Effects of smoking and smoking cessation on lipids and lipoproteins: Outcomes from a randomized clinical trial
American Heart Journal - Volume 161, Issue 1 (January 2011)
In this study, despite weight gain, smoking cessation improved HDL-C, total HDL, and large HDL particles, especially in women. Smoking cessation did not affect LDL or LDL size. Increases in HDL may mediate part of the reduced cardiovascular disease risk observed after smoking cessation.

Each year, smoking contributes to >443,000 smoking-related deaths in the United States and few millions in the rest of the world; and nearly 20% of all coronary heart disease deaths can be attributed to smoking. Although the strong relationship between smoking and cardiovascular disease (CVD) has been well-documented, the mechanisms by which smoking increases CVD risk appear to be multifactorial and incompletely understood. Clinical trials, suggest that cigarette smoking is associated with a more atherogenic lipid profile characterized by higher total cholesterol and triglycerides (TG) with lower levels of high-density lipoprotein cholesterol (HDL-C).

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