LDL subclass pattern B, reported to have a higher prevalence in hypertriglyceridemics (HTGs), is considered to be associated with an increased risk for coronary artery disease, and the small dense LDL characteristic of this pattern is susceptible to oxidative modification. Alcohol is considered one of the most frequent causes of increases in plasma triglyceride (TG) levels. We investigated the effects of alcohol withdrawal on LDL subclass distribution and oxidizability in drinkers with different plasma TG levels. Thirty-seven male subjects with relatively heavy alcohol-consumption habits were divided into four groups; normotriglyceridemic (NTG)/withdrawal (n = 11), NTG/control (n = 8), hypertriglyceridemic (HTG)/withdrawal (n = 10), and HTG/control (n = 8). Both withdrawal groups abstained form alcohol for 4 weeks, while the control subjects maintained their usual intake of alcohol. Peak LDL particle diameter (PPD) was smaller in the combined HTG groups than in the combined NTG groups before abstinence, although PPD increased significantly (P < .01) from 25.5 to 26.1 nm in the HTG/withdrawal group. Before abstinence, lag times preceding LDL oxidation in the combined HTG groups were shorter than in the combined NTG groups; after withdrawal, lag time was prolonged significantly (P < .01) from 49.9 to 57.3 minutes in the HTG-withdrawal group. No significant changes in PPD and lag time were observed in the other three groups. Significant correlations (P < .05) were observed between the change (delta) in the lag time and delta TG and between delta lag time and delta PPD. We conclude that in alcohol-induced HTG subjects, alcohol withdrawal has beneficial effects on the LDL profile by shifting the particle size from smaller to larger and decreasing its susceptibility to oxidation.