The orthomolecular medicine emphasizes the usage of natural substances, found in healthy diets, such as vitamins, minerals, enzymes, amino acids, glyconutrients and fatty acids in the preventions and treatment of diseases. The orthomolecular medicine focus on the role of adequate nutrition to health. Nutrition comes first in diagnosis and treatment, whereas the medicine are used only for specific indications.

Orthomolecular medicine is defined as the provision of an optimal molecular constitution, especially the optimal concentration of substances that are normally present in the body, to treat diseases and maintain health.

Nutrients can be useful in the prevention and treatment of some diseases, but the conclusions of medical research point that the vast majority of statements about the treatment of diseases that defenders of orthomolecular medicine claim, are not supported by scientific evidence. The American Medical Association declared in 1997 that “many interventions on diet (as for vitamins, minerals or amino acids) recommended by practitioners of this alternative medicine are prudent and reasonable, but it described as "myth" the Idea that "the majority of diseases are caused by bad diets and can be prevented by nutritional interventions."