The growth of civilization, particularly in the highly developed countries, has also changed trends in eating habits of their inhabitants. Unfortunately, the direction of these changes is not favourable for people’s health. They have become one of the main causes of morbidity and mortality due to obesity and overweight. This risk can be reduced by changes in people’s eating habits (diets, retrictions on consuming some sorts of products and their components). In the works of the U.S. Department of Health one can find the remarks emphasizing the importance of reducing the level of cholesterol, domestic salt, sugar and especially fat and after all hydrogenated fat. This latter can be substituted on a larger scale. A relatively long time ago it was noticed that maltodextrins with a low equivalent of glucose are able to substitute fat components. Therefore, for a few years scientists have been interested in oat and its products. It is connected with its chemical composition, particularly with soluble and insoluble components of cellulose and a high concentration of starch. The conducted enzymatic hydrolysis of starch under the proper conditions enables to obtain maltodextrins characterized by a proper glucose equivalent and also including some glucan fractions. This product known in the USA as „Oatrim” is used as a fat substitute in such groups of food as dressings, sauces, soups, mayonaize and margarine. It is estimated that the use of this substitute on American Market will reduce the costs of treatment of these diseases caused by obesity and a high level of cholesterol by 20 per cent.