A study of over 1 million US veterans showed a U-shaped relationship between HDL and total mortality, with 50mg/dL as the level associated with the lowest mortality. [7, 2] In addition, an analysis of the Framingham study demonstrated that LDL and triglyceride levels modify HDL’s predictive value; CHD risk was found to be higher when low HDL was combined with high LDL and/or triglycerides as compared with the presence of low HDL levels alone. [8, 2] The relationship between HDL and CHD risk is also confounded by the presence of pro-atherogenic and inflammatory markers. 
Coronary heart disease: What you need to know The coronary arteries supply oxygen and blood to the heart. They can narrow, often because cholesterol accumulates on the arteries’ walls. This results in coronary heart disease, the most common type of heart disease in the U.S. Here, learn about risk factors, early warning signs, means of prevention, and treatments. Read now
Plasma HDL is a small, spherical, dense lipid-protein complex that is half lipid and half protein. The lipid component consists of phospholipids, free cholesterol, cholesteryl esters, and triglycerides. The protein component includes apo A-I (molecular weight, 28,000) and apo A-II (molecular weight, 17,000). Other minor, but important, proteins are apo E and apo C, including apo C-I, apo C-II, and apo C-III.
Too much cholesterol in the blood builds up on artery walls causing hardening of the arteries (atherosclerosis). The buildup of cholesterol narrows arteries, slowing or blocking the flow of oxygen-carrying blood to the heart, which can manifest as chest pain. If blood flow to the heart is cut off because of clogged arteries, the result is damage to the heart muscle – a heart attack.
As if we needed another excuse to grab a second scoop of guac at the tailgate? Avocados are the poster child for the heart-healthy diet due to their rich abundance of monounsaturated fat, high fiber, and potassium. Monounsaturated fats from avocados, in particular, have been connected to an increase of HDL cholesterol and decreases of total cholesterol, LDL particles, and triglycerides, as shown in an Archives of Medical Research study. These can even be substituted for heart-harmful hydrogenated oils in baked goods as the fruit yields the same creamy texture and mouthfeel. Avocado brownies anyone?!
The tendency toward high cholesterol appears to be genetic although diet also influences cholesterol levels. Other factors that can influence cholesterol levels include being overweight and being physically inactive. The older you get, the more likely your cholesterol levels are to rise. Before menopause, women tend to have lower cholesterol levels than men of the same age, but after menopause, women’s LDL levels often increase.
George T Griffing, MD is a member of the following medical societies: American Association for the Advancement of Science, International Society for Clinical Densitometry, Southern Society for Clinical Investigation, American College of Medical Practice Executives, American Association for Physician Leadership, American College of Physicians, American Diabetes Association, American Federation for Medical Research, American Heart Association, Central Society for Clinical and Translational Research, Endocrine Society
A study published in February 2016 in the journal PLoS One concluded as much. For nearly 11,000 adults, researchers found that low to moderate alcohol consumption (20 or fewer drinks a week for a man, 10 or fewer for a woman) led to higher levels of HDL cholesterol. It also helped get them to healthier overall cholesterol levels, decreasing triglycerides (blood fats in blood) and lowering LDL cholesterol.
If you smoke, it’s time to pack it in. According to the American Heart Association, smoking reduces your HDL cholesterol levels, while increasing your risk of heart disease, high blood pressure and diabetes. If you’re a smoker, you need to quit. Once you stop smoking, you can significantly improve your HDL cholesterol level very quickly and start protecting your heart. And if you’re a non-smoker, you need to avoid exposure to second-hand smoke to prevent your health from going up in smoke.