary lifestyles drive obesity, diabetes and colon cancer – now the leading cause of cancer death in people younger than 50, according to the American Cancer Society.

When millennials are diagnosed with colon cancer before age 45, they’re typically at a higher stage, Gomez said, because they haven’t yet reached the recommended screening age.

Thomas views obesity as both a socioeconomic and a health issue. Too many millennials can’t access healthy food and rely on fast food because “it’s all they can afford.”

“When I was growing up, McDonald’s was a treat for us,” Thomas said.

But millennials often don’t address these issues because they can’t afford it.

Thomas said the high cost of health insurance – including high copayments, underinsurance and coverage gaps – puts preventative health care out of millennials’ reach.

“Things that are minor to start become more serious when they can’t go to see a doctor,” Gomez said.

For instance, early-onset Type 2 diabetes (before age 40) can lead to developing complications sooner: heart disease, peripheral vascular disease and kidney disease, Thomas said.

What concerns doctors most is that many of these risks remain hidden until it’s too late.

For a generation that often appears healthy, the warning signs aren’t always visible, but the consequences increasingly are.