Epigenetic mechanisms affect cellular gene expression levels independently from DNA sequence. Epigenetic modifications can cause heritable phenotypic changes by the influence of environmental factors such as toxicants, nutrition and stress. Specific epigenetic marks that escape embryonic epigenetic reprogramming may have a role in obesity, cancer and cardiovascular disease susceptibility through subsequent generations. Recent studies point out that epigenetic may be related with complex diseases with unknown etiopathology. In this review, we summarized the effects of environmental factors on epigenome, epigenetic inheritance mechanisms across generations and related pathologies.