Cholesterol Levels Are Dropping In the U.S. Here’s What That Means

New data reveal good news about cholesterol levels in U.S.

According to the latest numbers from the National Center for Health Statistics, in 2015-16, 12.4% of adults had high cholesterol, defined as any measurement over 240 mg/dL. That’s a significant decline from the 18.3% who had high levels in 1999-2000.

Cholesterol levels in the U.S. have been declining over the past few decades. That’s mostly thanks to a greater national awareness of cholesterol’s role in contributing to heart disease and better drugs to lower cholesterol, such as statins and PCSK-9 inhibitors. Public health campaigns about healthy weight and the benefits of exercise also likely contributed to improving cholesterol levels.

There was also positive news about levels of HDL, or good cholesterol. Experts consider HDL levels greater than 40 mg/dL to be healthy and important in lowering the risk of heart disease. The latest survey showed that 18.4% of people had low HDL in 2015-16, compared to 22.2% in 2007-08. While the drop wasn’t statistically significant, it’s a trend in the right direction.

HDL levels can be affected by weight, exercise and smoking, among other things, and boosting HDL levels can keep total cholesterol levels down.

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The survey also revealed interesting trends that could help guide public health messages and programs in the future. More Hispanic adults, for example, had low HDL levels than African-Americans. That suggests that focusing on factors that increase HDL levels—such as maintaining a healthy weight, becoming more physically active and quitting smoking—may help to reduce heart disease risk among Hispanic Americans.

The data also suggest that many African-American adults have healthy HDL levels, and it may be worth studying what helps them maintain their desirable HDL cholesterol. While genetics may account for some of the healthy trend, behavioral factors may also contribute. Understanding and exploiting those factors to further reduce heart disease risk among this population, which tends to be more vulnerable to heart problems, may be valuable.