Successful weight maintenance preserves lower levels of oxidized LDL achieved by weight reduction in obese men

Objective: We studied the association between weight maintenance, oxidized low-density lipoprotein (ox-LDL) and other lipoproteins in obese men. Methods: A 2-month weight reduction phase (WRP) with a very-low-energy diet was followed by a 6-month weight maintenance period and an unsupervised 2-year follow-up. Ninety men entered and 68 (76%) completed the study. Subjects were analyzed as one group and after division into two subgroups: 20 most successful men in maintaining the lost weight (subgroup 1) and the remaining ( n = 48) men ( subgroup 2). Ox-LDL was measured by quantifying the amount of conjugated dienes in LDL particles. Results: The mean ( +/- s.d.) weight reduction at the end of the WRP ( n 68) was 14% ( confidence interval (CI) 12.9-14.7%, 14.5 +/- 74.2 kg, P < 0.001). Ox-LDL decreased by 22% (Cl 16.9-28.1, 12.3 +/- 15.4 mmol/l, P < 0.001). At the end of the 2-year follow-up, the regain in weight from the end of the WRP was 11% (Cl 9.0-12.4, 9.6 +/- 6.2 kg, P < 0.001). The regain in ox-LDL was 30% ( CI 18.7-41.2, 8.2 +/- 15.4 mu mol/l, P < 0.001). In subgroup 1 vs 2, the respective regains were 3% ( CI 0.9-4.2, 2.2 +/- 3.0 kg, P = 0.006) vs 14% ( CI 12.7-15.6, 12.9 +/- 4.0 kg, P < 0.001) regarding weight and 9% ( 2.0 +/- 6.9 mu mol/l, P = NS) vs 39% (Cl 23.7-53.9, 11.2 +/- 17.2 mu mol/l, P <= 0.001) in ox-LDL). Conclusion: The favorable changes seen in ox- LDL particles and serum lipids during weight reduction could be maintained by keeping the weight reduced, which may indicate decreased risk of atherosclerosis. But weight regain causes a resurge of ox- LDL.