The development of new functional foods that contribute to the preservation and improvement of human health is one of the priorities in the food industry. In this regard, the production and sales of sugar confectionery products with low energy value and various enriching additives are gradually increasing, including those meant for diabetic therapeutic and dietary preventive nutrition. At the same time, the share of these products remains insignificant. The research prospective was to develop a technology for the production of marshmallow, which reduces the risk of obesity and type II diabetes. The study featured three samples of marshmallow: with granulated sugar, fructose, and inulin. The research determined the functional properties of the finished product. Three female volunteers (21, 32, and 45 years old) participated in the experiment. It was established that the replacement of granulated sugar with a natural sweetener, namely fructose and a mixture of fructose and inulin, led to a decrease in the body’s hyperglycemic response half an hour after consuming the analyzed sample, and resulted in a smooth sugar curve. Thus, natural additives and biologically active substances make sugar confectionery products functional, which is a priority for the development of the confectionery industry.