Adam Kieffer, MS
If you’ve visited your doctor for a check-up and had your blood cholesterol checked, chances are you were told about “good” and “bad” cholesterol. If your numbers weren’t the best, or you have a family history of heart disease, your doctor may have recommended that you decrease your “bad” cholesterol and increase your “good” cholesterol. Your “bad” cholesterol, or low-density lipoprotein (LDL) cholesterol delivers fat and cholesterol throughout your body, while your “good” cholesterol, or high-density lipoprotein (HDL) cholesterol returns cholesterol and fat to liver for processing. Long-term studies have shown that high LDL may increase your risk for heart disease, while HDL reduces your risk, hence the “bad” and “good” names for your blood cholesterol.
Unfortunately, naming them “good” and “bad” cholesterol might be too simple. Recently, scientists started to realize that your total amount of “good” and “bad” cholesterol may not be as important as how your cholesterol works. Functionality, or the ability of your blood cholesterol to do its job, might be more important than just the numbers; about 50% of people who have from heart attacks have “normal” LDL and HDL cholesterol. And when scientists increase HDL, or “good” cholesterol, in patients by using drugs, they fail to reduce the risk for heart disease. It may be that the HDL is dysfunction, or not working correctly. If the amount of cholesterol doesn’t matter, then what does? Interestingly, there appears to be a lot of variation on how your HDL cholesterol works. Scientists have only started to understand the complex (and sometimes confusing) nature of HDL.
A fat in your blood called sphingosine 1-phosphate (S1P) may be the key in helping us understand what makes our HDL cholesterol work properly. Studies have shown that S1P can ride on HDL and help it do its job: getting rid of extra fat and cholesterol in your body. It also seems to help HDL get larger which helps it stay in your blood longer, letting it do its job longer, and helping to take up more cargo. It has even been discovered that if more of your HDL has S1P, you are at a lower risk for heart disease.
What we do know is that exercise helps reduce the risk for heart disease, but did you know that exercise sometimes lowers HDL? Even so, the American College of Sports Medicine recommends exercise as a way to treat and prevent heart disease. Could exercise increase S1P content on HDL, making it work more effectively?
We don’t know the answers to these questions yet, but we just might, if we get funded.
1. Ansell BJ, Watson KE, Fogelman AM, Navab M, Fonarow GC. High-Density Lipoprotein Function: Recent Advances. Journal of the American College of Cardiology. 2005 Nov 15;46(10):1792–8.
2. Study Finds Lipid Mediator Associated with Good Cholesterol Promotes More Than Just Good Heart Health. Weill Cornell Newsroom. Weill Cornell Medical College. Available from: http://weill.cornell.edu/news/news/2015/06/study-finds-lipid-mediator-associated-with-good cholesterolpromotes-more-than-just-good-heart-healt.html
Note from the author: Opinions expressed are solely my own and do not express the views or opinions of the United States Army