Our hearts appear to be a little healthier, by at least one measure anyway.
The Centers for Disease Control and Prevention (CDC) released a new report today that states the average levels of triglycerides among adults in the United States have been dropping over the past decade.
The report authors reached their conclusion by gathering data from the National Health and Nutrition Examination Survey between 2001 and 2012.
Of particular interest were triglycerides, fatty molecules formed by the liver as it digests fats and carbohydrates. These fatty molecules circulate in the bloodstream, where they may contribute to the build up of cholesterol plaques and the hardening of the arteries.
Heart disease is the leading cause of death among people in the United States.
“Many epidemiological studies have reported associations between triglyceride concentrations and the risk of coronary heart disease,” said Margaret D. Carroll, health statistician and lead author of the report, in an interview with Healthline.
The report found that the percentage of American adults age 20 or older who had triglyceride levels of 150 mg/dL or higher decreased from 33 percent in 2001 to 25 percent by 2012. Carroll noted that triglyceride levels remained steady between 1976 and 1991, and there were slight increases in levels between 1994 and 2002.
Heart health has been showing improvement in recent years, Carroll said. Obesity rates in the United States have leveled off since 2004 and the rates of heart disease deaths dropped steadily during the past decade.
Age, Sex, Race
The report found that in 2012, about 11 percent more men than women had elevated triglyceride levels between the ages of 20 and 60. Above the age of 60, the gender differences disappeared.
For men, triglyceride levels were highest (35 percent) in the 40 to 59 age group, while for women the highest rates were in the over-60 age group (31 percent).
These gender differences may have something to do with how the end of menopause and andropause affects women and men.
“Both genders are going to experience some hormonal shifts in the same age range divisions that we’re talking about,” explained Dr. Stanley G. Rockson, chief of consultative cardiology and professor of medicine at Stanford University, in an interview with Healthline. “Presumably it is hormonal in nature. The post-hormonal change in men creates a different environment than the post-hormonal change in women.”
The report also found some racial differences in the data.
Triglyceride levels dropped between 2001 and 2012 for both non-Hispanic white men and women. However, levels decreased for Mexican-American women but not men. For non-Hispanic black men and women the levels stayed the same.
However, non-Hispanic black men and women had the overall lowest levels of triglycerides by far — about half that of non-Hispanic white and Mexican-American men and women.
One possible explanation for this, Carroll suggests, may be that non-Hispanic black individuals tend to have higher levels of lipoprotein lipase, an enzyme that clears triglycerides from the bloodstream.
“If there’s a genetic basis by which that enzyme is more active in certain subgroups, you would expect the levels of triglyceride to be lower,” confirms Rockson.
What’s Causing the Change?
Carroll’s report points to some possible explanations for the drop in triglyceride levels. The past decade has seen a strong push to remove trans-fatty acids from processed foods. That has apparently translated into lower levels of trans-fatty acids in people’s bloodstreams.
Over the same time period, there has also been an increase in the percentage of adults taking medications that lower cholesterol levels. That may also affect triglyceride metabolism.
The decreases in triglyceride levels were greatest among overweight and obese adults, who are more likely to be prescribed such medications.
Inversely, the number of adults who smoke cigarettes has decreased. While Rockson isn’t sure smoking directly elevates triglyceride levels, he suggests that smoking cessation may also be accompanied by other health-oriented lifestyle shifts.
How Can I Lower My Triglyceride Levels?
Both Carroll and Rockson offer advice for reducing elevated triglyceride levels.
- Identify which processed foods in your diet contain trans fats and try to find healthier, trans-fat-free alternatives.
- Balance your calories. Don’t eat more than you’re going to burn with your activities in a given day.
- Increase the proportion of monounsaturated, polyunsaturated, and omega-3 fatty acids in your diet.
- Avoid foods with added sugars.
- Limit the amount of non-complex carbohydrates and alcohol you consume.
- Try to get to a healthy body weight.
- Get at least moderate amounts of exercise.
- Reduce or refrain from cigarette smoking.
- If necessary, consult with a physician about beginning appropriate medications.
“It’s important to underscore that we now know through almost a century’s worth of investigation that cholesterol and triglyceride are both very important elements for the generation and progression of the diseases that lead to heart attack and stroke,” Rockson concluded.