The thesis deals with the field of nutriepigenetics, which covers the effect of food and its components on epigenetic modifications such as methylation of deoxyribonucleic acid, methylation and demethylation of histones, acetylation and deacetylation of histones, and expression of non-coding molecules of ribonucleic acid. Food and its components affect epigenetic modifications in various ways. They can be a source of substrate for acetylation and methylation. Food and its components can be also cofactors which are necessary for the activity of enzymes involved in these epigenetic modifications or in the production of the substrate. Additionally, they can affect the activity and expression of enzymes that are responsible for epigenetic modifications. All these impacts can be either direct or indirect. However not only specific components of food have impact on epigenetic modifications, but also reduction or increase of calorie intake.