Methods: 150 healthy overweight volunteers will be divided into 2 groups; HCCD group and HCCD supplemented with the omega-3 fatty acids. Blood sample will be taken following an overnight 12 hour fast, before and after 8 weeks diet, for the following analysis: total cell count, plasma lipids, glucose and insulin, erythrocyte sedimentation rate, fibrinogen, white blood cell count, and CRP. Markers of leukocyte activation will be determined using FACS analysis. In addition, using ELISA, the following pro and anti inflammatory cytokines and markers for endothelial dysfunction will be analyzed: VCAM-1 and ICAM-1. Micro array analysis for genes transcription differences induced by HCCD will be performed in monocytes using Affymetrix chips.