After decades of progress, younger generations are facing worse heart disease risks, study suggests

Younger generations in the U.S. have higher blood sugar levels than their older counterparts, fueled in part by the ongoing obesity epidemic, according to a new study published in JAMA Network Open. While medications and increased awareness have helped to steadily drive down the average cholesterol and triglyceride levels for the last several decades, the researchers found that the encouraging decline in these lipids is starting to slow.

So why are some of these risk factors for heart disease — the No. 1 cause of death worldwide — not improving and possibly getting worse among the youngest generations? Here’s what experts think.

What the new study found

Using data on hundreds of thousands of Americans born between 1920 and 1999, researchers from Northwestern University Feinberg School of Medicine calculated the average cholesterol, triglyceride and glucose levels for each birth cohort (people born in each decade). They also assessed how average body mass index had changed over time.

First, the good news: Average cholesterol and triglyceride levels — lipids that, when levels are too high, build up to clog and harden blood vessels — have been on a downward trajectory over recent decades. But that progress has slowed: Among people ages 20 to 39, cholesterol levels fell just 5.5% between 1999 and 2018, compared to a drop of more than 14% over the same period among those 60 and older.

The study also found that the average levels of glucose, or blood sugar, have been rising for each successive generation at an accelerated rate.

So what’s going on?

Experts, including the study’s lead author, Northwestern research assistant professor of cardiology Xiaoning “Jack” Huang, credit treatment improvements for the win when it comes to lipid levels. “We have been doing tremendous things with the use of statins to reduce [lipids] in the general population in recent decades,” Huang tells Yahoo Life. Statins act on the liver to prevent the body from overproducing cholesterol and triglycerides. They can reduce “bad” cholesterol by between 30% and 50%, and lower triglycerides by 10% to 50%.

But adoption of the drugs got off to a sluggish start after their initial approval in 1987. As uptake of statins accelerated, so too did declines in lipid levels. Now that trend is slowing, which may reflect “persistent unhealthy dietary and other behavioral habits, such as higher intake of processed foods [and] rising obesity rates, which offset some benefits of lipid management,” Dr. Harlan Krumholz, a Yale University cardiologist, tells Yahoo Life. As powerful as statins are, “there’s only so much medications can do,” Dr. Lori Daniels, a University of California, San Diego cardiologist, tells Yahoo Life.

Rising obesity rates, experts agree, are also a key factor driving up blood glucose levels, which raise risks for type 2 diabetes and, in turn, heart attacks and other cardiovascular problems. The new study wasn’t designed to determine whether obesity was a cause of the rising glucose levels. However, it found that obesity indirectly “mediated,” or contributed to, 20% of the generational blood sugar increases. “Obesity is only part of the answer, and probably other risk factors are playing a major part,” says Daniels. Younger generations, she says, are more likely to eat highly processed foods and have poorer-quality diets, be more sedentary amid “the rise of cellphone culture” and be more stressed.

Worth noting: The study’s data was largely collected before game-changing weight loss drugs such as Ozempic and Wegovy were being widely used. “If we’re changing the outcome of obesity with ... medication, we’re also changing diabetes and cardiovascular disease [risks],” Harrison Memorial Hospital cardiologist Dr. Yaz Daaboul tells Yahoo Life.

What can you do to protect your health?

For one, just being aware of “silent killers” including high lipid and glucose levels is crucial, says DeBull. He advises anyone in their early 30s to get at least one lipid screening, and for those 45 and older to get screened for diabetes or prediabetes, along with lipid level testing. These screenings will help your health care provider guide you on what lifestyle changes to make, and whether you should consider medications.

But perhaps more importantly, you can start by making lifestyle changes like eating a Mediterranean diet low in red meat and processed foods, and exercising (for example, even spending a few minutes taking the stairs instead of an elevator can help cut heart attack risk).

The American Heart Association sums up what you can do to reduce your cardiovascular risks neatly in what it calls “Life’s Essential 8”:

• Eat better.

• Be more active.

• Quit tobacco.

• Get healthy sleep.

• Manage weight.

• Control cholesterol (with statins or other medications, as well as diet and exercise).

• Manage blood sugar.

• Manage blood pressure.

Forming these healthy habits, “even in this modern day and age — and maybe more so — when it’s so easy to be inactive at your desk or on your phone all day and get fast processed foods, we really need to keep up the effort,” says Daniels. “Medications, in the right situations, can clearly help, but only so much; they can’t be a singular strategy in isolation,” she adds.